libjpeg update

git-svn-id: http://svn.miranda-ng.org/main/trunk@5843 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c

1 files changed, 1597 insertions, 1597 deletions

diff --git a/plugins/AdvaImg/src/LibJPEG/transupp.c b/plugins/AdvaImg/src/LibJPEG/transupp.c
index 016f383d4f..e0af04cbd8 100644
--- a/plugins/AdvaImg/src/LibJPEG/transupp.c
+++ b/plugins/AdvaImg/src/LibJPEG/transupp.c
@@ -1,1597 +1,1597 @@
-/*
- * transupp.c
- *
- * Copyright (C) 1997-2011, Thomas G. Lane, Guido Vollbeding.
- * This file is part of the Independent JPEG Group's software.
- * For conditions of distribution and use, see the accompanying README file.
- *
- * This file contains image transformation routines and other utility code
- * used by the jpegtran sample application.  These are NOT part of the core
- * JPEG library.  But we keep these routines separate from jpegtran.c to
- * ease the task of maintaining jpegtran-like programs that have other user
- * interfaces.
- */
-
-/* Although this file really shouldn't have access to the library internals,
- * it's helpful to let it call jround_up() and jcopy_block_row().
- */
-#define JPEG_INTERNALS
-
-#include "jinclude.h"
-#include "jpeglib.h"
-#include "transupp.h"		/* My own external interface */
-#include <ctype.h>		/* to declare isdigit() */
-
-
-#if TRANSFORMS_SUPPORTED
-
-/*
- * Lossless image transformation routines.  These routines work on DCT
- * coefficient arrays and thus do not require any lossy decompression
- * or recompression of the image.
- * Thanks to Guido Vollbeding for the initial design and code of this feature,
- * and to Ben Jackson for introducing the cropping feature.
- *
- * Horizontal flipping is done in-place, using a single top-to-bottom
- * pass through the virtual source array.  It will thus be much the
- * fastest option for images larger than main memory.
- *
- * The other routines require a set of destination virtual arrays, so they
- * need twice as much memory as jpegtran normally does.  The destination
- * arrays are always written in normal scan order (top to bottom) because
- * the virtual array manager expects this.  The source arrays will be scanned
- * in the corresponding order, which means multiple passes through the source
- * arrays for most of the transforms.  That could result in much thrashing
- * if the image is larger than main memory.
- *
- * If cropping or trimming is involved, the destination arrays may be smaller
- * than the source arrays.  Note it is not possible to do horizontal flip
- * in-place when a nonzero Y crop offset is specified, since we'd have to move
- * data from one block row to another but the virtual array manager doesn't
- * guarantee we can touch more than one row at a time.  So in that case,
- * we have to use a separate destination array.
- *
- * Some notes about the operating environment of the individual transform
- * routines:
- * 1. Both the source and destination virtual arrays are allocated from the
- *    source JPEG object, and therefore should be manipulated by calling the
- *    source's memory manager.
- * 2. The destination's component count should be used.  It may be smaller
- *    than the source's when forcing to grayscale.
- * 3. Likewise the destination's sampling factors should be used.  When
- *    forcing to grayscale the destination's sampling factors will be all 1,
- *    and we may as well take that as the effective iMCU size.
- * 4. When "trim" is in effect, the destination's dimensions will be the
- *    trimmed values but the source's will be untrimmed.
- * 5. When "crop" is in effect, the destination's dimensions will be the
- *    cropped values but the source's will be uncropped.  Each transform
- *    routine is responsible for picking up source data starting at the
- *    correct X and Y offset for the crop region.  (The X and Y offsets
- *    passed to the transform routines are measured in iMCU blocks of the
- *    destination.)
- * 6. All the routines assume that the source and destination buffers are
- *    padded out to a full iMCU boundary.  This is true, although for the
- *    source buffer it is an undocumented property of jdcoefct.c.
- */
-
-
-LOCAL(void)
-do_crop (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
-	 JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
-	 jvirt_barray_ptr *src_coef_arrays,
-	 jvirt_barray_ptr *dst_coef_arrays)
-/* Crop.  This is only used when no rotate/flip is requested with the crop. */
-{
-  JDIMENSION dst_blk_y, x_crop_blocks, y_crop_blocks;
-  int ci, offset_y;
-  JBLOCKARRAY src_buffer, dst_buffer;
-  jpeg_component_info *compptr;
-
-  /* We simply have to copy the right amount of data (the destination's
-   * image size) starting at the given X and Y offsets in the source.
-   */
-  for (ci = 0; ci < dstinfo->num_components; ci++) {
-    compptr = dstinfo->comp_info + ci;
-    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
-    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
-    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
-	 dst_blk_y += compptr->v_samp_factor) {
-      dst_buffer = (*srcinfo->mem->access_virt_barray)
-	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
-	 (JDIMENSION) compptr->v_samp_factor, TRUE);
-      src_buffer = (*srcinfo->mem->access_virt_barray)
-	((j_common_ptr) srcinfo, src_coef_arrays[ci],
-	 dst_blk_y + y_crop_blocks,
-	 (JDIMENSION) compptr->v_samp_factor, FALSE);
-      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
-	jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,
-			dst_buffer[offset_y],
-			compptr->width_in_blocks);
-      }
-    }
-  }
-}
-
-
-LOCAL(void)
-do_flip_h_no_crop (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
-		   JDIMENSION x_crop_offset,
-		   jvirt_barray_ptr *src_coef_arrays)
-/* Horizontal flip; done in-place, so no separate dest array is required.
- * NB: this only works when y_crop_offset is zero.
- */
-{
-  JDIMENSION MCU_cols, comp_width, blk_x, blk_y, x_crop_blocks;
-  int ci, k, offset_y;
-  JBLOCKARRAY buffer;
-  JCOEFPTR ptr1, ptr2;
-  JCOEF temp1, temp2;
-  jpeg_component_info *compptr;
-
-  /* Horizontal mirroring of DCT blocks is accomplished by swapping
-   * pairs of blocks in-place.  Within a DCT block, we perform horizontal
-   * mirroring by changing the signs of odd-numbered columns.
-   * Partial iMCUs at the right edge are left untouched.
-   */
-  MCU_cols = srcinfo->output_width /
-    (dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);
-
-  for (ci = 0; ci < dstinfo->num_components; ci++) {
-    compptr = dstinfo->comp_info + ci;
-    comp_width = MCU_cols * compptr->h_samp_factor;
-    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
-    for (blk_y = 0; blk_y < compptr->height_in_blocks;
-	 blk_y += compptr->v_samp_factor) {
-      buffer = (*srcinfo->mem->access_virt_barray)
-	((j_common_ptr) srcinfo, src_coef_arrays[ci], blk_y,
-	 (JDIMENSION) compptr->v_samp_factor, TRUE);
-      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
-	/* Do the mirroring */
-	for (blk_x = 0; blk_x * 2 < comp_width; blk_x++) {
-	  ptr1 = buffer[offset_y][blk_x];
-	  ptr2 = buffer[offset_y][comp_width - blk_x - 1];
-	  /* this unrolled loop doesn't need to know which row it's on... */
-	  for (k = 0; k < DCTSIZE2; k += 2) {
-	    temp1 = *ptr1;	/* swap even column */
-	    temp2 = *ptr2;
-	    *ptr1++ = temp2;
-	    *ptr2++ = temp1;
-	    temp1 = *ptr1;	/* swap odd column with sign change */
-	    temp2 = *ptr2;
-	    *ptr1++ = -temp2;
-	    *ptr2++ = -temp1;
-	  }
-	}
-	if (x_crop_blocks > 0) {
-	  /* Now left-justify the portion of the data to be kept.
-	   * We can't use a single jcopy_block_row() call because that routine
-	   * depends on memcpy(), whose behavior is unspecified for overlapping
-	   * source and destination areas.  Sigh.
-	   */
-	  for (blk_x = 0; blk_x < compptr->width_in_blocks; blk_x++) {
-	    jcopy_block_row(buffer[offset_y] + blk_x + x_crop_blocks,
-			    buffer[offset_y] + blk_x,
-			    (JDIMENSION) 1);
-	  }
-	}
-      }
-    }
-  }
-}
-
-
-LOCAL(void)
-do_flip_h (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
-	   JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
-	   jvirt_barray_ptr *src_coef_arrays,
-	   jvirt_barray_ptr *dst_coef_arrays)
-/* Horizontal flip in general cropping case */
-{
-  JDIMENSION MCU_cols, comp_width, dst_blk_x, dst_blk_y;
-  JDIMENSION x_crop_blocks, y_crop_blocks;
-  int ci, k, offset_y;
-  JBLOCKARRAY src_buffer, dst_buffer;
-  JBLOCKROW src_row_ptr, dst_row_ptr;
-  JCOEFPTR src_ptr, dst_ptr;
-  jpeg_component_info *compptr;
-
-  /* Here we must output into a separate array because we can't touch
-   * different rows of a single virtual array simultaneously.  Otherwise,
-   * this is essentially the same as the routine above.
-   */
-  MCU_cols = srcinfo->output_width /
-    (dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);
-
-  for (ci = 0; ci < dstinfo->num_components; ci++) {
-    compptr = dstinfo->comp_info + ci;
-    comp_width = MCU_cols * compptr->h_samp_factor;
-    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
-    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
-    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
-	 dst_blk_y += compptr->v_samp_factor) {
-      dst_buffer = (*srcinfo->mem->access_virt_barray)
-	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
-	 (JDIMENSION) compptr->v_samp_factor, TRUE);
-      src_buffer = (*srcinfo->mem->access_virt_barray)
-	((j_common_ptr) srcinfo, src_coef_arrays[ci],
-	 dst_blk_y + y_crop_blocks,
-	 (JDIMENSION) compptr->v_samp_factor, FALSE);
-      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
-	dst_row_ptr = dst_buffer[offset_y];
-	src_row_ptr = src_buffer[offset_y];
-	for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
-	  if (x_crop_blocks + dst_blk_x < comp_width) {
-	    /* Do the mirrorable blocks */
-	    dst_ptr = dst_row_ptr[dst_blk_x];
-	    src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
-	    /* this unrolled loop doesn't need to know which row it's on... */
-	    for (k = 0; k < DCTSIZE2; k += 2) {
-	      *dst_ptr++ = *src_ptr++;	 /* copy even column */
-	      *dst_ptr++ = - *src_ptr++; /* copy odd column with sign change */
-	    }
-	  } else {
-	    /* Copy last partial block(s) verbatim */
-	    jcopy_block_row(src_row_ptr + dst_blk_x + x_crop_blocks,
-			    dst_row_ptr + dst_blk_x,
-			    (JDIMENSION) 1);
-	  }
-	}
-      }
-    }
-  }
-}
-
-
-LOCAL(void)
-do_flip_v (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
-	   JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
-	   jvirt_barray_ptr *src_coef_arrays,
-	   jvirt_barray_ptr *dst_coef_arrays)
-/* Vertical flip */
-{
-  JDIMENSION MCU_rows, comp_height, dst_blk_x, dst_blk_y;
-  JDIMENSION x_crop_blocks, y_crop_blocks;
-  int ci, i, j, offset_y;
-  JBLOCKARRAY src_buffer, dst_buffer;
-  JBLOCKROW src_row_ptr, dst_row_ptr;
-  JCOEFPTR src_ptr, dst_ptr;
-  jpeg_component_info *compptr;
-
-  /* We output into a separate array because we can't touch different
-   * rows of the source virtual array simultaneously.  Otherwise, this
-   * is a pretty straightforward analog of horizontal flip.
-   * Within a DCT block, vertical mirroring is done by changing the signs
-   * of odd-numbered rows.
-   * Partial iMCUs at the bottom edge are copied verbatim.
-   */
-  MCU_rows = srcinfo->output_height /
-    (dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);
-
-  for (ci = 0; ci < dstinfo->num_components; ci++) {
-    compptr = dstinfo->comp_info + ci;
-    comp_height = MCU_rows * compptr->v_samp_factor;
-    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
-    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
-    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
-	 dst_blk_y += compptr->v_samp_factor) {
-      dst_buffer = (*srcinfo->mem->access_virt_barray)
-	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
-	 (JDIMENSION) compptr->v_samp_factor, TRUE);
-      if (y_crop_blocks + dst_blk_y < comp_height) {
-	/* Row is within the mirrorable area. */
-	src_buffer = (*srcinfo->mem->access_virt_barray)
-	  ((j_common_ptr) srcinfo, src_coef_arrays[ci],
-	   comp_height - y_crop_blocks - dst_blk_y -
-	   (JDIMENSION) compptr->v_samp_factor,
-	   (JDIMENSION) compptr->v_samp_factor, FALSE);
-      } else {
-	/* Bottom-edge blocks will be copied verbatim. */
-	src_buffer = (*srcinfo->mem->access_virt_barray)
-	  ((j_common_ptr) srcinfo, src_coef_arrays[ci],
-	   dst_blk_y + y_crop_blocks,
-	   (JDIMENSION) compptr->v_samp_factor, FALSE);
-      }
-      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
-	if (y_crop_blocks + dst_blk_y < comp_height) {
-	  /* Row is within the mirrorable area. */
-	  dst_row_ptr = dst_buffer[offset_y];
-	  src_row_ptr = src_buffer[compptr->v_samp_factor - offset_y - 1];
-	  src_row_ptr += x_crop_blocks;
-	  for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
-	       dst_blk_x++) {
-	    dst_ptr = dst_row_ptr[dst_blk_x];
-	    src_ptr = src_row_ptr[dst_blk_x];
-	    for (i = 0; i < DCTSIZE; i += 2) {
-	      /* copy even row */
-	      for (j = 0; j < DCTSIZE; j++)
-		*dst_ptr++ = *src_ptr++;
-	      /* copy odd row with sign change */
-	      for (j = 0; j < DCTSIZE; j++)
-		*dst_ptr++ = - *src_ptr++;
-	    }
-	  }
-	} else {
-	  /* Just copy row verbatim. */
-	  jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,
-			  dst_buffer[offset_y],
-			  compptr->width_in_blocks);
-	}
-      }
-    }
-  }
-}
-
-
-LOCAL(void)
-do_transpose (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
-	      JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
-	      jvirt_barray_ptr *src_coef_arrays,
-	      jvirt_barray_ptr *dst_coef_arrays)
-/* Transpose source into destination */
-{
-  JDIMENSION dst_blk_x, dst_blk_y, x_crop_blocks, y_crop_blocks;
-  int ci, i, j, offset_x, offset_y;
-  JBLOCKARRAY src_buffer, dst_buffer;
-  JCOEFPTR src_ptr, dst_ptr;
-  jpeg_component_info *compptr;
-
-  /* Transposing pixels within a block just requires transposing the
-   * DCT coefficients.
-   * Partial iMCUs at the edges require no special treatment; we simply
-   * process all the available DCT blocks for every component.
-   */
-  for (ci = 0; ci < dstinfo->num_components; ci++) {
-    compptr = dstinfo->comp_info + ci;
-    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
-    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
-    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
-	 dst_blk_y += compptr->v_samp_factor) {
-      dst_buffer = (*srcinfo->mem->access_virt_barray)
-	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
-	 (JDIMENSION) compptr->v_samp_factor, TRUE);
-      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
