diff options
Diffstat (limited to 'plugins/FreeImage/Source/LibJPEG/jdsample.c')
| -rw-r--r-- | plugins/FreeImage/Source/LibJPEG/jdsample.c | 722 | 
1 files changed, 361 insertions, 361 deletions
diff --git a/plugins/FreeImage/Source/LibJPEG/jdsample.c b/plugins/FreeImage/Source/LibJPEG/jdsample.c index 94f9599f04..7bc8885b02 100644 --- a/plugins/FreeImage/Source/LibJPEG/jdsample.c +++ b/plugins/FreeImage/Source/LibJPEG/jdsample.c @@ -1,361 +1,361 @@ -/*
 - * jdsample.c
 - *
 - * Copyright (C) 1991-1996, Thomas G. Lane.
 - * Modified 2002-2008 by 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 upsampling routines.
 - *
 - * Upsampling input data is counted in "row groups".  A row group
 - * is defined to be (v_samp_factor * DCT_v_scaled_size / min_DCT_v_scaled_size)
 - * sample rows of each component.  Upsampling will normally produce
 - * max_v_samp_factor pixel rows from each row group (but this could vary
 - * if the upsampler is applying a scale factor of its own).
 - *
 - * An excellent reference for image resampling is
 - *   Digital Image Warping, George Wolberg, 1990.
 - *   Pub. by IEEE Computer Society Press, Los Alamitos, CA. ISBN 0-8186-8944-7.
 - */
 -
 -#define JPEG_INTERNALS
 -#include "jinclude.h"
 -#include "jpeglib.h"
 -
 -
 -/* Pointer to routine to upsample a single component */
 -typedef JMETHOD(void, upsample1_ptr,
 -		(j_decompress_ptr cinfo, jpeg_component_info * compptr,
 -		 JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr));
 -
 -/* Private subobject */
 -
 -typedef struct {
 -  struct jpeg_upsampler pub;	/* public fields */
 -
 -  /* Color conversion buffer.  When using separate upsampling and color
 -   * conversion steps, this buffer holds one upsampled row group until it
 -   * has been color converted and output.
 -   * Note: we do not allocate any storage for component(s) which are full-size,
 -   * ie do not need rescaling.  The corresponding entry of color_buf[] is
 -   * simply set to point to the input data array, thereby avoiding copying.
 -   */
 -  JSAMPARRAY color_buf[MAX_COMPONENTS];
 -
 -  /* Per-component upsampling method pointers */
 -  upsample1_ptr methods[MAX_COMPONENTS];
 -
 -  int next_row_out;		/* counts rows emitted from color_buf */
 -  JDIMENSION rows_to_go;	/* counts rows remaining in image */
 -
 -  /* Height of an input row group for each component. */
 -  int rowgroup_height[MAX_COMPONENTS];
 -
 -  /* These arrays save pixel expansion factors so that int_expand need not
 -   * recompute them each time.  They are unused for other upsampling methods.
 -   */
 -  UINT8 h_expand[MAX_COMPONENTS];
 -  UINT8 v_expand[MAX_COMPONENTS];
 -} my_upsampler;
 -
 -typedef my_upsampler * my_upsample_ptr;
 -
 -
 -/*
 - * Initialize for an upsampling pass.
 - */
 -
 -METHODDEF(void)
 -start_pass_upsample (j_decompress_ptr cinfo)
 -{
 -  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
 -
 -  /* Mark the conversion buffer empty */
 -  upsample->next_row_out = cinfo->max_v_samp_factor;
 -  /* Initialize total-height counter for detecting bottom of image */
 -  upsample->rows_to_go = cinfo->output_height;
 -}
 -
 -
 -/*
 - * Control routine to do upsampling (and color conversion).
 - *
 - * In this version we upsample each component independently.
 - * We upsample one row group into the conversion buffer, then apply
 - * color conversion a row at a time.
 - */
 -
 -METHODDEF(void)
 -sep_upsample (j_decompress_ptr cinfo,
 -	      JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,
 -	      JDIMENSION in_row_groups_avail,
 -	      JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
 -	      JDIMENSION out_rows_avail)
 -{
 -  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
 -  int ci;
 -  jpeg_component_info * compptr;
 -  JDIMENSION num_rows;
 -
 -  /* Fill the conversion buffer, if it's empty */
 -  if (upsample->next_row_out >= cinfo->max_v_samp_factor) {
 -    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
 -	 ci++, compptr++) {
 -      /* Invoke per-component upsample method.  Notice we pass a POINTER
 -       * to color_buf[ci], so that fullsize_upsample can change it.