-	for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
-	     dst_blk_x += compptr->h_samp_factor) {
-	  src_buffer = (*srcinfo->mem->access_virt_barray)
-	    ((j_common_ptr) srcinfo, src_coef_arrays[ci],
-	     dst_blk_x + x_crop_blocks,
-	     (JDIMENSION) compptr->h_samp_factor, FALSE);
-	  for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
-	    dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
-	    src_ptr = src_buffer[offset_x][dst_blk_y + offset_y + y_crop_blocks];
-	    for (i = 0; i < DCTSIZE; i++)
-	      for (j = 0; j < DCTSIZE; j++)
-		dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
-	  }
-	}
-      }
-    }
-  }
-}
-
-
-LOCAL(void)
-do_rot_90 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
-	   JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
-	   jvirt_barray_ptr *src_coef_arrays,
-	   jvirt_barray_ptr *dst_coef_arrays)
-/* 90 degree rotation is equivalent to
- *   1. Transposing the image;
- *   2. Horizontal mirroring.
- * These two steps are merged into a single processing routine.
- */
-{
-  JDIMENSION MCU_cols, comp_width, dst_blk_x, dst_blk_y;
-  JDIMENSION x_crop_blocks, y_crop_blocks;
-  int ci, i, j, offset_x, offset_y;
-  JBLOCKARRAY src_buffer, dst_buffer;
-  JCOEFPTR src_ptr, dst_ptr;
-  jpeg_component_info *compptr;
-
-  /* Because of the horizontal mirror step, we can't process partial iMCUs
-   * at the (output) right edge properly.  They just get transposed and
-   * not mirrored.
-   */
-  MCU_cols = srcinfo->output_height /
-    (dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);
-
-  for (ci = 0; ci < dstinfo->num_components; ci++) {
-    compptr = dstinfo->comp_info + ci;
-    comp_width = MCU_cols * compptr->h_samp_factor;
-    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
-    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
-    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
-	 dst_blk_y += compptr->v_samp_factor) {
-      dst_buffer = (*srcinfo->mem->access_virt_barray)
-	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
-	 (JDIMENSION) compptr->v_samp_factor, TRUE);
-      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
-	for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
-	     dst_blk_x += compptr->h_samp_factor) {
-	  if (x_crop_blocks + dst_blk_x < comp_width) {
-	    /* Block is within the mirrorable area. */
-	    src_buffer = (*srcinfo->mem->access_virt_barray)
-	      ((j_common_ptr) srcinfo, src_coef_arrays[ci],
-	       comp_width - x_crop_blocks - dst_blk_x -
-	       (JDIMENSION) compptr->h_samp_factor,
-	       (JDIMENSION) compptr->h_samp_factor, FALSE);
-	  } else {
-	    /* Edge blocks are transposed but not mirrored. */
-	    src_buffer = (*srcinfo->mem->access_virt_barray)
-	      ((j_common_ptr) srcinfo, src_coef_arrays[ci],
-	       dst_blk_x + x_crop_blocks,
-	       (JDIMENSION) compptr->h_samp_factor, FALSE);
-	  }
-	  for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
-	    dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
-	    if (x_crop_blocks + dst_blk_x < comp_width) {
-	      /* Block is within the mirrorable area. */
-	      src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]
-		[dst_blk_y + offset_y + y_crop_blocks];
-	      for (i = 0; i < DCTSIZE; i++) {
-		for (j = 0; j < DCTSIZE; j++)
-		  dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
-		i++;
-		for (j = 0; j < DCTSIZE; j++)
-		  dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
-	      }
-	    } else {
-	      /* Edge blocks are transposed but not mirrored. */
-	      src_ptr = src_buffer[offset_x]
-		[dst_blk_y + offset_y + y_crop_blocks];
-	      for (i = 0; i < DCTSIZE; i++)
-		for (j = 0; j < DCTSIZE; j++)
-		  dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
-	    }
-	  }
-	}
-      }
-    }
-  }
-}
-
-
-LOCAL(void)
-do_rot_270 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
-	    JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
-	    jvirt_barray_ptr *src_coef_arrays,
-	    jvirt_barray_ptr *dst_coef_arrays)
-/* 270 degree rotation is equivalent to
- *   1. Horizontal mirroring;
- *   2. Transposing the image.
- * These two steps are merged into a single processing routine.
- */
-{
-  JDIMENSION MCU_rows, comp_height, dst_blk_x, dst_blk_y;
-  JDIMENSION x_crop_blocks, y_crop_blocks;
-  int ci, i, j, offset_x, offset_y;
-  JBLOCKARRAY src_buffer, dst_buffer;
-  JCOEFPTR src_ptr, dst_ptr;
-  jpeg_component_info *compptr;
-
-  /* Because of the horizontal mirror step, we can't process partial iMCUs
-   * at the (output) bottom edge properly.  They just get transposed and
-   * not mirrored.
-   */
-  MCU_rows = srcinfo->output_width /
-    (dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);
-
-  for (ci = 0; ci < dstinfo->num_components; ci++) {
-    compptr = dstinfo->comp_info + ci;
-    comp_height = MCU_rows * compptr->v_samp_factor;
-    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
-    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
-    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
-	 dst_blk_y += compptr->v_samp_factor) {
-      dst_buffer = (*srcinfo->mem->access_virt_barray)
-	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
-	 (JDIMENSION) compptr->v_samp_factor, TRUE);
-      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
-	for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
-	     dst_blk_x += compptr->h_samp_factor) {
-	  src_buffer = (*srcinfo->mem->access_virt_barray)
-	    ((j_common_ptr) srcinfo, src_coef_arrays[ci],
-	     dst_blk_x + x_crop_blocks,
-	     (JDIMENSION) compptr->h_samp_factor, FALSE);
-	  for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
-	    dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
-	    if (y_crop_blocks + dst_blk_y < comp_height) {
-	      /* Block is within the mirrorable area. */
-	      src_ptr = src_buffer[offset_x]
-		[comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];
-	      for (i = 0; i < DCTSIZE; i++) {
-		for (j = 0; j < DCTSIZE; j++) {
-		  dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
-		  j++;
-		  dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
-		}
-	      }
-	    } else {
-	      /* Edge blocks are transposed but not mirrored. */
-	      src_ptr = src_buffer[offset_x]
-		[dst_blk_y + offset_y + y_crop_blocks];
-	      for (i = 0; i < DCTSIZE; i++)
-		for (j = 0; j < DCTSIZE; j++)
-		  dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
-	    }
-	  }
-	}
-      }
-    }
-  }
-}
-
-
-LOCAL(void)
-do_rot_180 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
-	    JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
-	    jvirt_barray_ptr *src_coef_arrays,
-	    jvirt_barray_ptr *dst_coef_arrays)
-/* 180 degree rotation is equivalent to
- *   1. Vertical mirroring;
- *   2. Horizontal mirroring.
- * These two steps are merged into a single processing routine.
- */
-{
-  JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height, dst_blk_x, dst_blk_y;
-  JDIMENSION x_crop_blocks, y_crop_blocks;
-  int ci, i, j, offset_y;
-  JBLOCKARRAY src_buffer, dst_buffer;
-  JBLOCKROW src_row_ptr, dst_row_ptr;
-  JCOEFPTR src_ptr, dst_ptr;
-  jpeg_component_info *compptr;
-
-  MCU_cols = srcinfo->output_width /
-    (dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);
-  MCU_rows = srcinfo->output_height /
-    (dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);
-
-  for (ci = 0; ci < dstinfo->num_components; ci++) {
-    compptr = dstinfo->comp_info + ci;
-    comp_width = MCU_cols * compptr->h_samp_factor;
-    comp_height = MCU_rows * compptr->v_samp_factor;
-    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
-    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
-    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
-	 dst_blk_y += compptr->v_samp_factor) {
-      dst_buffer = (*srcinfo->mem->access_virt_barray)
-	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
-	 (JDIMENSION) compptr->v_samp_factor, TRUE);
-      if (y_crop_blocks + dst_blk_y < comp_height) {
-	/* Row is within the vertically mirrorable area. */
-	src_buffer = (*srcinfo->mem->access_virt_barray)
-	  ((j_common_ptr) srcinfo, src_coef_arrays[ci],
-	   comp_height - y_crop_blocks - dst_blk_y -
-	   (JDIMENSION) compptr->v_samp_factor,
-	   (JDIMENSION) compptr->v_samp_factor, FALSE);
-      } else {
-	/* Bottom-edge rows are only mirrored horizontally. */
-	src_buffer = (*srcinfo->mem->access_virt_barray)
-	  ((j_common_ptr) srcinfo, src_coef_arrays[ci],
-	   dst_blk_y + y_crop_blocks,
-	   (JDIMENSION) compptr->v_samp_factor, FALSE);
-      }
-      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
-	dst_row_ptr = dst_buffer[offset_y];
-	if (y_crop_blocks + dst_blk_y < comp_height) {
-	  /* Row is within the mirrorable area. */
-	  src_row_ptr = src_buffer[compptr->v_samp_factor - offset_y - 1];
-	  for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
-	    dst_ptr = dst_row_ptr[dst_blk_x];
-	    if (x_crop_blocks + dst_blk_x < comp_width) {
-	      /* Process the blocks that can be mirrored both ways. */
-	      src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
-	      for (i = 0; i < DCTSIZE; i += 2) {
-		/* For even row, negate every odd column. */
-		for (j = 0; j < DCTSIZE; j += 2) {
-		  *dst_ptr++ = *src_ptr++;
-		  *dst_ptr++ = - *src_ptr++;
-		}
-		/* For odd row, negate every even column. */
-		for (j = 0; j < DCTSIZE; j += 2) {
-		  *dst_ptr++ = - *src_ptr++;
-		  *dst_ptr++ = *src_ptr++;
-		}
-	      }
-	    } else {
-	      /* Any remaining right-edge blocks are only mirrored vertically. */
-	      src_ptr = src_row_ptr[x_crop_blocks + dst_blk_x];
-	      for (i = 0; i < DCTSIZE; i += 2) {
-		for (j = 0; j < DCTSIZE; j++)
-		  *dst_ptr++ = *src_ptr++;
-		for (j = 0; j < DCTSIZE; j++)
-		  *dst_ptr++ = - *src_ptr++;
-	      }
-	    }
-	  }
-	} else {
-	  /* Remaining rows are just mirrored horizontally. */
-	  src_row_ptr = src_buffer[offset_y];
-	  for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
-	    if (x_crop_blocks + dst_blk_x < comp_width) {
-	      /* Process the blocks that can be mirrored. */
-	      dst_ptr = dst_row_ptr[dst_blk_x];
-	      src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
-	      for (i = 0; i < DCTSIZE2; i += 2) {
-		*dst_ptr++ = *src_ptr++;
-		*dst_ptr++ = - *src_ptr++;
-	      }
-	    } else {
-	      /* Any remaining right-edge blocks are only copied. */
-	      jcopy_block_row(src_row_ptr + dst_blk_x + x_crop_blocks,
-			      dst_row_ptr + dst_blk_x,
-			      (JDIMENSION) 1);
-	    }
-	  }
-	}
-      }
-    }
-  }
-}
-
-
-LOCAL(void)
-do_transverse (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
-	       JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
-	       jvirt_barray_ptr *src_coef_arrays,
-	       jvirt_barray_ptr *dst_coef_arrays)
-/* Transverse transpose is equivalent to
- *   1. 180 degree rotation;
- *   2. Transposition;
- * or
- *   1. Horizontal mirroring;
- *   2. Transposition;
- *   3. Horizontal mirroring.
- * These steps are merged into a single processing routine.
- */
-{
-  JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height, dst_blk_x, dst_blk_y;
-  JDIMENSION x_crop_blocks, y_crop_blocks;
-  int ci, i, j, offset_x, offset_y;
-  JBLOCKARRAY src_buffer, dst_buffer;
-  JCOEFPTR src_ptr, dst_ptr;
-  jpeg_component_info *compptr;
-
-  MCU_cols = srcinfo->output_height /
-    (dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);
-  MCU_rows = srcinfo->output_width /
-    (dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);
-
-  for (ci = 0; ci < dstinfo->num_components; ci++) {
-    compptr = dstinfo->comp_info + ci;
-    comp_width = MCU_cols * compptr->h_samp_factor;
-    comp_height = MCU_rows * compptr->v_samp_factor;
-    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
-    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
-    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
-	 dst_blk_y += compptr->v_samp_factor) {
-      dst_buffer = (*srcinfo->mem->access_virt_barray)
-	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
-	 (JDIMENSION) compptr->v_samp_factor, TRUE);
-      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
-	for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
-	     dst_blk_x += compptr->h_samp_factor) {
-	  if (x_crop_blocks + dst_blk_x < comp_width) {
-	    /* Block is within the mirrorable area. */
-	    src_buffer = (*srcinfo->mem->access_virt_barray)
-	      ((j_common_ptr) srcinfo, src_coef_arrays[ci],
-	       comp_width - x_crop_blocks - dst_blk_x -
-	       (JDIMENSION) compptr->h_samp_factor,
-	       (JDIMENSION) compptr->h_samp_factor, FALSE);
-	  } else {
-	    src_buffer = (*srcinfo->mem->access_virt_barray)
-	      ((j_common_ptr) srcinfo, src_coef_arrays[ci],
-	       dst_blk_x + x_crop_blocks,
-	       (JDIMENSION) compptr->h_samp_factor, FALSE);
-	  }
-	  for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
-	    dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
-	    if (y_crop_blocks + dst_blk_y < comp_height) {
-	      if (x_crop_blocks + dst_blk_x < comp_width) {
-		/* Block is within the mirrorable area. */
-		src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]
-		  [comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];
-		for (i = 0; i < DCTSIZE; i++) {
-		  for (j = 0; j < DCTSIZE; j++) {
-		    dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
-		    j++;
-		    dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
-		  }
-		  i++;
-		  for (j = 0; j < DCTSIZE; j++) {
-		    dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
-		    j++;
-		    dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
-		  }
-		}
-	      } else {
-		/* Right-edge blocks are mirrored in y only */
-		src_ptr = src_buffer[offset_x]
-		  [comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];
-		for (i = 0; i < DCTSIZE; i++) {
-		  for (j = 0; j < DCTSIZE; j++) {
-		    dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
-		    j++;
-		    dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
-		  }
-		}
-	      }
-	    } else {
-	      if (x_crop_blocks + dst_blk_x < comp_width) {
-		/* Bottom-edge blocks are mirrored in x only */
-		src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]
-		  [dst_blk_y + offset_y + y_crop_blocks];
-		for (i = 0; i < DCTSIZE; i++) {
-		  for (j = 0; j < DCTSIZE; j++)
-		    dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
-		  i++;
-		  for (j = 0; j < DCTSIZE; j++)
-		    dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
-		}
-	      } else {
-		/* At lower right corner, just transpose, no mirroring */
-		src_ptr = src_buffer[offset_x]
-		  [dst_blk_y + offset_y + y_crop_blocks];
-		for (i = 0; i < DCTSIZE; i++)
-		  for (j = 0; j < DCTSIZE; j++)