 -       */
 -      (*upsample->methods[ci]) (cinfo, compptr,
 -	input_buf[ci] + (*in_row_group_ctr * upsample->rowgroup_height[ci]),
 -	upsample->color_buf + ci);
 -    }
 -    upsample->next_row_out = 0;
 -  }
 -
 -  /* Color-convert and emit rows */
 -
 -  /* How many we have in the buffer: */
 -  num_rows = (JDIMENSION) (cinfo->max_v_samp_factor - upsample->next_row_out);
 -  /* Not more than the distance to the end of the image.  Need this test
 -   * in case the image height is not a multiple of max_v_samp_factor:
 -   */
 -  if (num_rows > upsample->rows_to_go) 
 -    num_rows = upsample->rows_to_go;
 -  /* And not more than what the client can accept: */
 -  out_rows_avail -= *out_row_ctr;
 -  if (num_rows > out_rows_avail)
 -    num_rows = out_rows_avail;
 -
 -  (*cinfo->cconvert->color_convert) (cinfo, upsample->color_buf,
 -				     (JDIMENSION) upsample->next_row_out,
 -				     output_buf + *out_row_ctr,
 -				     (int) num_rows);
 -
 -  /* Adjust counts */
 -  *out_row_ctr += num_rows;
 -  upsample->rows_to_go -= num_rows;
 -  upsample->next_row_out += num_rows;
 -  /* When the buffer is emptied, declare this input row group consumed */
 -  if (upsample->next_row_out >= cinfo->max_v_samp_factor)
 -    (*in_row_group_ctr)++;
 -}
 -
 -
 -/*
 - * These are the routines invoked by sep_upsample to upsample pixel values
 - * of a single component.  One row group is processed per call.
 - */
 -
 -
 -/*
 - * For full-size components, we just make color_buf[ci] point at the
 - * input buffer, and thus avoid copying any data.  Note that this is
 - * safe only because sep_upsample doesn't declare the input row group
 - * "consumed" until we are done color converting and emitting it.
 - */
 -
 -METHODDEF(void)
 -fullsize_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,
 -		   JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)
 -{
 -  *output_data_ptr = input_data;
 -}
 -
 -
 -/*
 - * This is a no-op version used for "uninteresting" components.
 - * These components will not be referenced by color conversion.
 - */
 -
 -METHODDEF(void)
 -noop_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,
 -	       JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)
 -{
 -  *output_data_ptr = NULL;	/* safety check */
 -}
 -
 -
 -/*
 - * This version handles any integral sampling ratios.
 - * This is not used for typical JPEG files, so it need not be fast.
 - * Nor, for that matter, is it particularly accurate: the algorithm is
 - * simple replication of the input pixel onto the corresponding output
 - * pixels.  The hi-falutin sampling literature refers to this as a
 - * "box filter".  A box filter tends to introduce visible artifacts,
 - * so if you are actually going to use 3:1 or 4:1 sampling ratios
 - * you would be well advised to improve this code.
 - */
 -
 -METHODDEF(void)
 -int_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,
 -	      JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)
 -{
 -  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;
 -  JSAMPARRAY output_data = *output_data_ptr;
 -  register JSAMPROW inptr, outptr;
 -  register JSAMPLE invalue;
 -  register int h;
 -  JSAMPROW outend;
 -  int h_expand, v_expand;
 -  int inrow, outrow;
 -
 -  h_expand = upsample->h_expand[compptr->component_index];
 -  v_expand = upsample->v_expand[compptr->component_index];
 -
 -  inrow = outrow = 0;
 -  while (outrow < cinfo->max_v_samp_factor) {
 -    /* Generate one output row with proper horizontal expansion */
 -    inptr = input_data[inrow];
 -    outptr = output_data[outrow];
 -    outend = outptr + cinfo->output_width;
 -    while (outptr < outend) {
 -      invalue = *inptr++;	/* don't need GETJSAMPLE() here */
 -      for (h = h_expand; h > 0; h--) {
 -	*outptr++ = invalue;
 -      }
 -    }
 -    /* Generate any additional output rows by duplicating the first one */
 -    if (v_expand > 1) {
 -      jcopy_sample_rows(output_data, outrow, output_data, outrow+1,
 -			v_expand-1, cinfo->output_width);
 -    }
 -    inrow++;
 -    outrow += v_expand;
 -  }
 -}
 -
 -
 -/*
 - * Fast processing for the common case of 2:1 horizontal and 1:1 vertical.