-		    dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
-	      }
-	    }
-	  }
-	}
-      }
-    }
-  }
-}
-
-
-/* Parse an unsigned integer: subroutine for jtransform_parse_crop_spec.
- * Returns TRUE if valid integer found, FALSE if not.
- * *strptr is advanced over the digit string, and *result is set to its value.
- */
-
-LOCAL(boolean)
-jt_read_integer (const char ** strptr, JDIMENSION * result)
-{
-  const char * ptr = *strptr;
-  JDIMENSION val = 0;
-
-  for (; isdigit(*ptr); ptr++) {
-    val = val * 10 + (JDIMENSION) (*ptr - '0');
-  }
-  *result = val;
-  if (ptr == *strptr)
-    return FALSE;		/* oops, no digits */
-  *strptr = ptr;
-  return TRUE;
-}
-
-
-/* Parse a crop specification (written in X11 geometry style).
- * The routine returns TRUE if the spec string is valid, FALSE if not.
- *
- * The crop spec string should have the format
- *	<width>[f]x<height>[f]{+-}<xoffset>{+-}<yoffset>
- * where width, height, xoffset, and yoffset are unsigned integers.
- * Each of the elements can be omitted to indicate a default value.
- * (A weakness of this style is that it is not possible to omit xoffset
- * while specifying yoffset, since they look alike.)
- *
- * This code is loosely based on XParseGeometry from the X11 distribution.
- */
-
-GLOBAL(boolean)
-jtransform_parse_crop_spec (jpeg_transform_info *info, const char *spec)
-{
-  info->crop = FALSE;
-  info->crop_width_set = JCROP_UNSET;
-  info->crop_height_set = JCROP_UNSET;
-  info->crop_xoffset_set = JCROP_UNSET;
-  info->crop_yoffset_set = JCROP_UNSET;
-
-  if (isdigit(*spec)) {
-    /* fetch width */
-    if (! jt_read_integer(&spec, &info->crop_width))
-      return FALSE;
-    if (*spec == 'f' || *spec == 'F') {
-      spec++;
-      info->crop_width_set = JCROP_FORCE;
-    } else
-      info->crop_width_set = JCROP_POS;
-  }
-  if (*spec == 'x' || *spec == 'X') {
-    /* fetch height */
-    spec++;
-    if (! jt_read_integer(&spec, &info->crop_height))
-      return FALSE;
-    if (*spec == 'f' || *spec == 'F') {
-      spec++;
-      info->crop_height_set = JCROP_FORCE;
-    } else
-      info->crop_height_set = JCROP_POS;
-  }
-  if (*spec == '+' || *spec == '-') {
-    /* fetch xoffset */
-    info->crop_xoffset_set = (*spec == '-') ? JCROP_NEG : JCROP_POS;
-    spec++;
-    if (! jt_read_integer(&spec, &info->crop_xoffset))
-      return FALSE;
-  }
-  if (*spec == '+' || *spec == '-') {
-    /* fetch yoffset */
-    info->crop_yoffset_set = (*spec == '-') ? JCROP_NEG : JCROP_POS;
-    spec++;
-    if (! jt_read_integer(&spec, &info->crop_yoffset))
-      return FALSE;
-  }
-  /* We had better have gotten to the end of the string. */
-  if (*spec != '\0')
-    return FALSE;
-  info->crop = TRUE;
-  return TRUE;
-}
-
-
-/* Trim off any partial iMCUs on the indicated destination edge */
-
-LOCAL(void)
-trim_right_edge (jpeg_transform_info *info, JDIMENSION full_width)
-{
-  JDIMENSION MCU_cols;
-
-  MCU_cols = info->output_width / info->iMCU_sample_width;
-  if (MCU_cols > 0 && info->x_crop_offset + MCU_cols ==
-      full_width / info->iMCU_sample_width)
-    info->output_width = MCU_cols * info->iMCU_sample_width;
-}
-
-LOCAL(void)
-trim_bottom_edge (jpeg_transform_info *info, JDIMENSION full_height)
-{
-  JDIMENSION MCU_rows;
-
-  MCU_rows = info->output_height / info->iMCU_sample_height;
-  if (MCU_rows > 0 && info->y_crop_offset + MCU_rows ==
-      full_height / info->iMCU_sample_height)
-    info->output_height = MCU_rows * info->iMCU_sample_height;
-}
-
-
-/* Request any required workspace.
- *
- * This routine figures out the size that the output image will be
- * (which implies that all the transform parameters must be set before
- * it is called).
- *
- * We allocate the workspace virtual arrays from the source decompression
- * object, so that all the arrays (both the original data and the workspace)
- * will be taken into account while making memory management decisions.
- * Hence, this routine must be called after jpeg_read_header (which reads
- * the image dimensions) and before jpeg_read_coefficients (which realizes
- * the source's virtual arrays).
- *
- * This function returns FALSE right away if -perfect is given
- * and transformation is not perfect.  Otherwise returns TRUE.
- */
-
-GLOBAL(boolean)
-jtransform_request_workspace (j_decompress_ptr srcinfo,
-			      jpeg_transform_info *info)
-{
-  jvirt_barray_ptr *coef_arrays;
-  boolean need_workspace, transpose_it;
-  jpeg_component_info *compptr;
-  JDIMENSION xoffset, yoffset;
-  JDIMENSION width_in_iMCUs, height_in_iMCUs;
-  JDIMENSION width_in_blocks, height_in_blocks;
-  int ci, h_samp_factor, v_samp_factor;
-
-  /* Determine number of components in output image */
-  if (info->force_grayscale &&
-      srcinfo->jpeg_color_space == JCS_YCbCr &&
-      srcinfo->num_components == 3)
-    /* We'll only process the first component */
-    info->num_components = 1;
-  else
-    /* Process all the components */
-    info->num_components = srcinfo->num_components;
-
-  /* Compute output image dimensions and related values. */
-  jpeg_core_output_dimensions(srcinfo);
-
-  /* Return right away if -perfect is given and transformation is not perfect.
-   */
-  if (info->perfect) {
-    if (info->num_components == 1) {
-      if (!jtransform_perfect_transform(srcinfo->output_width,
-	  srcinfo->output_height,
-	  srcinfo->min_DCT_h_scaled_size,
-	  srcinfo->min_DCT_v_scaled_size,
-	  info->transform))
-	return FALSE;
-    } else {
-      if (!jtransform_perfect_transform(srcinfo->output_width,
-	  srcinfo->output_height,
-	  srcinfo->max_h_samp_factor * srcinfo->min_DCT_h_scaled_size,
-	  srcinfo->max_v_samp_factor * srcinfo->min_DCT_v_scaled_size,
-	  info->transform))
-	return FALSE;
-    }
-  }
-
-  /* If there is only one output component, force the iMCU size to be 1;
-   * else use the source iMCU size.  (This allows us to do the right thing
-   * when reducing color to grayscale, and also provides a handy way of
-   * cleaning up "funny" grayscale images whose sampling factors are not 1x1.)
-   */
-  switch (info->transform) {
-  case JXFORM_TRANSPOSE:
-  case JXFORM_TRANSVERSE:
-  case JXFORM_ROT_90:
-  case JXFORM_ROT_270:
-    info->output_width = srcinfo->output_height;
-    info->output_height = srcinfo->output_width;
-    if (info->num_components == 1) {
-      info->iMCU_sample_width = srcinfo->min_DCT_v_scaled_size;
-      info->iMCU_sample_height = srcinfo->min_DCT_h_scaled_size;
-    } else {
-      info->iMCU_sample_width =
-	srcinfo->max_v_samp_factor * srcinfo->min_DCT_v_scaled_size;
-      info->iMCU_sample_height =
-	srcinfo->max_h_samp_factor * srcinfo->min_DCT_h_scaled_size;
-    }
-    break;
-  default:
-    info->output_width = srcinfo->output_width;
-    info->output_height = srcinfo->output_height;
-    if (info->num_components == 1) {
-      info->iMCU_sample_width = srcinfo->min_DCT_h_scaled_size;
-      info->iMCU_sample_height = srcinfo->min_DCT_v_scaled_size;
-    } else {
-      info->iMCU_sample_width =
-	srcinfo->max_h_samp_factor * srcinfo->min_DCT_h_scaled_size;
-      info->iMCU_sample_height =
-	srcinfo->max_v_samp_factor * srcinfo->min_DCT_v_scaled_size;
-    }
-    break;
-  }
-
-  /* If cropping has been requested, compute the crop area's position and
-   * dimensions, ensuring that its upper left corner falls at an iMCU boundary.
-   */
-  if (info->crop) {
-    /* Insert default values for unset crop parameters */
-    if (info->crop_xoffset_set == JCROP_UNSET)
-      info->crop_xoffset = 0;	/* default to +0 */
-    if (info->crop_yoffset_set == JCROP_UNSET)
-      info->crop_yoffset = 0;	/* default to +0 */
-    if (info->crop_xoffset >= info->output_width ||
-	info->crop_yoffset >= info->output_height)
-      ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
-    if (info->crop_width_set == JCROP_UNSET)
-      info->crop_width = info->output_width - info->crop_xoffset;
-    if (info->crop_height_set == JCROP_UNSET)
-      info->crop_height = info->output_height - info->crop_yoffset;
-    /* Ensure parameters are valid */
-    if (info->crop_width <= 0 || info->crop_width > info->output_width ||
-	info->crop_height <= 0 || info->crop_height > info->output_height ||
-	info->crop_xoffset > info->output_width - info->crop_width ||
-	info->crop_yoffset > info->output_height - info->crop_height)
-      ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
-    /* Convert negative crop offsets into regular offsets */
-    if (info->crop_xoffset_set == JCROP_NEG)
-      xoffset = info->output_width - info->crop_width - info->crop_xoffset;
-    else
-      xoffset = info->crop_xoffset;
-    if (info->crop_yoffset_set == JCROP_NEG)
-      yoffset = info->output_height - info->crop_height - info->crop_yoffset;
-    else
-      yoffset = info->crop_yoffset;
-    /* Now adjust so that upper left corner falls at an iMCU boundary */
-    if (info->crop_width_set == JCROP_FORCE)
-      info->output_width = info->crop_width;
-    else
-      info->output_width =
-        info->crop_width + (xoffset % info->iMCU_sample_width);
-    if (info->crop_height_set == JCROP_FORCE)
-      info->output_height = info->crop_height;
-    else
-      info->output_height =
-        info->crop_height + (yoffset % info->iMCU_sample_height);
-    /* Save x/y offsets measured in iMCUs */
-    info->x_crop_offset = xoffset / info->iMCU_sample_width;
-    info->y_crop_offset = yoffset / info->iMCU_sample_height;
-  } else {
-    info->x_crop_offset = 0;
-    info->y_crop_offset = 0;
-  }
-
-  /* Figure out whether we need workspace arrays,
-   * and if so whether they are transposed relative to the source.
-   */
-  need_workspace = FALSE;
-  transpose_it = FALSE;
-  switch (info->transform) {
-  case JXFORM_NONE:
-    if (info->x_crop_offset != 0 || info->y_crop_offset != 0)
-      need_workspace = TRUE;
-    /* No workspace needed if neither cropping nor transforming */
-    break;
-  case JXFORM_FLIP_H:
-    if (info->trim)
-      trim_right_edge(info, srcinfo->output_width);
-    if (info->y_crop_offset != 0)
-      need_workspace = TRUE;
-    /* do_flip_h_no_crop doesn't need a workspace array */
-    break;
-  case JXFORM_FLIP_V:
-    if (info->trim)
-      trim_bottom_edge(info, srcinfo->output_height);
-    /* Need workspace arrays having same dimensions as source image. */
-    need_workspace = TRUE;
-    break;
-  case JXFORM_TRANSPOSE:
-    /* transpose does NOT have to trim anything */
-    /* Need workspace arrays having transposed dimensions. */
-    need_workspace = TRUE;
-    transpose_it = TRUE;
-    break;
-  case JXFORM_TRANSVERSE:
-    if (info->trim) {
-      trim_right_edge(info, srcinfo->output_height);
-      trim_bottom_edge(info, srcinfo->output_width);
-    }
-    /* Need workspace arrays having transposed dimensions. */
-    need_workspace = TRUE;
-    transpose_it = TRUE;
-    break;
-  case JXFORM_ROT_90:
-    if (info->trim)
-      trim_right_edge(info, srcinfo->output_height);
-    /* Need workspace arrays having transposed dimensions. */
-    need_workspace = TRUE;
-    transpose_it = TRUE;
-    break;
-  case JXFORM_ROT_180:
-    if (info->trim) {
-      trim_right_edge(info, srcinfo->output_width);
-      trim_bottom_edge(info, srcinfo->output_height);
-    }
-    /* Need workspace arrays having same dimensions as source image. */
-    need_workspace = TRUE;
-    break;
-  case JXFORM_ROT_270:
-    if (info->trim)
-      trim_bottom_edge(info, srcinfo->output_width);
-    /* Need workspace arrays having transposed dimensions. */
-    need_workspace = TRUE;
-    transpose_it = TRUE;
-    break;
-  }
-
-  /* Allocate workspace if needed.
-   * Note that we allocate arrays padded out to the next iMCU boundary,
-   * so that transform routines need not worry about missing edge blocks.
-   */
-  if (need_workspace) {
-    coef_arrays = (jvirt_barray_ptr *)
-      (*srcinfo->mem->alloc_small) ((j_common_ptr) srcinfo, JPOOL_IMAGE,
-		SIZEOF(jvirt_barray_ptr) * info->num_components);
-    width_in_iMCUs = (JDIMENSION)
-      jdiv_round_up((long) info->output_width,
-		    (long) info->iMCU_sample_width);
-    height_in_iMCUs = (JDIMENSION)
-      jdiv_round_up((long) info->output_height,
-		    (long) info->iMCU_sample_height);
-    for (ci = 0; ci < info->num_components; ci++) {
-      compptr = srcinfo->comp_info + ci;
-      if (info->num_components == 1) {
-	/* we're going to force samp factors to 1x1 in this case */
-	h_samp_factor = v_samp_factor = 1;
-      } else if (transpose_it) {
-	h_samp_factor = compptr->v_samp_factor;
-	v_samp_factor = compptr->h_samp_factor;
-      } else {
-	h_samp_factor = compptr->h_samp_factor;
-	v_samp_factor = compptr->v_samp_factor;
-      }
-      width_in_blocks = width_in_iMCUs * h_samp_factor;
-      height_in_blocks = height_in_iMCUs * v_samp_factor;
-      coef_arrays[ci] = (*srcinfo->mem->request_virt_barray)
-	((j_common_ptr) srcinfo, JPOOL_IMAGE, FALSE,
-	 width_in_blocks, height_in_blocks, (JDIMENSION) v_samp_factor);
-    }
-    info->workspace_coef_arrays = coef_arrays;
-  } else
-    info->workspace_coef_arrays = NULL;
-
-  return TRUE;
-}
-
-
-/* Transpose destination image parameters */
-
-LOCAL(void)
-transpose_critical_parameters (j_compress_ptr dstinfo)
-{
-  int tblno, i, j, ci, itemp;
-  jpeg_component_info *compptr;
-  JQUANT_TBL *qtblptr;
-  JDIMENSION jtemp;
-  UINT16 qtemp;
-
-  /* Transpose image dimensions */
-  jtemp = dstinfo->image_width;
-  dstinfo->image_width = dstinfo->image_height;
-  dstinfo->image_height = jtemp;
-  itemp = dstinfo->min_DCT_h_scaled_size;
-  dstinfo->min_DCT_h_scaled_size = dstinfo->min_DCT_v_scaled_size;
-  dstinfo->min_DCT_v_scaled_size = itemp;
-
-  /* Transpose sampling factors */
-  for (ci = 0; ci < dstinfo->num_components; ci++) {
-    compptr = dstinfo->comp_info + ci;
-    itemp = compptr->h_samp_factor;
-    compptr->h_samp_factor = compptr->v_samp_factor;
-    compptr->v_samp_factor = itemp;
-  }
-
-  /* Transpose quantization tables */
-  for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) {
-    qtblptr = dstinfo->quant_tbl_ptrs[tblno];
-    if (qtblptr != NULL) {
-      for (i = 0; i < DCTSIZE; i++) {
-	for (j = 0; j < i; j++) {
-	  qtemp = qtblptr->quantval[i*DCTSIZE+j];
-	  qtblptr->quantval[i*DCTSIZE+j] = qtblptr->quantval[j*DCTSIZE+i];
-	  qtblptr->quantval[j*DCTSIZE+i] = qtemp;
-	}
-      }
-    }
-  }
-}
-
-
-/* Adjust Exif image parameters.
- *
- * We try to adjust the Tags ExifImageWidth and ExifImageHeight if possible.
- */
-
-LOCAL(void)
-adjust_exif_parameters (JOCTET FAR * data, unsigned int length,
-			JDIMENSION new_width, JDIMENSION new_height)
-{
-  boolean is_motorola; /* Flag for byte order */
-  unsigned int number_of_tags, tagnum;
-  unsigned int firstoffset, offset;
-  JDIMENSION new_value;
-