 - * It's still a box filter.
 - */
 -
 -METHODDEF(void)
 -h2v1_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,
 -	       JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)
 -{
 -  JSAMPARRAY output_data = *output_data_ptr;
 -  register JSAMPROW inptr, outptr;
 -  register JSAMPLE invalue;
 -  JSAMPROW outend;
 -  int outrow;
 -
 -  for (outrow = 0; outrow < cinfo->max_v_samp_factor; outrow++) {
 -    inptr = input_data[outrow];
 -    outptr = output_data[outrow];
 -    outend = outptr + cinfo->output_width;
 -    while (outptr < outend) {
 -      invalue = *inptr++;	/* don't need GETJSAMPLE() here */
 -      *outptr++ = invalue;
 -      *outptr++ = invalue;
 -    }
 -  }
 -}
 -
 -
 -/*
 - * Fast processing for the common case of 2:1 horizontal and 2:1 vertical.
 - * It's still a box filter.
 - */
 -
 -METHODDEF(void)
 -h2v2_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,
 -	       JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)
 -{
 -  JSAMPARRAY output_data = *output_data_ptr;
 -  register JSAMPROW inptr, outptr;
 -  register JSAMPLE invalue;
 -  JSAMPROW outend;
 -  int inrow, outrow;
 -
 -  inrow = outrow = 0;
 -  while (outrow < cinfo->max_v_samp_factor) {
 -    inptr = input_data[inrow];
 -    outptr = output_data[outrow];
 -    outend = outptr + cinfo->output_width;
 -    while (outptr < outend) {
 -      invalue = *inptr++;	/* don't need GETJSAMPLE() here */
 -      *outptr++ = invalue;
 -      *outptr++ = invalue;
 -    }
 -    jcopy_sample_rows(output_data, outrow, output_data, outrow+1,
 -		      1, cinfo->output_width);
 -    inrow++;
 -    outrow += 2;
 -  }
 -}
 -
 -
 -/*
 - * Module initialization routine for upsampling.
 - */
 -
 -GLOBAL(void)
 -jinit_upsampler (j_decompress_ptr cinfo)
 -{
 -  my_upsample_ptr upsample;
 -  int ci;
 -  jpeg_component_info * compptr;
 -  boolean need_buffer;
 -  int h_in_group, v_in_group, h_out_group, v_out_group;
 -
 -  upsample = (my_upsample_ptr)
 -    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
 -				SIZEOF(my_upsampler));
 -  cinfo->upsample = (struct jpeg_upsampler *) upsample;
 -  upsample->pub.start_pass = start_pass_upsample;
 -  upsample->pub.upsample = sep_upsample;
 -  upsample->pub.need_context_rows = FALSE; /* until we find out differently */
 -
 -  if (cinfo->CCIR601_sampling)	/* this isn't supported */
 -    ERREXIT(cinfo, JERR_CCIR601_NOTIMPL);
 -
 -  /* Verify we can handle the sampling factors, select per-component methods,
 -   * and create storage as needed.
 -   */
 -  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
 -       ci++, compptr++) {
 -    /* Compute size of an "input group" after IDCT scaling.  This many samples
 -     * are to be converted to max_h_samp_factor * max_v_samp_factor pixels.