-  if (length < 12) return; /* Length of an IFD entry */
-
-  /* Discover byte order */
-  if (GETJOCTET(data[0]) == 0x49 && GETJOCTET(data[1]) == 0x49)
-    is_motorola = FALSE;
-  else if (GETJOCTET(data[0]) == 0x4D && GETJOCTET(data[1]) == 0x4D)
-    is_motorola = TRUE;
-  else
-    return;
-
-  /* Check Tag Mark */
-  if (is_motorola) {
-    if (GETJOCTET(data[2]) != 0) return;
-    if (GETJOCTET(data[3]) != 0x2A) return;
-  } else {
-    if (GETJOCTET(data[3]) != 0) return;
-    if (GETJOCTET(data[2]) != 0x2A) return;
-  }
-
-  /* Get first IFD offset (offset to IFD0) */
-  if (is_motorola) {
-    if (GETJOCTET(data[4]) != 0) return;
-    if (GETJOCTET(data[5]) != 0) return;
-    firstoffset = GETJOCTET(data[6]);
-    firstoffset <<= 8;
-    firstoffset += GETJOCTET(data[7]);
-  } else {
-    if (GETJOCTET(data[7]) != 0) return;
-    if (GETJOCTET(data[6]) != 0) return;
-    firstoffset = GETJOCTET(data[5]);
-    firstoffset <<= 8;
-    firstoffset += GETJOCTET(data[4]);
-  }
-  if (firstoffset > length - 2) return; /* check end of data segment */
-
-  /* Get the number of directory entries contained in this IFD */
-  if (is_motorola) {
-    number_of_tags = GETJOCTET(data[firstoffset]);
-    number_of_tags <<= 8;
-    number_of_tags += GETJOCTET(data[firstoffset+1]);
-  } else {
-    number_of_tags = GETJOCTET(data[firstoffset+1]);
-    number_of_tags <<= 8;
-    number_of_tags += GETJOCTET(data[firstoffset]);
-  }
-  if (number_of_tags == 0) return;
-  firstoffset += 2;
-
-  /* Search for ExifSubIFD offset Tag in IFD0 */
-  for (;;) {
-    if (firstoffset > length - 12) return; /* check end of data segment */
-    /* Get Tag number */
-    if (is_motorola) {
-      tagnum = GETJOCTET(data[firstoffset]);
-      tagnum <<= 8;
-      tagnum += GETJOCTET(data[firstoffset+1]);
-    } else {
-      tagnum = GETJOCTET(data[firstoffset+1]);
-      tagnum <<= 8;
-      tagnum += GETJOCTET(data[firstoffset]);
-    }
-    if (tagnum == 0x8769) break; /* found ExifSubIFD offset Tag */
-    if (--number_of_tags == 0) return;
-    firstoffset += 12;
-  }
-
-  /* Get the ExifSubIFD offset */
-  if (is_motorola) {
-    if (GETJOCTET(data[firstoffset+8]) != 0) return;
-    if (GETJOCTET(data[firstoffset+9]) != 0) return;
-    offset = GETJOCTET(data[firstoffset+10]);
-    offset <<= 8;
-    offset += GETJOCTET(data[firstoffset+11]);
-  } else {
-    if (GETJOCTET(data[firstoffset+11]) != 0) return;
-    if (GETJOCTET(data[firstoffset+10]) != 0) return;
-    offset = GETJOCTET(data[firstoffset+9]);
-    offset <<= 8;
-    offset += GETJOCTET(data[firstoffset+8]);
-  }
-  if (offset > length - 2) return; /* check end of data segment */
-
-  /* Get the number of directory entries contained in this SubIFD */
-  if (is_motorola) {
-    number_of_tags = GETJOCTET(data[offset]);
-    number_of_tags <<= 8;
-    number_of_tags += GETJOCTET(data[offset+1]);
-  } else {
-    number_of_tags = GETJOCTET(data[offset+1]);
-    number_of_tags <<= 8;
-    number_of_tags += GETJOCTET(data[offset]);
-  }
-  if (number_of_tags < 2) return;
-  offset += 2;
-
-  /* Search for ExifImageWidth and ExifImageHeight Tags in this SubIFD */
-  do {
-    if (offset > length - 12) return; /* check end of data segment */
-    /* Get Tag number */
-    if (is_motorola) {
-      tagnum = GETJOCTET(data[offset]);
-      tagnum <<= 8;
-      tagnum += GETJOCTET(data[offset+1]);
-    } else {
-      tagnum = GETJOCTET(data[offset+1]);
-      tagnum <<= 8;
-      tagnum += GETJOCTET(data[offset]);
-    }
-    if (tagnum == 0xA002 || tagnum == 0xA003) {
-      if (tagnum == 0xA002)
-	new_value = new_width; /* ExifImageWidth Tag */
-      else
-	new_value = new_height; /* ExifImageHeight Tag */
-      if (is_motorola) {
-	data[offset+2] = 0; /* Format = unsigned long (4 octets) */
-	data[offset+3] = 4;
-	data[offset+4] = 0; /* Number Of Components = 1 */
-	data[offset+5] = 0;
-	data[offset+6] = 0;
-	data[offset+7] = 1;
-	data[offset+8] = 0;
-	data[offset+9] = 0;
-	data[offset+10] = (JOCTET)((new_value >> 8) & 0xFF);
-	data[offset+11] = (JOCTET)(new_value & 0xFF);
-      } else {
-	data[offset+2] = 4; /* Format = unsigned long (4 octets) */
-	data[offset+3] = 0;
-	data[offset+4] = 1; /* Number Of Components = 1 */
-	data[offset+5] = 0;
-	data[offset+6] = 0;
-	data[offset+7] = 0;
-	data[offset+8] = (JOCTET)(new_value & 0xFF);
-	data[offset+9] = (JOCTET)((new_value >> 8) & 0xFF);
-	data[offset+10] = 0;
-	data[offset+11] = 0;
-      }
-    }
-    offset += 12;
-  } while (--number_of_tags);
-}
-
-
-/* Adjust output image parameters as needed.
- *
- * This must be called after jpeg_copy_critical_parameters()
- * and before jpeg_write_coefficients().
- *
- * The return value is the set of virtual coefficient arrays to be written
- * (either the ones allocated by jtransform_request_workspace, or the
- * original source data arrays).  The caller will need to pass this value
- * to jpeg_write_coefficients().
- */
-
-GLOBAL(jvirt_barray_ptr *)
-jtransform_adjust_parameters (j_decompress_ptr srcinfo,
-			      j_compress_ptr dstinfo,
-			      jvirt_barray_ptr *src_coef_arrays,
-			      jpeg_transform_info *info)
-{
-  /* If force-to-grayscale is requested, adjust destination parameters */
-  if (info->force_grayscale) {
-    /* First, ensure we have YCbCr or grayscale data, and that the source's
-     * Y channel is full resolution.  (No reasonable person would make Y
-     * be less than full resolution, so actually coping with that case
-     * isn't worth extra code space.  But we check it to avoid crashing.)
-     */
-    if (((dstinfo->jpeg_color_space == JCS_YCbCr &&
-	  dstinfo->num_components == 3) ||
-	 (dstinfo->jpeg_color_space == JCS_GRAYSCALE &&
-	  dstinfo->num_components == 1)) &&
-	srcinfo->comp_info[0].h_samp_factor == srcinfo->max_h_samp_factor &&
-	srcinfo->comp_info[0].v_samp_factor == srcinfo->max_v_samp_factor) {
-      /* We use jpeg_set_colorspace to make sure subsidiary settings get fixed
-       * properly.  Among other things, it sets the target h_samp_factor &
-       * v_samp_factor to 1, which typically won't match the source.
-       * We have to preserve the source's quantization table number, however.
-       */
-      int sv_quant_tbl_no = dstinfo->comp_info[0].quant_tbl_no;
-      jpeg_set_colorspace(dstinfo, JCS_GRAYSCALE);
-      dstinfo->comp_info[0].quant_tbl_no = sv_quant_tbl_no;
-    } else {
-      /* Sorry, can't do it */
-      ERREXIT(dstinfo, JERR_CONVERSION_NOTIMPL);
-    }
-  } else if (info->num_components == 1) {
-    /* For a single-component source, we force the destination sampling factors
-     * to 1x1, with or without force_grayscale.  This is useful because some
-     * decoders choke on grayscale images with other sampling factors.
-     */
-    dstinfo->comp_info[0].h_samp_factor = 1;
-    dstinfo->comp_info[0].v_samp_factor = 1;
-  }
-
-  /* Correct the destination's image dimensions as necessary
-   * for rotate/flip, resize, and crop operations.
-   */
-  dstinfo->jpeg_width = info->output_width;
-  dstinfo->jpeg_height = info->output_height;
-
-  /* Transpose destination image parameters */
-  switch (info->transform) {
-  case JXFORM_TRANSPOSE:
-  case JXFORM_TRANSVERSE:
-  case JXFORM_ROT_90:
-  case JXFORM_ROT_270:
-    transpose_critical_parameters(dstinfo);
-    break;
-  default:
-    break;
-  }
-
-  /* Adjust Exif properties */
-  if (srcinfo->marker_list != NULL &&
-      srcinfo->marker_list->marker == JPEG_APP0+1 &&
-      srcinfo->marker_list->data_length >= 6 &&
-      GETJOCTET(srcinfo->marker_list->data[0]) == 0x45 &&
-      GETJOCTET(srcinfo->marker_list->data[1]) == 0x78 &&
-      GETJOCTET(srcinfo->marker_list->data[2]) == 0x69 &&
-      GETJOCTET(srcinfo->marker_list->data[3]) == 0x66 &&
-      GETJOCTET(srcinfo->marker_list->data[4]) == 0 &&
-      GETJOCTET(srcinfo->marker_list->data[5]) == 0) {
-    /* Suppress output of JFIF marker */
-    dstinfo->write_JFIF_header = FALSE;
-    /* Adjust Exif image parameters */
-    if (dstinfo->jpeg_width != srcinfo->image_width ||
-	dstinfo->jpeg_height != srcinfo->image_height)
-      /* Align data segment to start of TIFF structure for parsing */
-      adjust_exif_parameters(srcinfo->marker_list->data + 6,
-	srcinfo->marker_list->data_length - 6,
-	dstinfo->jpeg_width, dstinfo->jpeg_height);
-  }
-
-  /* Return the appropriate output data set */
-  if (info->workspace_coef_arrays != NULL)
-    return info->workspace_coef_arrays;
-  return src_coef_arrays;
-}
-
-
-/* Execute the actual transformation, if any.
- *
- * This must be called *after* jpeg_write_coefficients, because it depends
- * on jpeg_write_coefficients to have computed subsidiary values such as
- * the per-component width and height fields in the destination object.
- *
- * Note that some transformations will modify the source data arrays!
- */
-
-GLOBAL(void)
-jtransform_execute_transform (j_decompress_ptr srcinfo,
-			      j_compress_ptr dstinfo,
-			      jvirt_barray_ptr *src_coef_arrays,
-			      jpeg_transform_info *info)
-{
-  jvirt_barray_ptr *dst_coef_arrays = info->workspace_coef_arrays;
-
-  /* Note: conditions tested here should match those in switch statement
-   * in jtransform_request_workspace()
-   */
-  switch (info->transform) {
-  case JXFORM_NONE:
-    if (info->x_crop_offset != 0 || info->y_crop_offset != 0)
-      do_crop(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
-	      src_coef_arrays, dst_coef_arrays);
-    break;
-  case JXFORM_FLIP_H:
-    if (info->y_crop_offset != 0)
-      do_flip_h(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
-		src_coef_arrays, dst_coef_arrays);
-    else
-      do_flip_h_no_crop(srcinfo, dstinfo, info->x_crop_offset,
-			src_coef_arrays);
-    break;
-  case JXFORM_FLIP_V:
-    do_flip_v(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
-	      src_coef_arrays, dst_coef_arrays);
-    break;
-  case JXFORM_TRANSPOSE:
-    do_transpose(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
-		 src_coef_arrays, dst_coef_arrays);
-    break;
-  case JXFORM_TRANSVERSE:
-    do_transverse(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
-		  src_coef_arrays, dst_coef_arrays);
-    break;
-  case JXFORM_ROT_90:
-    do_rot_90(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
-	      src_coef_arrays, dst_coef_arrays);
-    break;
-  case JXFORM_ROT_180:
-    do_rot_180(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
-	       src_coef_arrays, dst_coef_arrays);
-    break;
-  case JXFORM_ROT_270:
-    do_rot_270(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
-	       src_coef_arrays, dst_coef_arrays);
-    break;
-  }
-}
-
-/* jtransform_perfect_transform
- *
- * Determine whether lossless transformation is perfectly
- * possible for a specified image and transformation.
- *
- * Inputs:
- *   image_width, image_height: source image dimensions.
- *   MCU_width, MCU_height: pixel dimensions of MCU.
- *   transform: transformation identifier.
- * Parameter sources from initialized jpeg_struct
- * (after reading source header):
- *   image_width = cinfo.image_width
- *   image_height = cinfo.image_height
- *   MCU_width = cinfo.max_h_samp_factor * cinfo.block_size
- *   MCU_height = cinfo.max_v_samp_factor * cinfo.block_size
- * Result:
- *   TRUE = perfect transformation possible
- *   FALSE = perfect transformation not possible
- *           (may use custom action then)
- */
-
-GLOBAL(boolean)
-jtransform_perfect_transform(JDIMENSION image_width, JDIMENSION image_height,
-			     int MCU_width, int MCU_height,
-			     JXFORM_CODE transform)
-{
-  boolean result = TRUE; /* initialize TRUE */
-
-  switch (transform) {
-  case JXFORM_FLIP_H:
-  case JXFORM_ROT_270:
-    if (image_width % (JDIMENSION) MCU_width)
-      result = FALSE;
-    break;
-  case JXFORM_FLIP_V:
-  case JXFORM_ROT_90:
-    if (image_height % (JDIMENSION) MCU_height)
-      result = FALSE;
-    break;
-  case JXFORM_TRANSVERSE:
-  case JXFORM_ROT_180:
-    if (image_width % (JDIMENSION) MCU_width)
-      result = FALSE;
-    if (image_height % (JDIMENSION) MCU_height)
-      result = FALSE;
-    break;
-  default:
-    break;
-  }
-
-  return result;
-}
-
-#endif /* TRANSFORMS_SUPPORTED */
-
-
-/* Setup decompression object to save desired markers in memory.
- * This must be called before jpeg_read_header() to have the desired effect.
- */
-
-GLOBAL(void)
-jcopy_markers_setup (j_decompress_ptr srcinfo, JCOPY_OPTION option)
-{
-#ifdef SAVE_MARKERS_SUPPORTED
-  int m;
-
-  /* Save comments except under NONE option */
-  if (option != JCOPYOPT_NONE) {
-    jpeg_save_markers(srcinfo, JPEG_COM, 0xFFFF);
-  }
-  /* Save all types of APPn markers iff ALL option */
-  if (option == JCOPYOPT_ALL) {
-    for (m = 0; m < 16; m++)
-      jpeg_save_markers(srcinfo, JPEG_APP0 + m, 0xFFFF);
-  }
-#endif /* SAVE_MARKERS_SUPPORTED */
-}
-
-/* Copy markers saved in the given source object to the destination object.
- * This should be called just after jpeg_start_compress() or
- * jpeg_write_coefficients().
- * Note that those routines will have written the SOI, and also the
- * JFIF APP0 or Adobe APP14 markers if selected.
- */
-
-GLOBAL(void)
-jcopy_markers_execute (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
-		       JCOPY_OPTION option)
-{
-  jpeg_saved_marker_ptr marker;
-
-  /* In the current implementation, we don't actually need to examine the
-   * option flag here; we just copy everything that got saved.
-   * But to avoid confusion, we do not output JFIF and Adobe APP14 markers
-   * if the encoder library already wrote one.
-   */
-  for (marker = srcinfo->marker_list; marker != NULL; marker = marker->next) {
-    if (dstinfo->write_JFIF_header &&
-	marker->marker == JPEG_APP0 &&
-	marker->data_length >= 5 &&
-	GETJOCTET(marker->data[0]) == 0x4A &&
-	GETJOCTET(marker->data[1]) == 0x46 &&
-	GETJOCTET(marker->data[2]) == 0x49 &&
-	GETJOCTET(marker->data[3]) == 0x46 &&
-	GETJOCTET(marker->data[4]) == 0)
-      continue;			/* reject duplicate JFIF */
-    if (dstinfo->write_Adobe_marker &&
-	marker->marker == JPEG_APP0+14 &&
-	marker->data_length >= 5 &&
-	GETJOCTET(marker->data[0]) == 0x41 &&
-	GETJOCTET(marker->data[1]) == 0x64 &&
-	GETJOCTET(marker->data[2]) == 0x6F &&
-	GETJOCTET(marker->data[3]) == 0x62 &&
-	GETJOCTET(marker->data[4]) == 0x65)
-      continue;			/* reject duplicate Adobe */
-#ifdef NEED_FAR_POINTERS
-    /* We could use jpeg_write_marker if the data weren't FAR... */
-    {
-      unsigned int i;
-      jpeg_write_m_header(dstinfo, marker->marker, marker->data_length);
-      for (i = 0; i < marker->data_length; i++)
-	jpeg_write_m_byte(dstinfo, marker->data[i]);
-    }
-#else
-    jpeg_write_marker(dstinfo, marker->marker,
-		      marker->data, marker->data_length);
-#endif
-  }
-}
+/*