 -     */
 -    h_in_group = (compptr->h_samp_factor * compptr->DCT_h_scaled_size) /
 -		 cinfo->min_DCT_h_scaled_size;
 -    v_in_group = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) /
 -		 cinfo->min_DCT_v_scaled_size;
 -    h_out_group = cinfo->max_h_samp_factor;
 -    v_out_group = cinfo->max_v_samp_factor;
 -    upsample->rowgroup_height[ci] = v_in_group; /* save for use later */
 -    need_buffer = TRUE;
 -    if (! compptr->component_needed) {
 -      /* Don't bother to upsample an uninteresting component. */
 -      upsample->methods[ci] = noop_upsample;
 -      need_buffer = FALSE;
 -    } else if (h_in_group == h_out_group && v_in_group == v_out_group) {
 -      /* Fullsize components can be processed without any work. */
 -      upsample->methods[ci] = fullsize_upsample;
 -      need_buffer = FALSE;
 -    } else if (h_in_group * 2 == h_out_group &&
 -	       v_in_group == v_out_group) {
 -      /* Special case for 2h1v upsampling */
 -      upsample->methods[ci] = h2v1_upsample;
 -    } else if (h_in_group * 2 == h_out_group &&
 -	       v_in_group * 2 == v_out_group) {
 -      /* Special case for 2h2v upsampling */
 -      upsample->methods[ci] = h2v2_upsample;
 -    } else if ((h_out_group % h_in_group) == 0 &&
 -	       (v_out_group % v_in_group) == 0) {
 -      /* Generic integral-factors upsampling method */
 -      upsample->methods[ci] = int_upsample;
 -      upsample->h_expand[ci] = (UINT8) (h_out_group / h_in_group);
 -      upsample->v_expand[ci] = (UINT8) (v_out_group / v_in_group);
 -    } else
 -      ERREXIT(cinfo, JERR_FRACT_SAMPLE_NOTIMPL);
 -    if (need_buffer) {
 -      upsample->color_buf[ci] = (*cinfo->mem->alloc_sarray)
 -	((j_common_ptr) cinfo, JPOOL_IMAGE,
 -	 (JDIMENSION) jround_up((long) cinfo->output_width,
 -				(long) cinfo->max_h_samp_factor),
 -	 (JDIMENSION) cinfo->max_v_samp_factor);
 -    }
 -  }
 -}
 +/* + * jdsample.c + * + * Copyright (C) 1991-1996, Thomas G. Lane. + * Modified 2002-2008 by 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 upsampling routines. + * + * Upsampling input data is counted in "row groups".  A row group + * is defined to be (v_samp_factor * DCT_v_scaled_size / min_DCT_v_scaled_size) + * sample rows of each component.  Upsampling will normally produce + * max_v_samp_factor pixel rows from each row group (but this could vary + * if the upsampler is applying a scale factor of its own). + * + * An excellent reference for image resampling is + *   Digital Image Warping, George Wolberg, 1990. + *   Pub. by IEEE Computer Society Press, Los Alamitos, CA. ISBN 0-8186-8944-7. + */ + +#define JPEG_INTERNALS +#include "jinclude.h" +#include "jpeglib.h" + + +/* Pointer to routine to upsample a single component */ +typedef JMETHOD(void, upsample1_ptr, +		(j_decompress_ptr cinfo, jpeg_component_info * compptr, +		 JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)); + +/* Private subobject */ + +typedef struct { +  struct jpeg_upsampler pub;	/* public fields */ + +  /* Color conversion buffer.  When using separate upsampling and color +   * conversion steps, this buffer holds one upsampled row group until it +   * has been color converted and output. +   * Note: we do not allocate any storage for component(s) which are full-size, +   * ie do not need rescaling.  The corresponding entry of color_buf[] is +   * simply set to point to the input data array, thereby avoiding copying. +   */ +  JSAMPARRAY color_buf[MAX_COMPONENTS]; + +  /* Per-component upsampling method pointers */ +  upsample1_ptr methods[MAX_COMPONENTS]; + +  int next_row_out;		/* counts rows emitted from color_buf */ +  JDIMENSION rows_to_go;	/* counts rows remaining in image */ + +  /* Height of an input row group for each component. */ +  int rowgroup_height[MAX_COMPONENTS]; + +  /* These arrays save pixel expansion factors so that int_expand need not +   * recompute them each time.  They are unused for other upsampling methods. +   */ +  UINT8 h_expand[MAX_COMPONENTS]; +  UINT8 v_expand[MAX_COMPONENTS]; +} my_upsampler; + +typedef my_upsampler * my_upsample_ptr; + + +/* + * Initialize for an upsampling pass. + */ + +METHODDEF(void) +start_pass_upsample (j_decompress_ptr cinfo) +{ +  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; + +  /* Mark the conversion buffer empty */ +  upsample->next_row_out = cinfo->max_v_samp_factor; +  /* Initialize total-height counter for detecting bottom of image */ +  upsample->rows_to_go = cinfo->output_height; +} + + +/* + * Control routine to do upsampling (and color conversion). + * + * In this version we upsample each component independently. + * We upsample one row group into the conversion buffer, then apply + * color conversion a row at a time. + */ + +METHODDEF(void) +sep_upsample (j_decompress_ptr cinfo, +	      JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, +	      JDIMENSION in_row_groups_avail, +	      JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, +	      JDIMENSION out_rows_avail) +{ +  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; +  int ci; +  jpeg_component_info * compptr; +  JDIMENSION num_rows; + +  /* Fill the conversion buffer, if it's empty */ +  if (upsample->next_row_out >= cinfo->max_v_samp_factor) { +    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; +	 ci++, compptr++) { +      /* Invoke per-component upsample method.  