+ * transupp.c

+ *

+ * Copyright (C) 1997-2012, Thomas G. Lane, Guido Vollbeding.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains image transformation routines and other utility code

+ * used by the jpegtran sample application.  These are NOT part of the core

+ * JPEG library.  But we keep these routines separate from jpegtran.c to

+ * ease the task of maintaining jpegtran-like programs that have other user

+ * interfaces.

+ */

+

+/* Although this file really shouldn't have access to the library internals,

+ * it's helpful to let it call jround_up() and jcopy_block_row().

+ */

+#define JPEG_INTERNALS

+

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "transupp.h"		/* My own external interface */

+#include <ctype.h>		/* to declare isdigit() */

+

+

+#if TRANSFORMS_SUPPORTED

+

+/*

+ * Lossless image transformation routines.  These routines work on DCT

+ * coefficient arrays and thus do not require any lossy decompression

+ * or recompression of the image.

+ * Thanks to Guido Vollbeding for the initial design and code of this feature,

+ * and to Ben Jackson for introducing the cropping feature.

+ *

+ * Horizontal flipping is done in-place, using a single top-to-bottom

+ * pass through the virtual source array.  It will thus be much the

+ * fastest option for images larger than main memory.

+ *

+ * The other routines require a set of destination virtual arrays, so they

+ * need twice as much memory as jpegtran normally does.  The destination

+ * arrays are always written in normal scan order (top to bottom) because

+ * the virtual array manager expects this.  The source arrays will be scanned

+ * in the corresponding order, which means multiple passes through the source

+ * arrays for most of the transforms.  That could result in much thrashing

+ * if the image is larger than main memory.

+ *

+ * If cropping or trimming is involved, the destination arrays may be smaller

+ * than the source arrays.  Note it is not possible to do horizontal flip

+ * in-place when a nonzero Y crop offset is specified, since we'd have to move

+ * data from one block row to another but the virtual array manager doesn't

+ * guarantee we can touch more than one row at a time.  So in that case,

+ * we have to use a separate destination array.

+ *

+ * Some notes about the operating environment of the individual transform

+ * routines:

+ * 1. Both the source and destination virtual arrays are allocated from the

+ *    source JPEG object, and therefore should be manipulated by calling the

+ *    source's memory manager.

+ * 2. The destination's component count should be used.  It may be smaller

+ *    than the source's when forcing to grayscale.

+ * 3. Likewise the destination's sampling factors should be used.  When

+ *    forcing to grayscale the destination's sampling factors will be all 1,

+ *    and we may as well take that as the effective iMCU size.

+ * 4. When "trim" is in effect, the destination's dimensions will be the

+ *    trimmed values but the source's will be untrimmed.

+ * 5. When "crop" is in effect, the destination's dimensions will be the

+ *    cropped values but the source's will be uncropped.  Each transform

+ *    routine is responsible for picking up source data starting at the

+ *    correct X and Y offset for the crop region.  (The X and Y offsets

+ *    passed to the transform routines are measured in iMCU blocks of the

+ *    destination.)

+ * 6. All the routines assume that the source and destination buffers are

+ *    padded out to a full iMCU boundary.  This is true, although for the

+ *    source buffer it is an undocumented property of jdcoefct.c.

+ */

+

+

+LOCAL(void)

+do_crop (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,

+	 JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,

+	 jvirt_barray_ptr *src_coef_arrays,

+	 jvirt_barray_ptr *dst_coef_arrays)

+/* Crop.  This is only used when no rotate/flip is requested with the crop. */

+{

+  JDIMENSION dst_blk_y, x_crop_blocks, y_crop_blocks;

+  int ci, offset_y;

+  JBLOCKARRAY src_buffer, dst_buffer;

+  jpeg_component_info *compptr;

+

+  /* We simply have to copy the right amount of data (the destination's

+   * image size) starting at the given X and Y offsets in the source.

+   */

+  for (ci = 0; ci < dstinfo->num_components; ci++) {

+    compptr = dstinfo->comp_info + ci;

+    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;

+    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;

+    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;

+	 dst_blk_y += compptr->v_samp_factor) {

+      dst_buffer = (*srcinfo->mem->access_virt_barray)

+	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,

+	 (JDIMENSION) compptr->v_samp_factor, TRUE);

+      src_buffer = (*srcinfo->mem->access_virt_barray)

+	((j_common_ptr) srcinfo, src_coef_arrays[ci],

+	 dst_blk_y + y_crop_blocks,

+	 (JDIMENSION) compptr->v_samp_factor, FALSE);

+      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {

+	jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,

+			dst_buffer[offset_y],

+			compptr->width_in_blocks);

+      }

+    }

+  }

+}

+

+

+LOCAL(void)

+do_flip_h_no_crop (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,

+		   JDIMENSION x_crop_offset,

+		   jvirt_barray_ptr *src_coef_arrays)

+/* Horizontal flip; done in-place, so no separate dest array is required.

+ * NB: this only works when y_crop_offset is zero.

+ */

+{

+  JDIMENSION MCU_cols, comp_width, blk_x, blk_y, x_crop_blocks;

+  int ci, k, offset_y;

+  JBLOCKARRAY buffer;

+  JCOEFPTR ptr1, ptr2;

+  JCOEF temp1, temp2;

+  jpeg_component_info *compptr;

+

+  /* Horizontal mirroring of DCT blocks is accomplished by swapping

+   * pairs of blocks in-place.  Within a DCT block, we perform horizontal

+   * mirroring by changing the signs of odd-numbered columns.

+   * Partial iMCUs at the right edge are left untouched.

+   */

+  MCU_cols = srcinfo->output_width /

+    (dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);

+

+  for (ci = 0; ci < dstinfo->num_components; ci++) {

+    compptr = dstinfo->comp_info + ci;

+    comp_width = MCU_cols * compptr->h_samp_factor;

+    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;

+    for (blk_y = 0; blk_y < compptr->height_in_blocks;

+	 blk_y += compptr->v_samp_factor) {

+      buffer = (*srcinfo->mem->access_virt_barray)

+	((j_common_ptr) srcinfo, src_coef_arrays[ci], blk_y,

+	 (JDIMENSION) compptr->v_samp_factor, TRUE);

+      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {

+	/* Do the mirroring */

+	for (blk_x = 0; blk_x * 2 < comp_width; blk_x++) {

+	  ptr1 = buffer[offset_y][blk_x];

+	  ptr2 = buffer[offset_y][comp_width - blk_x - 1];

+	  /* this unrolled loop doesn't need to know which row it's on... */

+	  for (k = 0; k < DCTSIZE2; k += 2) {

+	    temp1 = *ptr1;	/* swap even column */

+	    temp2 = *ptr2;

+	    *ptr1++ = temp2;

+	    *ptr2++ = temp1;

+	    temp1 = *ptr1;	/* swap odd column with sign change */

+	    temp2 = *ptr2;

+	    *ptr1++ = -temp2;

+	    *ptr2++ = -temp1;

+	  }

+	}

+	if (x_crop_blocks > 0) {

+	  /* Now left-justify the portion of the data to be kept.

+	   * We can't use a single jcopy_block_row() call because that routine

+	   * depends on memcpy(), whose behavior is unspecified for overlapping

+	   * source and destination areas.  Sigh.

+	   */

+	  for (blk_x = 0; blk_x < compptr->width_in_blocks; blk_x++) {

+	    jcopy_block_row(buffer[offset_y] + blk_x + x_crop_blocks,

+			    buffer[offset_y] + blk_x,

+			    (JDIMENSION) 1);

+	  }

+	}

+      }

+    }

+  }

+}

+

+

+LOCAL(void)

+do_flip_h (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,

+	   JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,

+	   jvirt_barray_ptr *src_coef_arrays,

+	   jvirt_barray_ptr *dst_coef_arrays)

+/* Horizontal flip in general cropping case */

+{

+  JDIMENSION MCU_cols, comp_width, dst_blk_x, dst_blk_y;

+  JDIMENSION x_crop_blocks, y_crop_blocks;

+  int ci, k, offset_y;

+  JBLOCKARRAY src_buffer, dst_buffer;

+  JBLOCKROW src_row_ptr, dst_row_ptr;

+  JCOEFPTR src_ptr, dst_ptr;

+  jpeg_component_info *compptr;

+

+  /* Here we must output into a separate array because we can't touch

+   * different rows of a single virtual array simultaneously.  Otherwise,

+   * this is essentially the same as the routine above.

+   */

+  MCU_cols = srcinfo->output_width /

+    (dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);

+

+  for (ci = 0; ci < dstinfo->num_components; ci++) {

+    compptr = dstinfo->comp_info + ci;

+    comp_width = MCU_cols * compptr->h_samp_factor;

+    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;

+    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;

+    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;

+	 dst_blk_y += compptr->v_samp_factor) {

+      dst_buffer = (*srcinfo->mem->access_virt_barray)

+	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,

+	 (JDIMENSION) compptr->v_samp_factor, TRUE);

+      src_buffer = (*srcinfo->mem->access_virt_barray)

+	((j_common_ptr) srcinfo, src_coef_arrays[ci],

+	 dst_blk_y + y_crop_blocks,

+	 (JDIMENSION) compptr->v_samp_factor, FALSE);

+      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {

+	dst_row_ptr = dst_buffer[offset_y];

+	src_row_ptr = src_buffer[offset_y];

+	for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {

+	  if (x_crop_blocks + dst_blk_x < comp_width) {

+	    /* Do the mirrorable blocks */

+	    dst_ptr = dst_row_ptr[dst_blk_x];

+	    src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];

+	    /* this unrolled loop doesn't need to know which row it's on... */

+	    for (k = 0; k < DCTSIZE2; k += 2) {

+	      *dst_ptr++ = *src_ptr++;	 /* copy even column */

+	      *dst_ptr++ = - *src_ptr++; /* copy odd column with sign change */

+	    }

+	  } else {

+	    /* Copy last partial block(s) verbatim */

+	    jcopy_block_row(src_row_ptr + dst_blk_x + x_crop_blocks,

+			    dst_row_ptr + dst_blk_x,

+			    (JDIMENSION) 1);

+	  }

+	}

+      }

+    }

+  }

+}

+

+

+LOCAL(void)

+do_flip_v (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,

+	   JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,

+	   jvirt_barray_ptr *src_coef_arrays,

+	   jvirt_barray_ptr *dst_coef_arrays)

+/* Vertical flip */

+{

+  JDIMENSION MCU_rows, comp_height, dst_blk_x, dst_blk_y;

+  JDIMENSION x_crop_blocks, y_crop_blocks;

+  int ci, i, j, offset_y;

+  JBLOCKARRAY src_buffer, dst_buffer;

+  JBLOCKROW src_row_ptr, dst_row_ptr;

+  JCOEFPTR src_ptr, dst_ptr;

+  jpeg_component_info *compptr;

+

+  /* We output into a separate array because we can't touch different

+   * rows of the source virtual array simultaneously.  Otherwise, this

+   * is a pretty straightforward analog of horizontal flip.

+   * Within a DCT block, vertical mirroring is done by changing the signs

+   * of odd-numbered rows.

+   * Partial iMCUs at the bottom edge are copied verbatim.

+   */

+  MCU_rows = srcinfo->output_height /

+    (dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);

+

+  for (ci = 0; ci < dstinfo->num_components; ci++) {

+    compptr = dstinfo->comp_info + ci;

+    comp_height = MCU_rows * compptr->v_samp_factor;

+    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;

+    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;

+    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;

+	 dst_blk_y += compptr->v_samp_factor) {

+      dst_buffer = (*srcinfo->mem->access_virt_barray)

+	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,

+	 (JDIMENSION) compptr->v_samp_factor, TRUE);

+      if (y_crop_blocks + dst_blk_y < comp_height) {

+	/* Row is within the mirrorable area. */

+	src_buffer = (*srcinfo->mem->access_virt_barray)

+	  ((j_common_ptr) srcinfo, src_coef_arrays[ci],

+	   comp_height - y_crop_blocks - dst_blk_y -

+	   (JDIMENSION) compptr->v_samp_factor,

+	   (JDIMENSION) compptr->v_samp_factor, FALSE);

+      } else {

+	/* Bottom-edge blocks will be copied verbatim. */

+	src_buffer = (*srcinfo->mem->access_virt_barray)

+	  ((j_common_ptr) srcinfo, src_coef_arrays[ci],

+	   dst_blk_y + y_crop_blocks,

+	   (JDIMENSION) compptr->v_samp_factor, FALSE);

+      }

+      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {

+	if (y_crop_blocks + dst_blk_y < comp_height) {

+	  /* Row is within the mirrorable area. */

+	  dst_row_ptr = dst_buffer[offset_y];

+	  src_row_ptr = src_buffer[compptr->v_samp_factor - offset_y - 1];

+	  src_row_ptr += x_crop_blocks;

+	  for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;

+	       dst_blk_x++) {

+	    dst_ptr = dst_row_ptr[dst_blk_x];

+	    src_ptr = src_row_ptr[dst_blk_x];

+	    for (i = 0; i < DCTSIZE; i += 2) {

+	      /* copy even row */

+	      for (j = 0; j < DCTSIZE; j++)

+		*dst_ptr++ = *src_ptr++;

+	      /* copy odd row with sign change */

+	      for (j = 0; j < DCTSIZE; j++)

+		*dst_ptr++ = - *src_ptr++;

+	    }

+	  }

+	} else {

+	  /* Just copy row verbatim. */

+	  jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,

+			  dst_buffer[offset_y],

+			  compptr->width_in_blocks);

+	}

+      }

+    }

+  }

+}

+

+

+LOCAL(void)

+do_transpose (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,

+	      JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,

+	      jvirt_barray_ptr *src_coef_arrays,

+	      jvirt_barray_ptr *dst_coef_arrays)

+/* Transpose source into destination */

+{

+  JDIMENSION dst_blk_x, dst_blk_y, x_crop_blocks, y_crop_blocks;

+  int ci, i, j, offset_x, offset_y;

+  JBLOCKARRAY src_buffer, dst_buffer;

+  JCOEFPTR src_ptr, dst_ptr;

+  jpeg_component_info *compptr;

+

+  /* Transposing pixels within a block just requires transposing the

+   * DCT coefficients.

+   * Partial iMCUs at the edges require no special treatment; we simply

+   * process all the available DCT blocks for every component.

+   */

+  for (ci = 0; ci < dstinfo->num_components; ci++) {

+    compptr = dstinfo->comp_info + ci;

+    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;

+    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;

+    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;

+	 dst_blk_y += compptr->v_samp_factor) {

+      dst_buffer = (*srcinfo->mem->access_virt_barray)

+	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,

+	 (JDIMENSION) compptr->v_samp_factor, TRUE);

+      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {

+	for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;

+	     dst_blk_x += compptr->h_samp_factor) {

+	  src_buffer = (*srcinfo->mem->access_virt_barray)

+	    ((j_common_ptr) srcinfo, src_coef_arrays[ci],

+	     dst_blk_x + x_crop_blocks,

+	     (JDIMENSION) compptr->h_samp_factor, FALSE);

+	  for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {

+	    dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];

+	    src_ptr = src_buffer[offset_x][dst_blk_y + offset_y + y_crop_blocks];

+	    for (i = 0; i < DCTSIZE; i++)

+	      for (j = 0; j < DCTSIZE; j++)

+		dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];

+	  }

+	}

+      }

+    }

+  }

+}

+

+

+LOCAL(void)

+do_rot_90 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,

+	   JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,

+	   jvirt_barray_ptr *src_coef_arrays,

+	   jvirt_barray_ptr *dst_coef_arrays)

+/* 90 degree rotation is equivalent to

+ *   1. Transposing the image;

+ *   2. Horizontal mirroring.

+ * These two steps are merged into a single processing routine.

+ */

+{

+  JDIMENSION MCU_cols, comp_width, dst_blk_x, dst_blk_y;

+  JDIMENSION x_crop_blocks, y_crop_blocks;

+  int ci, i, j, offset_x, offset_y;

+  JBLOCKARRAY src_buffer, dst_buffer;

+  JCOEFPTR src_ptr, dst_ptr;

+  jpeg_component_info *compptr;

+

+  /* Because of the horizontal mirror step, we can't process partial iMCUs

+   * at the (output) right edge properly.  They just get transposed and

+   * not mirrored.

+   */

+  MCU_cols = srcinfo->output_height /

+    (dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);

+

+  for (ci = 0; ci < dstinfo->num_components; ci++) {

+    compptr = dstinfo->comp_info + ci;

+    comp_width = MCU_cols * compptr->h_samp_factor;

+    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;

+    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;

+    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;

+	 dst_blk_y += compptr->v_samp_factor) {

+      dst_buffer = (*srcinfo->mem->access_virt_barray)

+	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,

+	 (JDIMENSION) compptr->v_samp_factor, TRUE);

+      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {

+	for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;

+	     dst_blk_x += compptr->h_samp_factor) {

+	  if (x_crop_blocks + dst_blk_x < comp_width) {

+	    /* Block is within the mirrorable area. */

+	    src_buffer = (*srcinfo->mem->access_virt_barray)

+	      ((j_common_ptr) srcinfo, src_coef_arrays[ci],

+	       comp_width - x_crop_blocks - dst_blk_x -

+	       (JDIMENSION) compptr->h_samp_factor,

+	       (JDIMENSION) compptr->h_samp_factor, FALSE);

+	  } else {

+	    /* Edge blocks are transposed but not mirrored. */

+	    src_buffer = (*srcinfo->mem->access_virt_barray)

+	      ((j_common_ptr) srcinfo, src_coef_arrays[ci],

+	       dst_blk_x + x_crop_blocks,

+	       (JDIMENSION) compptr->h_samp_factor, FALSE);

+	  }

+	  for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {

+	    dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];

+	    if (x_crop_blocks + dst_blk_x < comp_width) {

+	      /* Block is within the mirrorable area. */

+	      src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]

+		[dst_blk_y + offset_y + y_crop_blocks];

+	      for (i = 0; i < DCTSIZE; i++) {

+		for (j = 0; j < DCTSIZE; j++)

+		  dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];

+		i++;

+		for (j = 0; j < DCTSIZE; j++)

+		  dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];

+	      }

+	    } else {

+	      /* Edge blocks are transposed but not mirrored. */

+	      src_ptr = src_buffer[offset_x]

+		[dst_blk_y + offset_y + y_crop_blocks];

+	      for (i = 0; i < DCTSIZE; i++)

+		for (j = 0; j < DCTSIZE; j++)

+		  dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];

+	    }

+	  }

+	}

+      }

+    }

+  }

+}

+

+

+LOCAL(void)

+do_rot_270 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,

+	    JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,

+	    jvirt_barray_ptr *src_coef_arrays,

+	    jvirt_barray_ptr *dst_coef_arrays)

+/* 270 degree rotation is equivalent to

+ *   1. Horizontal mirroring;

+ *   2. Transposing the image.

+ * These two steps are merged into a single processing routine.

+ */

+{

+  JDIMENSION MCU_rows, comp_height, dst_blk_x, dst_blk_y;

+  JDIMENSION x_crop_blocks, y_crop_blocks;

+  int ci, i, j, offset_x, offset_y;

+  JBLOCKARRAY src_buffer, dst_buffer;

+  JCOEFPTR src_ptr, dst_ptr;

+  jpeg_component_info *compptr;

+

+  /* Because of the horizontal mirror step, we can't process partial iMCUs

+   * at the (output) bottom edge properly.  They just get transposed and

+   * not mirrored.

+   */

+  MCU_rows = srcinfo->output_width /

+    (dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);

+

+  for (ci = 0; ci < dstinfo->num_components; ci++) {

+    compptr = dstinfo->comp_info + ci;

+    comp_height = MCU_rows * compptr->v_samp_factor;

+    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;

+    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;

+    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;

+	 dst_blk_y += compptr->v_samp_factor) {

+      dst_buffer = (*srcinfo->mem->access_virt_barray)

+	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,

+	 (JDIMENSION) compptr->v_samp_factor, TRUE);

+      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {

+	for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;

+	     dst_blk_x += compptr->h_samp_factor) {

+	  src_buffer = (*srcinfo->mem->access_virt_barray)

+	    ((j_common_ptr) srcinfo, src_coef_arrays[ci],

+	     dst_blk_x + x_crop_blocks,

+	     (JDIMENSION) compptr->h_samp_factor, FALSE);

+	  for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {

+	    dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];

+	    if (y_crop_blocks + dst_blk_y < comp_height) {

+	      /* Block is within the mirrorable area. */

+	      src_ptr = src_buffer[offset_x]

+		[comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];

+	      for (i = 0; i < DCTSIZE; i++) {

+		for (j = 0; j < DCTSIZE; j++) {

+		  dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];

+		  j++;

+		  dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];

+		}

+	      }

+	    } else {

+	      /* Edge blocks are transposed but not mirrored. */

+	      src_ptr = src_buffer[offset_x]

+		[dst_blk_y + offset_y + y_crop_blocks];

+	      for (i = 0; i < DCTSIZE; i++)

+		for (j = 0; j < DCTSIZE; j++)

+		  dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];

+	    }

+	  }

+	}

+      }

+    }

+  }

+}

+

+

+LOCAL(void)

+do_rot_180 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,

+	    JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,

+	    jvirt_barray_ptr *src_coef_arrays,

+	    jvirt_barray_ptr *dst_coef_arrays)

+/* 180 degree rotation is equivalent to

+ *   1. Vertical mirroring;

+ *   2. Horizontal mirroring.

+ * These two steps are merged into a single processing routine.

+ */

+{

+  JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height, dst_blk_x, dst_blk_y;

+  JDIMENSION x_crop_blocks, y_crop_blocks;

+  int ci, i, j, offset_y;

+  JBLOCKARRAY src_buffer, dst_buffer;

+  JBLOCKROW src_row_ptr, dst_row_ptr;

+  JCOEFPTR src_ptr, dst_ptr;

+  jpeg_component_info *compptr;

+

+  MCU_cols = srcinfo->output_width /

+    (dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);

+  MCU_rows = srcinfo->output_height /

+    (dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);

+

+  for (ci = 0; ci < dstinfo->num_components; ci++) {

+    compptr = dstinfo->comp_info + ci;

+    comp_width = MCU_cols * compptr->h_samp_factor;

+    comp_height = MCU_rows * compptr->v_samp_factor;

+    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;

+    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;

+    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;

+	 dst_blk_y += compptr->v_samp_factor) {

+      dst_buffer = (*srcinfo->mem->access_virt_barray)

+	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,

+	 (JDIMENSION) compptr->v_samp_factor, TRUE);

+      if (y_crop_blocks + dst_blk_y < comp_height) {

+	/* Row is within the vertically mirrorable area. */

+	src_buffer = (*srcinfo->mem->access_virt_barray)

+	  ((j_common_ptr) srcinfo, src_coef_arrays[ci],

+	   comp_height - y_crop_blocks - dst_blk_y -

+	   (JDIMENSION) compptr->v_samp_factor,

+	   (JDIMENSION) compptr->v_samp_factor, FALSE);

+      } else {

+	/* Bottom-edge rows are only mirrored horizontally. */

+	src_buffer = (*srcinfo->mem->access_virt_barray)

+	  ((j_common_ptr) srcinfo, src_coef_arrays[ci],

+	   dst_blk_y + y_crop_blocks,

+	   (JDIMENSION) compptr->v_samp_factor, FALSE);

+      }

+      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {

+	dst_row_ptr = dst_buffer[offset_y];

+	if (y_crop_blocks + dst_blk_y < comp_height) {

+	  /* Row is within the mirrorable area. */

+	  src_row_ptr = src_buffer[compptr->v_samp_factor - offset_y - 1];

+	  for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {

+	    dst_ptr = dst_row_ptr[dst_blk_x];

+	    if (x_crop_blocks + dst_blk_x < comp_width) {

+	      /* Process the blocks that can be mirrored both ways. */

+	      src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];

+	      for (i = 0; i < DCTSIZE; i += 2) {

+		/* For even row, negate every odd column. */

+		for (j = 0; j < DCTSIZE; j += 2) {

+		  *dst_ptr++ = *src_ptr++;

+		  *dst_ptr++ = - *src_ptr++;

+		}

+		/* For odd row, negate every even column. */

+		for (j = 0; j < DCTSIZE; j += 2) {

+		  *dst_ptr++ = - *src_ptr++;

+		  *dst_ptr++ = *src_ptr++;

+		}

+	      }

+	    } else {

+	      /* Any remaining right-edge blocks are only mirrored vertically. */

+	      src_ptr = src_row_ptr[x_crop_blocks + dst_blk_x];

+	      for (i = 0; i < DCTSIZE; i += 2) {

+		for (j = 0; j < DCTSIZE; j++)

+		  *dst_ptr++ = *src_ptr++;

+		for (j = 0; j < DCTSIZE; j++)

+		  *dst_ptr++ = - *src_ptr++;

+	      }

+	    }

+	  }

+	} else {

+	  /* Remaining rows are just mirrored horizontally. */

+	  src_row_ptr = src_buffer[offset_y];

+	  for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {

+	    if (x_crop_blocks + dst_blk_x < comp_width) {

+	      /* Process the blocks that can be mirrored. */

+	      dst_ptr = dst_row_ptr[dst_blk_x];

+	      src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];

+	      for (i = 0; i < DCTSIZE2; i += 2) {

+		*dst_ptr++ = *src_ptr++;

+		*dst_ptr++ = - *src_ptr++;

+	      }

+	    } else {

+	      /* Any remaining right-edge blocks are only copied. */

+	      jcopy_block_row(src_row_ptr + dst_blk_x + x_crop_blocks,

+			      dst_row_ptr + dst_blk_x,

+			      (JDIMENSION) 1);

+	    }

+	  }

+	}

+      }

+    }

+  }

+}

+

+

+LOCAL(void)

+do_transverse (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,

+	       JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,

+	       jvirt_barray_ptr *src_coef_arrays,

+	       jvirt_barray_ptr *dst_coef_arrays)

+/* Transverse transpose is equivalent to

+ *   1. 180 degree rotation;

+ *   2. Transposition;

+ * or

+ *   1. Horizontal mirroring;

+ *   2. Transposition;

+ *   3. Horizontal mirroring.

+ * These steps are merged into a single processing routine.

+ */

+{

+  JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height, dst_blk_x, dst_blk_y;

+  JDIMENSION x_crop_blocks, y_crop_blocks;

+  int ci, i, j, offset_x, offset_y;

+  JBLOCKARRAY src_buffer, dst_buffer;

+  JCOEFPTR src_ptr, dst_ptr;

+  jpeg_component_info *compptr;

+

+  MCU_cols = srcinfo->output_height /

+    (dstinfo->max_h_samp_factor * dstinfo->min_DCT_h_scaled_size);

+  MCU_rows = srcinfo->output_width /

+    (dstinfo->max_v_samp_factor * dstinfo->min_DCT_v_scaled_size);

+

+  for (ci = 0; ci < dstinfo->num_components; ci++) {

+    compptr = dstinfo->comp_info + ci;

+    comp_width = MCU_cols * compptr->h_samp_factor;

+    comp_height = MCU_rows * compptr->v_samp_factor;

+    x_crop_blocks = x_crop_offset * compptr->h_samp_factor;

+    y_crop_blocks = y_crop_offset * compptr->v_samp_factor;

+    for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;

+	 dst_blk_y += compptr->v_samp_factor) {

+      dst_buffer = (*srcinfo->mem->access_virt_barray)

+	((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,

+	 (JDIMENSION) compptr->v_samp_factor, TRUE);

+      for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {

+	for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;

+	     dst_blk_x += compptr->h_samp_factor) {

+	  if (x_crop_blocks + dst_blk_x < comp_width) {

+	    /* Block is within the mirrorable area. */

+	    src_buffer = (*srcinfo->mem->access_virt_barray)

+	      ((j_common_ptr) srcinfo, src_coef_arrays[ci],

+	       comp_width - x_crop_blocks - dst_blk_x -

+	       (JDIMENSION) compptr->h_samp_factor,

+	       (JDIMENSION) compptr->h_samp_factor, FALSE);

+	  } else {

+	    src_buffer = (*srcinfo->mem->access_virt_barray)

+	      ((j_common_ptr) srcinfo, src_coef_arrays[ci],

+	       dst_blk_x + x_crop_blocks,

+	       (JDIMENSION) compptr->h_samp_factor, FALSE);

+	  }

+	  for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {

+	    dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];

+	    if (y_crop_blocks + dst_blk_y < comp_height) {

+	      if (x_crop_blocks + dst_blk_x < comp_width) {

+		/* Block is within the mirrorable area. */

+		src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]

+		  [comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];

+		for (i = 0; i < DCTSIZE; i++) {

+		  for (j = 0; j < DCTSIZE; j++) {

+		    dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];

+		    j++;

+		    dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];

+		  }

+		  i++;

+		  for (j = 0; j < DCTSIZE; j++) {

+		    dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];

+		    j++;

+		    dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];

+		  }

+		}

+	      } else {

+		/* Right-edge blocks are mirrored in y only */

+		src_ptr = src_buffer[offset_x]

+		  [comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];

+		for (i = 0; i < DCTSIZE; i++) {

+		  for (j = 0; j < DCTSIZE; j++) {

+		    dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];

+		    j++;

+		    dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];

+		  }

+		}

+	      }

+	    } else {

+	      if (x_crop_blocks + dst_blk_x < comp_width) {

+		/* Bottom-edge blocks are mirrored in x only */

+		src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]

+		  [dst_blk_y + offset_y + y_crop_blocks];

+		for (i = 0; i < DCTSIZE; i++) {

+		  for (j = 0; j < DCTSIZE; j++)

+		    dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];

+		  i++;

+		  for (j = 0; j < DCTSIZE; j++)

+		    dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];

+		}

+	      } else {

+		/* At lower right corner, just transpose, no mirroring */

+		src_ptr = src_buffer[offset_x]

+		  [dst_blk_y + offset_y + y_crop_blocks];

+		for (i = 0; i < DCTSIZE; i++)

+		  for (j = 0; j < DCTSIZE; j++)

+		    dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];

+	      }

+	    }

+	  }

+	}

+      }

+    }

+  }

+}

+

+

+/* Parse an unsigned integer: subroutine for jtransform_parse_crop_spec.

+ * Returns TRUE if valid integer found, FALSE if not.

+ * *strptr is advanced over the digit string, and *result is set to its value.

+ */

+

+LOCAL(boolean)

+jt_read_integer (const char ** strptr, JDIMENSION * result)

+{

+  const char * ptr = *strptr;

+  JDIMENSION val = 0;

+

+  for (; isdigit(*ptr); ptr++) {

+    val = val * 10 + (JDIMENSION) (*ptr - '0');

+  }

+  *result = val;

+  if (ptr == *strptr)

+    return FALSE;		/* oops, no digits */

+  *strptr = ptr;

+  return TRUE;

+}

+

+

+/* Parse a crop specification (written in X11 geometry style).

+ * The routine returns TRUE if the spec string is valid, FALSE if not.

+ *

+ * The crop spec string should have the format

+ *	<width>[f]x<height>[f]{+-}<xoffset>{+-}<yoffset>

+ * where width, height, xoffset, and yoffset are unsigned integers.

+ * Each of the elements can be omitted to indicate a default value.

+ * (A weakness of this style is that it is not possible to omit xoffset

+ * while specifying yoffset, since they look alike.)

+ *

+ * This code is loosely based on XParseGeometry from the X11 distribution.