Notice we pass a POINTER +       * to color_buf[ci], so that fullsize_upsample can change it. +       */ +      (*upsample->methods[ci]) (cinfo, compptr, +	input_buf[ci] + (*in_row_group_ctr * upsample->rowgroup_height[ci]), +	upsample->color_buf + ci); +    } +    upsample->next_row_out = 0; +  } + +  /* Color-convert and emit rows */ + +  /* How many we have in the buffer: */ +  num_rows = (JDIMENSION) (cinfo->max_v_samp_factor - upsample->next_row_out); +  /* Not more than the distance to the end of the image.  Need this test +   * in case the image height is not a multiple of max_v_samp_factor: +   */ +  if (num_rows > upsample->rows_to_go)  +    num_rows = upsample->rows_to_go; +  /* And not more than what the client can accept: */ +  out_rows_avail -= *out_row_ctr; +  if (num_rows > out_rows_avail) +    num_rows = out_rows_avail; + +  (*cinfo->cconvert->color_convert) (cinfo, upsample->color_buf, +				     (JDIMENSION) upsample->next_row_out, +				     output_buf + *out_row_ctr, +				     (int) num_rows); + +  /* Adjust counts */ +  *out_row_ctr += num_rows; +  upsample->rows_to_go -= num_rows; +  upsample->next_row_out += num_rows; +  /* When the buffer is emptied, declare this input row group consumed */ +  if (upsample->next_row_out >= cinfo->max_v_samp_factor) +    (*in_row_group_ctr)++; +} + + +/* + * These are the routines invoked by sep_upsample to upsample pixel values + * of a single component.  One row group is processed per call. + */ + + +/* + * For full-size components, we just make color_buf[ci] point at the + * input buffer, and thus avoid copying any data.  Note that this is + * safe only because sep_upsample doesn't declare the input row group + * "consumed" until we are done color converting and emitting it. + */ + +METHODDEF(void) +fullsize_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr, +		   JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr) +{ +  *output_data_ptr = input_data; +} + + +/* + * This is a no-op version used for "uninteresting" components. + * These components will not be referenced by color conversion. + */ + +METHODDEF(void) +noop_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr, +	       JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr) +{ +  *output_data_ptr = NULL;	/* safety check */ +} + + +/* + * This version handles any integral sampling ratios. + * This is not used for typical JPEG files, so it need not be fast. + * Nor, for that matter, is it particularly accurate: the algorithm is + * simple replication of the input pixel onto the corresponding output + * pixels.  The hi-falutin sampling literature refers to this as a + * "box filter".  A box filter tends to introduce visible artifacts, + * so if you are actually going to use 3:1 or 4:1 sampling ratios + * you would be well advised to improve this code. + */ + +METHODDEF(void) +int_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr, +	      JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr) +{ +  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample; +  JSAMPARRAY output_data = *output_data_ptr; +  register JSAMPROW inptr, outptr; +  register JSAMPLE invalue; +  register int h; +  JSAMPROW outend; +  int h_expand, v_expand; +  int inrow, outrow; + +  h_expand = upsample->h_expand[compptr->component_index]; +  v_expand = upsample->v_expand[compptr->component_index]; + +  inrow = outrow = 0; +  while (outrow < cinfo->max_v_samp_factor) { +    /* Generate one output row with proper horizontal expansion */ +    inptr = input_data[inrow]; +    outptr = output_data[outrow]; +    outend = outptr + cinfo->output_width; +    while (outptr < outend) { +      invalue = *inptr++;	/* don't need GETJSAMPLE() here */ +      for (h = h_expand; h > 0; h--) { +	*outptr++ = invalue; +      } +    } +    /* Generate any additional output rows by duplicating the first one */ +    if (v_expand > 1) { +      jcopy_sample_rows(output_data, outrow, output_data, outrow+1, +			v_expand-1, cinfo->output_width); +    } +    inrow++; +    outrow += v_expand; +  } +} + + +/* + * Fast processing for the common case of 2:1 horizontal and 1:1 vertical. + * It's still a box filter. + */ + +METHODDEF(void) +h2v1_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr, +	       JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr) +{ +  JSAMPARRAY output_data = *output_data_ptr; +  register JSAMPROW inptr, outptr; +  register JSAMPLE invalue; +  JSAMPROW outend; +  int outrow; + +  for (outrow = 0; outrow < cinfo->max_v_samp_factor; outrow++) { +    inptr = input_data[outrow]; +    outptr = output_data[outrow]; +    outend = outptr + cinfo->output_width; +    while (outptr < outend) { +      invalue = *inptr++;	/* don't need GETJSAMPLE() here */ +      *outptr++ = invalue; +      *outptr++ = invalue; +    } +  } +} + + +/* + * Fast processing for the common case of 2:1 horizontal and 2:1 vertical. + * It's still a box filter. + */ + +METHODDEF(void) +h2v2_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr, +	       JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr) +{ +  JSAMPARRAY output_data = *output_data_ptr; +  register JSAMPROW inptr, outptr; +  register JSAMPLE invalue; +  JSAMPROW outend; +  int inrow, outrow; + +  inrow = outrow = 0; +  while (outrow < cinfo->max_v_samp_factor) { +    inptr = input_data[inrow]; +    outptr = output_data[outrow]; +    outend = outptr + cinfo->output_width; +    while (outptr < outend) { +      invalue = *inptr++;	/* don't need GETJSAMPLE() here */ +      *outptr++ = invalue; +      *outptr++ = invalue; +    } +    jcopy_sample_rows(output_data, outrow, output_data, outrow+1, +		      1, cinfo->output_width); +    inrow++; +    outrow += 2; +  } +} + + +/* + * Module initialization routine for upsampling. + */ + +GLOBAL(void) +jinit_upsampler (j_decompress_ptr cinfo) +{ +  my_upsample_ptr upsample; +  int ci; +  jpeg_component_info * compptr; +  boolean need_buffer; +  int h_in_group, v_in_group, h_out_group, v_out_group; + +  upsample = (my_upsample_ptr) +    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, +				SIZEOF(my_upsampler)); +  cinfo->upsample = (struct jpeg_upsampler *) upsample; +  upsample->pub.start_pass = start_pass_upsample; +  upsample->pub.upsample = sep_upsample; +  upsample->pub.need_context_rows = FALSE; /* until we find out differently */ + +  if (cinfo->CCIR601_sampling)	/* this isn't supported */ +    ERREXIT(cinfo, JERR_CCIR601_NOTIMPL); + +  /* Verify we can handle the sampling factors, select per-component methods, +   * and create storage as needed. +   */ +  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; +       ci++, compptr++) { +    /* Compute size of an "input group" after IDCT scaling.  This many samples +     * are to be converted to max_h_samp_factor * max_v_samp_factor pixels. +     */ +    h_in_group = (compptr->h_samp_factor * compptr->DCT_h_scaled_size) / +		 cinfo->min_DCT_h_scaled_size; +    v_in_group = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) / +		 cinfo->min_DCT_v_scaled_size; +    h_out_group = cinfo->max_h_samp_factor; +    v_out_group = cinfo->max_v_samp_factor; +    upsample->rowgroup_height[ci] = v_in_group; /* save for use later */ +    need_buffer = TRUE; +    if (! compptr->component_needed) { +      /* Don't bother to upsample an uninteresting component. */ +      upsample->methods[ci] = noop_upsample; +      need_buffer = FALSE; +    } else if (h_in_group == h_out_group && v_in_group == v_out_group) { +      /* Fullsize components can be processed without any work. */ +      upsample->methods[ci] = fullsize_upsample; +      need_buffer = FALSE; +    } else if (h_in_group * 2 == h_out_group && +	       v_in_group == v_out_group) { +      /* Special case for 2h1v upsampling */ +      upsample->methods[ci] = h2v1_upsample; +    } else if (h_in_group * 2 == h_out_group && +	       v_in_group * 2 == v_out_group) { +      /* Special case for 2h2v upsampling */ +      upsample->methods[ci] = h2v2_upsample; +    } else if ((h_out_group % h_in_group) == 0 && +	       (v_out_group % v_in_group) == 0) { +      /* Generic integral-factors upsampling method */ +      upsample->methods[ci] = int_upsample; +      upsample->h_expand[ci] = (UINT8) (h_out_group / h_in_group); +      upsample->v_expand[ci] = (UINT8) (v_out_group / v_in_group); +    } else +      ERREXIT(cinfo, JERR_FRACT_SAMPLE_NOTIMPL); +    if (need_buffer) { +      upsample->color_buf[ci] = (*cinfo->mem->alloc_sarray) +	((j_common_ptr) cinfo, JPOOL_IMAGE, +	 (JDIMENSION) jround_up((long) cinfo->output_width, +				(long) cinfo->max_h_samp_factor), +	 (JDIMENSION) cinfo->max_v_samp_factor); +    } +  } +}  | 