+ */

+

+GLOBAL(boolean)

+jtransform_parse_crop_spec (jpeg_transform_info *info, const char *spec)

+{

+  info->crop = FALSE;

+  info->crop_width_set = JCROP_UNSET;

+  info->crop_height_set = JCROP_UNSET;

+  info->crop_xoffset_set = JCROP_UNSET;

+  info->crop_yoffset_set = JCROP_UNSET;

+

+  if (isdigit(*spec)) {

+    /* fetch width */

+    if (! jt_read_integer(&spec, &info->crop_width))

+      return FALSE;

+    if (*spec == 'f' || *spec == 'F') {

+      spec++;

+      info->crop_width_set = JCROP_FORCE;

+    } else

+      info->crop_width_set = JCROP_POS;

+  }

+  if (*spec == 'x' || *spec == 'X') {

+    /* fetch height */

+    spec++;

+    if (! jt_read_integer(&spec, &info->crop_height))

+      return FALSE;

+    if (*spec == 'f' || *spec == 'F') {

+      spec++;

+      info->crop_height_set = JCROP_FORCE;

+    } else

+      info->crop_height_set = JCROP_POS;

+  }

+  if (*spec == '+' || *spec == '-') {

+    /* fetch xoffset */

+    info->crop_xoffset_set = (*spec == '-') ? JCROP_NEG : JCROP_POS;

+    spec++;

+    if (! jt_read_integer(&spec, &info->crop_xoffset))

+      return FALSE;

+  }

+  if (*spec == '+' || *spec == '-') {

+    /* fetch yoffset */

+    info->crop_yoffset_set = (*spec == '-') ? JCROP_NEG : JCROP_POS;

+    spec++;

+    if (! jt_read_integer(&spec, &info->crop_yoffset))

+      return FALSE;

+  }

+  /* We had better have gotten to the end of the string. */

+  if (*spec != '\0')

+    return FALSE;

+  info->crop = TRUE;

+  return TRUE;

+}

+

+

+/* Trim off any partial iMCUs on the indicated destination edge */

+

+LOCAL(void)

+trim_right_edge (jpeg_transform_info *info, JDIMENSION full_width)

+{

+  JDIMENSION MCU_cols;

+

+  MCU_cols = info->output_width / info->iMCU_sample_width;

+  if (MCU_cols > 0 && info->x_crop_offset + MCU_cols ==

+      full_width / info->iMCU_sample_width)

+    info->output_width = MCU_cols * info->iMCU_sample_width;

+}

+

+LOCAL(void)

+trim_bottom_edge (jpeg_transform_info *info, JDIMENSION full_height)

+{

+  JDIMENSION MCU_rows;

+

+  MCU_rows = info->output_height / info->iMCU_sample_height;

+  if (MCU_rows > 0 && info->y_crop_offset + MCU_rows ==

+      full_height / info->iMCU_sample_height)

+    info->output_height = MCU_rows * info->iMCU_sample_height;

+}

+

+

+/* Request any required workspace.

+ *

+ * This routine figures out the size that the output image will be

+ * (which implies that all the transform parameters must be set before

+ * it is called).

+ *

+ * We allocate the workspace virtual arrays from the source decompression

+ * object, so that all the arrays (both the original data and the workspace)

+ * will be taken into account while making memory management decisions.

+ * Hence, this routine must be called after jpeg_read_header (which reads

+ * the image dimensions) and before jpeg_read_coefficients (which realizes

+ * the source's virtual arrays).

+ *

+ * This function returns FALSE right away if -perfect is given

+ * and transformation is not perfect.  Otherwise returns TRUE.

+ */

+

+GLOBAL(boolean)

+jtransform_request_workspace (j_decompress_ptr srcinfo,

+			      jpeg_transform_info *info)

+{

+  jvirt_barray_ptr *coef_arrays;

+  boolean need_workspace, transpose_it;

+  jpeg_component_info *compptr;

+  JDIMENSION xoffset, yoffset;

+  JDIMENSION width_in_iMCUs, height_in_iMCUs;

+  JDIMENSION width_in_blocks, height_in_blocks;

+  int ci, h_samp_factor, v_samp_factor;

+

+  /* Determine number of components in output image */

+  if (info->force_grayscale &&

+      srcinfo->jpeg_color_space == JCS_YCbCr &&

+      srcinfo->num_components == 3)

+    /* We'll only process the first component */

+    info->num_components = 1;

+  else

+    /* Process all the components */

+    info->num_components = srcinfo->num_components;

+

+  /* Compute output image dimensions and related values. */

+  jpeg_core_output_dimensions(srcinfo);

+

+  /* Return right away if -perfect is given and transformation is not perfect.

+   */

+  if (info->perfect) {

+    if (info->num_components == 1) {

+      if (!jtransform_perfect_transform(srcinfo->output_width,

+	  srcinfo->output_height,

+	  srcinfo->min_DCT_h_scaled_size,

+	  srcinfo->min_DCT_v_scaled_size,

+	  info->transform))

+	return FALSE;

+    } else {

+      if (!jtransform_perfect_transform(srcinfo->output_width,

+	  srcinfo->output_height,

+	  srcinfo->max_h_samp_factor * srcinfo->min_DCT_h_scaled_size,

+	  srcinfo->max_v_samp_factor * srcinfo->min_DCT_v_scaled_size,

+	  info->transform))

+	return FALSE;

+    }

+  }

+

+  /* If there is only one output component, force the iMCU size to be 1;

+   * else use the source iMCU size.  (This allows us to do the right thing

+   * when reducing color to grayscale, and also provides a handy way of

+   * cleaning up "funny" grayscale images whose sampling factors are not 1x1.)

+   */

+  switch (info->transform) {

+  case JXFORM_TRANSPOSE:

+  case JXFORM_TRANSVERSE:

+  case JXFORM_ROT_90:

+  case JXFORM_ROT_270:

+    info->output_width = srcinfo->output_height;

+    info->output_height = srcinfo->output_width;

+    if (info->num_components == 1) {

+      info->iMCU_sample_width = srcinfo->min_DCT_v_scaled_size;

+      info->iMCU_sample_height = srcinfo->min_DCT_h_scaled_size;

+    } else {

+      info->iMCU_sample_width =

+	srcinfo->max_v_samp_factor * srcinfo->min_DCT_v_scaled_size;

+      info->iMCU_sample_height =

+	srcinfo->max_h_samp_factor * srcinfo->min_DCT_h_scaled_size;

+    }

+    break;

+  default:

+    info->output_width = srcinfo->output_width;

+    info->output_height = srcinfo->output_height;

+    if (info->num_components == 1) {

+      info->iMCU_sample_width = srcinfo->min_DCT_h_scaled_size;

+      info->iMCU_sample_height = srcinfo->min_DCT_v_scaled_size;

+    } else {

+      info->iMCU_sample_width =

+	srcinfo->max_h_samp_factor * srcinfo->min_DCT_h_scaled_size;

+      info->iMCU_sample_height =

+	srcinfo->max_v_samp_factor * srcinfo->min_DCT_v_scaled_size;

+    }

+    break;

+  }

+

+  /* If cropping has been requested, compute the crop area's position and

+   * dimensions, ensuring that its upper left corner falls at an iMCU boundary.

+   */

+  if (info->crop) {

+    /* Insert default values for unset crop parameters */

+    if (info->crop_xoffset_set == JCROP_UNSET)

+      info->crop_xoffset = 0;	/* default to +0 */

+    if (info->crop_yoffset_set == JCROP_UNSET)

+      info->crop_yoffset = 0;	/* default to +0 */

+    if (info->crop_xoffset >= info->output_width ||

+	info->crop_yoffset >= info->output_height)

+      ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);

+    if (info->crop_width_set == JCROP_UNSET)

+      info->crop_width = info->output_width - info->crop_xoffset;

+    if (info->crop_height_set == JCROP_UNSET)

+      info->crop_height = info->output_height - info->crop_yoffset;

+    /* Ensure parameters are valid */

+    if (info->crop_width <= 0 || info->crop_width > info->output_width ||

+	info->crop_height <= 0 || info->crop_height > info->output_height ||

+	info->crop_xoffset > info->output_width - info->crop_width ||

+	info->crop_yoffset > info->output_height - info->crop_height)

+      ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);

+    /* Convert negative crop offsets into regular offsets */

+    if (info->crop_xoffset_set == JCROP_NEG)

+      xoffset = info->output_width - info->crop_width - info->crop_xoffset;

+    else

+      xoffset = info->crop_xoffset;

+    if (info->crop_yoffset_set == JCROP_NEG)

+      yoffset = info->output_height - info->crop_height - info->crop_yoffset;

+    else

+      yoffset = info->crop_yoffset;

+    /* Now adjust so that upper left corner falls at an iMCU boundary */

+    if (info->crop_width_set == JCROP_FORCE)

+      info->output_width = info->crop_width;

+    else

+      info->output_width =

+        info->crop_width + (xoffset % info->iMCU_sample_width);

+    if (info->crop_height_set == JCROP_FORCE)

+      info->output_height = info->crop_height;

+    else

+      info->output_height =

+        info->crop_height + (yoffset % info->iMCU_sample_height);

+    /* Save x/y offsets measured in iMCUs */

+    info->x_crop_offset = xoffset / info->iMCU_sample_width;

+    info->y_crop_offset = yoffset / info->iMCU_sample_height;

+  } else {

+    info->x_crop_offset = 0;

+    info->y_crop_offset = 0;

+  }

+

+  /* Figure out whether we need workspace arrays,

+   * and if so whether they are transposed relative to the source.

+   */

+  need_workspace = FALSE;

+  transpose_it = FALSE;

+  switch (info->transform) {

+  case JXFORM_NONE:

+    if (info->x_crop_offset != 0 || info->y_crop_offset != 0)

+      need_workspace = TRUE;

+    /* No workspace needed if neither cropping nor transforming */

+    break;

+  case JXFORM_FLIP_H:

+    if (info->trim)

+      trim_right_edge(info, srcinfo->output_width);

+    if (info->y_crop_offset != 0)

+      need_workspace = TRUE;

+    /* do_flip_h_no_crop doesn't need a workspace array */

+    break;

+  case JXFORM_FLIP_V:

+    if (info->trim)

+      trim_bottom_edge(info, srcinfo->output_height);

+    /* Need workspace arrays having same dimensions as source image. */

+    need_workspace = TRUE;

+    break;

+  case JXFORM_TRANSPOSE:

+    /* transpose does NOT have to trim anything */

+    /* Need workspace arrays having transposed dimensions. */

+    need_workspace = TRUE;

+    transpose_it = TRUE;

+    break;

+  case JXFORM_TRANSVERSE:

+    if (info->trim) {

+      trim_right_edge(info, srcinfo->output_height);

+      trim_bottom_edge(info, srcinfo->output_width);

+    }

+    /* Need workspace arrays having transposed dimensions. */

+    need_workspace = TRUE;

+    transpose_it = TRUE;

+    break;

+  case JXFORM_ROT_90:

+    if (info->trim)

+      trim_right_edge(info, srcinfo->output_height);

+    /* Need workspace arrays having transposed dimensions. */

+    need_workspace = TRUE;

+    transpose_it = TRUE;

+    break;

+  case JXFORM_ROT_180:

+    if (info->trim) {

+      trim_right_edge(info, srcinfo->output_width);

+      trim_bottom_edge(info, srcinfo->output_height);

+    }

+    /* Need workspace arrays having same dimensions as source image. */

+    need_workspace = TRUE;

+    break;

+  case JXFORM_ROT_270:

+    if (info->trim)

+      trim_bottom_edge(info, srcinfo->output_width);

+    /* Need workspace arrays having transposed dimensions. */

+    need_workspace = TRUE;

+    transpose_it = TRUE;

+    break;

+  }

+

+  /* Allocate workspace if needed.

+   * Note that we allocate arrays padded out to the next iMCU boundary,

+   * so that transform routines need not worry about missing edge blocks.

+   */

+  if (need_workspace) {

+    coef_arrays = (jvirt_barray_ptr *)

+      (*srcinfo->mem->alloc_small) ((j_common_ptr) srcinfo, JPOOL_IMAGE,

+	SIZEOF(jvirt_barray_ptr) * info->num_components);

+    width_in_iMCUs = (JDIMENSION)

+      jdiv_round_up((long) info->output_width,

+		    (long) info->iMCU_sample_width);

+    height_in_iMCUs = (JDIMENSION)

+      jdiv_round_up((long) info->output_height,

+		    (long) info->iMCU_sample_height);

+    for (ci = 0; ci < info->num_components; ci++) {

+      compptr = srcinfo->comp_info + ci;

+      if (info->num_components == 1) {

+	/* we're going to force samp factors to 1x1 in this case */

+	h_samp_factor = v_samp_factor = 1;

+      } else if (transpose_it) {

+	h_samp_factor = compptr->v_samp_factor;

+	v_samp_factor = compptr->h_samp_factor;

+      } else {

+	h_samp_factor = compptr->h_samp_factor;

+	v_samp_factor = compptr->v_samp_factor;

+      }

+      width_in_blocks = width_in_iMCUs * h_samp_factor;

+      height_in_blocks = height_in_iMCUs * v_samp_factor;

+      coef_arrays[ci] = (*srcinfo->mem->request_virt_barray)

+	((j_common_ptr) srcinfo, JPOOL_IMAGE, FALSE,

+	 width_in_blocks, height_in_blocks, (JDIMENSION) v_samp_factor);

+    }

+    info->workspace_coef_arrays = coef_arrays;

+  } else

+    info->workspace_coef_arrays = NULL;

+

+  return TRUE;

+}

+

+

+/* Transpose destination image parameters */

+

+LOCAL(void)

+transpose_critical_parameters (j_compress_ptr dstinfo)

+{

+  int tblno, i, j, ci, itemp;

+  jpeg_component_info *compptr;

+  JQUANT_TBL *qtblptr;

+  JDIMENSION jtemp;

+  UINT16 qtemp;

+

+  /* Transpose image dimensions */

+  jtemp = dstinfo->image_width;

+  dstinfo->image_width = dstinfo->image_height;

+  dstinfo->image_height = jtemp;

+  itemp = dstinfo->min_DCT_h_scaled_size;

+  dstinfo->min_DCT_h_scaled_size = dstinfo->min_DCT_v_scaled_size;

+  dstinfo->min_DCT_v_scaled_size = itemp;

+

+  /* Transpose sampling factors */

+  for (ci = 0; ci < dstinfo->num_components; ci++) {

+    compptr = dstinfo->comp_info + ci;

+    itemp = compptr->h_samp_factor;

+    compptr->h_samp_factor = compptr->v_samp_factor;

+    compptr->v_samp_factor = itemp;

+  }

+

+  /* Transpose quantization tables */

+  for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) {

+    qtblptr = dstinfo->quant_tbl_ptrs[tblno];

+    if (qtblptr != NULL) {

+      for (i = 0; i < DCTSIZE; i++) {

+	for (j = 0; j < i; j++) {

+	  qtemp = qtblptr->quantval[i*DCTSIZE+j];

+	  qtblptr->quantval[i*DCTSIZE+j] = qtblptr->quantval[j*DCTSIZE+i];

+	  qtblptr->quantval[j*DCTSIZE+i] = qtemp;

+	}

+      }

+    }

+  }

+}

+

+

+/* Adjust Exif image parameters.

+ *

+ * We try to adjust the Tags ExifImageWidth and ExifImageHeight if possible.

+ */

+

+LOCAL(void)

+adjust_exif_parameters (JOCTET FAR * data, unsigned int length,

+			JDIMENSION new_width, JDIMENSION new_height)

+{

+  boolean is_motorola; /* Flag for byte order */

+  unsigned int number_of_tags, tagnum;

+  unsigned int firstoffset, offset;

+  JDIMENSION new_value;

+

+  if (length < 12) return; /* Length of an IFD entry */

+

+  /* Discover byte order */

+  if (GETJOCTET(data[0]) == 0x49 && GETJOCTET(data[1]) == 0x49)

+    is_motorola = FALSE;

+  else if (GETJOCTET(data[0]) == 0x4D && GETJOCTET(data[1]) == 0x4D)

+    is_motorola = TRUE;

+  else

+    return;

+

+  /* Check Tag Mark */

+  if (is_motorola) {

+    if (GETJOCTET(data[2]) != 0) return;

+    if (GETJOCTET(data[3]) != 0x2A) return;

+  } else {

+    if (GETJOCTET(data[3]) != 0) return;

+    if (GETJOCTET(data[2]) != 0x2A) return;

+  }

+

+  /* Get first IFD offset (offset to IFD0) */

+  if (is_motorola) {

+    if (GETJOCTET(data[4]) != 0) return;

+    if (GETJOCTET(data[5]) != 0) return;

+    firstoffset = GETJOCTET(data[6]);

+    firstoffset <<= 8;

+    firstoffset += GETJOCTET(data[7]);

+  } else {

+    if (GETJOCTET(data[7]) != 0) return;

+    if (GETJOCTET(data[6]) != 0) return;

+    firstoffset = GETJOCTET(data[5]);

+    firstoffset <<= 8;

+    firstoffset += GETJOCTET(data[4]);

+  }

+  if (firstoffset > length - 2) return; /* check end of data segment */

+

+  /* Get the number of directory entries contained in this IFD */

+  if (is_motorola) {

+    number_of_tags = GETJOCTET(data[firstoffset]);

+    number_of_tags <<= 8;

+    number_of_tags += GETJOCTET(data[firstoffset+1]);

+  } else {

+    number_of_tags = GETJOCTET(data[firstoffset+1]);

+    number_of_tags <<= 8;

+    number_of_tags += GETJOCTET(data[firstoffset]);

+  }

+  if (number_of_tags == 0) return;

+  firstoffset += 2;

+

+  /* Search for ExifSubIFD offset Tag in IFD0 */

+  for (;;) {

+    if (firstoffset > length - 12) return; /* check end of data segment */

+    /* Get Tag number */

+    if (is_motorola) {

+      tagnum = GETJOCTET(data[firstoffset]);

+      tagnum <<= 8;

+      tagnum += GETJOCTET(data[firstoffset+1]);

+    } else {

+      tagnum = GETJOCTET(data[firstoffset+1]);

+      tagnum <<= 8;

+      tagnum += GETJOCTET(data[firstoffset]);

+    }

+    if (tagnum == 0x8769) break; /* found ExifSubIFD offset Tag */

+    if (--number_of_tags == 0) return;

+    firstoffset += 12;

+  }

+

+  /* Get the ExifSubIFD offset */

+  if (is_motorola) {

+    if (GETJOCTET(data[firstoffset+8]) != 0) return;

+    if (GETJOCTET(data[firstoffset+9]) != 0) return;

+    offset = GETJOCTET(data[firstoffset+10]);

+    offset <<= 8;

+    offset += GETJOCTET(data[firstoffset+11]);

+  } else {

+    if (GETJOCTET(data[firstoffset+11]) != 0) return;

+    if (GETJOCTET(data[firstoffset+10]) != 0) return;

+    offset = GETJOCTET(data[firstoffset+9]);

+    offset <<= 8;

+    offset += GETJOCTET(data[firstoffset+8]);

+  }

+  if (offset > length - 2) return; /* check end of data segment */

+

+  /* Get the number of directory entries contained in this SubIFD */

+  if (is_motorola) {

+    number_of_tags = GETJOCTET(data[offset]);

+    number_of_tags <<= 8;

+    number_of_tags += GETJOCTET(data[offset+1]);

+  } else {

+    number_of_tags = GETJOCTET(data[offset+1]);

+    number_of_tags <<= 8;

+    number_of_tags += GETJOCTET(data[offset]);

+  }

+  if (number_of_tags < 2) return;

+  offset += 2;

+

+  /* Search for ExifImageWidth and ExifImageHeight Tags in this SubIFD */

+  do {

+    if (offset > length - 12) return; /* check end of data segment */

+    /* Get Tag number */

+    if (is_motorola) {

+      tagnum = GETJOCTET(data[offset]);

+      tagnum <<= 8;

+      tagnum += GETJOCTET(data[offset+1]);

+    } else {

+      tagnum = GETJOCTET(data[offset+1]);

+      tagnum <<= 8;

+      tagnum += GETJOCTET(data[offset]);

+    }

+    if (tagnum == 0xA002 || tagnum == 0xA003) {

+      if (tagnum == 0xA002)

+	new_value = new_width; /* ExifImageWidth Tag */

+      else

+	new_value = new_height; /* ExifImageHeight Tag */

+      if (is_motorola) {

+	data[offset+2] = 0; /* Format = unsigned long (4 octets) */

+	data[offset+3] = 4;

+	data[offset+4] = 0; /* Number Of Components = 1 */

+	data[offset+5] = 0;

+	data[offset+6] = 0;

+	data[offset+7] = 1;

+	data[offset+8] = 0;

+	data[offset+9] = 0;

+	data[offset+10] = (JOCTET)((new_value >> 8) & 0xFF);

+	data[offset+11] = (JOCTET)(new_value & 0xFF);

+      } else {

+	data[offset+2] = 4; /* Format = unsigned long (4 octets) */

+	data[offset+3] = 0;

+	data[offset+4] = 1; /* Number Of Components = 1 */

+	data[offset+5] = 0;

+	data[offset+6] = 0;

+	data[offset+7] = 0;

+	data[offset+8] = (JOCTET)(new_value & 0xFF);

+	data[offset+9] = (JOCTET)((new_value >> 8) & 0xFF);

+	data[offset+10] = 0;

+	data[offset+11] = 0;

+      }

+    }

+    offset += 12;

+  } while (--number_of_tags);

+}

+

+

+/* Adjust output image parameters as needed.

+ *

+ * This must be called after jpeg_copy_critical_parameters()

+ * and before jpeg_write_coefficients().

+ *

+ * The return value is the set of virtual coefficient arrays to be written

+ * (either the ones allocated by jtransform_request_workspace, or the

+ * original source data arrays).  The caller will need to pass this value

+ * to jpeg_write_coefficients().

+ */

+

+GLOBAL(jvirt_barray_ptr *)

+jtransform_adjust_parameters (j_decompress_ptr srcinfo,

+			      j_compress_ptr dstinfo,

+			      jvirt_barray_ptr *src_coef_arrays,

+			      jpeg_transform_info *info)

+{

+  /* If force-to-grayscale is requested, adjust destination parameters */

+  if (info->force_grayscale) {

+    /* First, ensure we have YCbCr or grayscale data, and that the source's

+     * Y channel is full resolution.  (No reasonable person would make Y

+     * be less than full resolution, so actually coping with that case

+     * isn't worth extra code space.  But we check it to avoid crashing.)

+     */

+    if (((dstinfo->jpeg_color_space == JCS_YCbCr &&

+	  dstinfo->num_components == 3) ||

+	 (dstinfo->jpeg_color_space == JCS_GRAYSCALE &&

+	  dstinfo->num_components == 1)) &&

+	srcinfo->comp_info[0].h_samp_factor == srcinfo->max_h_samp_factor &&

+	srcinfo->comp_info[0].v_samp_factor == srcinfo->max_v_samp_factor) {

+      /* We use jpeg_set_colorspace to make sure subsidiary settings get fixed

+       * properly.  Among other things, it sets the target h_samp_factor &

+       * v_samp_factor to 1, which typically won't match the source.

+       * We have to preserve the source's quantization table number, however.

+       */

+      int sv_quant_tbl_no = dstinfo->comp_info[0].quant_tbl_no;

+      jpeg_set_colorspace(dstinfo, JCS_GRAYSCALE);

+      dstinfo->comp_info[0].quant_tbl_no = sv_quant_tbl_no;

+    } else {

+      /* Sorry, can't do it */

+      ERREXIT(dstinfo, JERR_CONVERSION_NOTIMPL);

+    }

+  } else if (info->num_components == 1) {

+    /* For a single-component source, we force the destination sampling factors

+     * to 1x1, with or without force_grayscale.  This is useful because some

+     * decoders choke on grayscale images with other sampling factors.

+     */

+    dstinfo->comp_info[0].h_samp_factor = 1;

+    dstinfo->comp_info[0].v_samp_factor = 1;

+  }

+

+  /* Correct the destination's image dimensions as necessary

+   * for rotate/flip, resize, and crop operations.

+   */

+  dstinfo->jpeg_width = info->output_width;

+  dstinfo->jpeg_height = info->output_height;

+

+  /* Transpose destination image parameters */

+  switch (info->transform) {

+  case JXFORM_TRANSPOSE:

+  case JXFORM_TRANSVERSE:

+  case JXFORM_ROT_90:

+  case JXFORM_ROT_270:

+    transpose_critical_parameters(dstinfo);

+    break;

+  default:

+    break;

+  }

+

+  /* Adjust Exif properties */

+  if (srcinfo->marker_list != NULL &&

+      srcinfo->marker_list->marker == JPEG_APP0+1 &&

+      srcinfo->marker_list->data_length >= 6 &&

+      GETJOCTET(srcinfo->marker_list->data[0]) == 0x45 &&

+      GETJOCTET(srcinfo->marker_list->data[1]) == 0x78 &&

+      GETJOCTET(srcinfo->marker_list->data[2]) == 0x69 &&

+      GETJOCTET(srcinfo->marker_list->data[3]) == 0x66 &&

+      GETJOCTET(srcinfo->marker_list->data[4]) == 0 &&

+      GETJOCTET(srcinfo->marker_list->data[5]) == 0) {

+    /* Suppress output of JFIF marker */

+    dstinfo->write_JFIF_header = FALSE;

+    /* Adjust Exif image parameters */

+    if (dstinfo->jpeg_width != srcinfo->image_width ||

+	dstinfo->jpeg_height != srcinfo->image_height)

+      /* Align data segment to start of TIFF structure for parsing */

+      adjust_exif_parameters(srcinfo->marker_list->data + 6,

+	srcinfo->marker_list->data_length - 6,

+	dstinfo->jpeg_width, dstinfo->jpeg_height);

+  }

+

+  /* Return the appropriate output data set */

+  if (info->workspace_coef_arrays != NULL)

+    return info->workspace_coef_arrays;

+  return src_coef_arrays;

+}

+

+

+/* Execute the actual transformation, if any.

+ *

+ * This must be called *after* jpeg_write_coefficients, because it depends

+ * on jpeg_write_coefficients to have computed subsidiary values such as

+ * the per-component width and height fields in the destination object.

+ *

+ * Note that some transformations will modify the source data arrays!

+ */

+

+GLOBAL(void)

+jtransform_execute_transform (j_decompress_ptr srcinfo,

+			      j_compress_ptr dstinfo,

+			      jvirt_barray_ptr *src_coef_arrays,

+			      jpeg_transform_info *info)

+{

+  jvirt_barray_ptr *dst_coef_arrays = info->workspace_coef_arrays;

+

+  /* Note: conditions tested here should match those in switch statement

+   * in jtransform_request_workspace()

+   */

+  switch (info->transform) {

+  case JXFORM_NONE:

+    if (info->x_crop_offset != 0 || info->y_crop_offset != 0)

+      do_crop(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,

+	      src_coef_arrays, dst_coef_arrays);

+    break;

+  case JXFORM_FLIP_H:

+    if (info->y_crop_offset != 0)

+      do_flip_h(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,

+		src_coef_arrays, dst_coef_arrays);

+    else

+      do_flip_h_no_crop(srcinfo, dstinfo, info->x_crop_offset,

+			src_coef_arrays);

+    break;

+  case JXFORM_FLIP_V:

+    do_flip_v(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,

+	      src_coef_arrays, dst_coef_arrays);

+    break;

+  case JXFORM_TRANSPOSE:

+    do_transpose(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,

+		 src_coef_arrays, dst_coef_arrays);

+    break;

+  case JXFORM_TRANSVERSE:

+    do_transverse(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,

+		  src_coef_arrays, dst_coef_arrays);

+    break;

+  case JXFORM_ROT_90:

+    do_rot_90(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,

+	      src_coef_arrays, dst_coef_arrays);

+    break;

+  case JXFORM_ROT_180:

+    do_rot_180(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,

+	       src_coef_arrays, dst_coef_arrays);

+    break;

+  case JXFORM_ROT_270:

+    do_rot_270(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,

+	       src_coef_arrays, dst_coef_arrays);

+    break;

+  }

+}

+

+/* jtransform_perfect_transform

+ *

+ * Determine whether lossless transformation is perfectly

+ * possible for a specified image and transformation.

+ *

+ * Inputs:

+ *   image_width, image_height: source image dimensions.

+ *   MCU_width, MCU_height: pixel dimensions of MCU.

+ *   transform: transformation identifier.

+ * Parameter sources from initialized jpeg_struct

+ * (after reading source header):

+ *   image_width = cinfo.image_width

+ *   image_height = cinfo.image_height

+ *   MCU_width = cinfo.max_h_samp_factor * cinfo.block_size

+ *   MCU_height = cinfo.max_v_samp_factor * cinfo.block_size

+ * Result:

+ *   TRUE = perfect transformation possible

+ *   FALSE = perfect transformation not possible

+ *           (may use custom action then)

+ */

+

+GLOBAL(boolean)

+jtransform_perfect_transform(JDIMENSION image_width, JDIMENSION image_height,

+			     int MCU_width, int MCU_height,

+			     JXFORM_CODE transform)

+{

+  boolean result = TRUE; /* initialize TRUE */

+

+  switch (transform) {

+  case JXFORM_FLIP_H:

+  case JXFORM_ROT_270:

+    if (image_width % (JDIMENSION) MCU_width)

+      result = FALSE;

+    break;

+  case JXFORM_FLIP_V:

+  case JXFORM_ROT_90:

+    if (image_height % (JDIMENSION) MCU_height)

+      result = FALSE;

+    break;

+  case JXFORM_TRANSVERSE:

+  case JXFORM_ROT_180:

+    if (image_width % (JDIMENSION) MCU_width)

+      result = FALSE;

+    if (image_height % (JDIMENSION) MCU_height)

+      result = FALSE;

+    break;

+  default:

+    break;

+  }

+

+  return result;

+}

+

+#endif /* TRANSFORMS_SUPPORTED */

+

+

+/* Setup decompression object to save desired markers in memory.

+ * This must be called before jpeg_read_header() to have the desired effect.

+ */

+

+GLOBAL(void)

+jcopy_markers_setup (j_decompress_ptr srcinfo, JCOPY_OPTION option)

+{

+#ifdef SAVE_MARKERS_SUPPORTED

+  int m;

+

+  /* Save comments except under NONE option */

+  if (option != JCOPYOPT_NONE) {

+    jpeg_save_markers(srcinfo, JPEG_COM, 0xFFFF);

+  }

+  /* Save all types of APPn markers iff ALL option */

+  if (option == JCOPYOPT_ALL) {

+    for (m = 0; m < 16; m++)

+      jpeg_save_markers(srcinfo, JPEG_APP0 + m, 0xFFFF);

+  }

+#endif /* SAVE_MARKERS_SUPPORTED */

+}

+

+/* Copy markers saved in the given source object to the destination object.

+ * This should be called just after jpeg_start_compress() or

+ * jpeg_write_coefficients().

+ * Note that those routines will have written the SOI, and also the

+ * JFIF APP0 or Adobe APP14 markers if selected.

+ */

+

+GLOBAL(void)

+jcopy_markers_execute (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,

+		       JCOPY_OPTION option)

+{

+  jpeg_saved_marker_ptr marker;

+

+  /* In the current implementation, we don't actually need to examine the

+   * option flag here; we just copy everything that got saved.

+   * But to avoid confusion, we do not output JFIF and Adobe APP14 markers

+   * if the encoder library already wrote one.

+   */

+  for (marker = srcinfo->marker_list; marker != NULL; marker = marker->next) {

+    if (dstinfo->write_JFIF_header &&

+	marker->marker == JPEG_APP0 &&

+	marker->data_length >= 5 &&

+	GETJOCTET(marker->data[0]) == 0x4A &&

+	GETJOCTET(marker->data[1]) == 0x46 &&

+	GETJOCTET(marker->data[2]) == 0x49 &&

+	GETJOCTET(marker->data[3]) == 0x46 &&

+	GETJOCTET(marker->data[4]) == 0)

+      continue;			/* reject duplicate JFIF */

+    if (dstinfo->write_Adobe_marker &&

+	marker->marker == JPEG_APP0+14 &&

+	marker->data_length >= 5 &&

+	GETJOCTET(marker->data[0]) == 0x41 &&

+	GETJOCTET(marker->data[1]) == 0x64 &&

+	GETJOCTET(marker->data[2]) == 0x6F &&

+	GETJOCTET(marker->data[3]) == 0x62 &&

+	GETJOCTET(marker->data[4]) == 0x65)

+      continue;			/* reject duplicate Adobe */

+#ifdef NEED_FAR_POINTERS

+    /* We could use jpeg_write_marker if the data weren't FAR... */

+    {

+      unsigned int i;

+      jpeg_write_m_header(dstinfo, marker->marker, marker->data_length);

+      for (i = 0; i < marker->data_length; i++)

+	jpeg_write_m_byte(dstinfo, marker->data[i]);

+    }

+#else

+    jpeg_write_marker(dstinfo, marker->marker,

+		      marker->data, marker->data_length);

+#endif

+  }

+}