diff options
Diffstat (limited to 'plugins/FreeImage/Source/FreeImageToolkit/ClassicRotate.cpp')
| -rw-r--r-- | plugins/FreeImage/Source/FreeImageToolkit/ClassicRotate.cpp | 956 |
1 files changed, 956 insertions, 0 deletions
diff --git a/plugins/FreeImage/Source/FreeImageToolkit/ClassicRotate.cpp b/plugins/FreeImage/Source/FreeImageToolkit/ClassicRotate.cpp new file mode 100644 index 0000000000..9e5ea7c9c3 --- /dev/null +++ b/plugins/FreeImage/Source/FreeImageToolkit/ClassicRotate.cpp @@ -0,0 +1,956 @@ +// ==========================================================
+// Bitmap rotation by means of 3 shears.
+//
+// Design and implementation by
+// - Hervé Drolon (drolon@infonie.fr)
+// - Thorsten Radde (support@IdealSoftware.com)
+//
+// This file is part of FreeImage 3
+//
+// COVERED CODE IS PROVIDED UNDER THIS LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTY
+// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES
+// THAT THE COVERED CODE IS FREE OF DEFECTS, MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE
+// OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE COVERED
+// CODE IS WITH YOU. SHOULD ANY COVERED CODE PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT
+// THE INITIAL DEVELOPER OR ANY OTHER CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY
+// SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL
+// PART OF THIS LICENSE. NO USE OF ANY COVERED CODE IS AUTHORIZED HEREUNDER EXCEPT UNDER
+// THIS DISCLAIMER.
+//
+// Use at your own risk!
+// ==========================================================
+
+/*
+ ============================================================
+ References :
+ [1] Paeth A., A Fast Algorithm for General Raster Rotation.
+ Graphics Gems, p. 179, Andrew Glassner editor, Academic Press, 1990.
+ [2] Yariv E., High quality image rotation (rotate by shear).
+ [Online] http://www.codeproject.com/bitmap/rotatebyshear.asp
+ [3] Treskunov A., Fast and high quality true-color bitmap rotation function.
+ [Online] http://anton.treskunov.net/Software/doc/fast_and_high_quality_true_color_bitmap_rotation_function.html
+ ============================================================
+*/
+
+#include "FreeImage.h"
+#include "Utilities.h"
+
+#define RBLOCK 64 // image blocks of RBLOCK*RBLOCK pixels
+
+/////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// Prototypes definition
+
+static void HorizontalSkew(FIBITMAP *src, FIBITMAP *dst, int row, int iOffset, double dWeight, const void *bkcolor);
+static void VerticalSkew(FIBITMAP *src, FIBITMAP *dst, int col, int iOffset, double dWeight, const void *bkcolor);
+static FIBITMAP* Rotate90(FIBITMAP *src);
+static FIBITMAP* Rotate180(FIBITMAP *src);
+static FIBITMAP* Rotate270(FIBITMAP *src);
+static FIBITMAP* Rotate45(FIBITMAP *src, double dAngle, const void *bkcolor);
+static FIBITMAP* RotateAny(FIBITMAP *src, double dAngle, const void *bkcolor);
+
+/////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+/**
+Skews a row horizontally (with filtered weights).
+Limited to 45 degree skewing only. Filters two adjacent pixels.
+Parameter T can be BYTE, WORD of float.
+@param src Pointer to source image to rotate
+@param dst Pointer to destination image
+@param row Row index
+@param iOffset Skew offset
+@param dWeight Relative weight of right pixel
+@param bkcolor Background color
+*/
+template <class T> void
+HorizontalSkewT(FIBITMAP *src, FIBITMAP *dst, int row, int iOffset, double weight, const void *bkcolor = NULL) {
+ unsigned i, j;
+ int iXPos;
+
+ unsigned src_width = FreeImage_GetWidth(src);
+ unsigned dst_width = FreeImage_GetWidth(dst);
+
+ T pxlSrc[4], pxlLeft[4], pxlOldLeft[4]; // 4 = 4*sizeof(T) max
+
+ // background
+ const T pxlBlack[4] = {0, 0, 0, 0 };
+ const T *pxlBkg = static_cast<const T*>(bkcolor); // assume at least bytespp and 4*sizeof(T) max
+ if(!pxlBkg) {
+ // default background color is black
+ pxlBkg = pxlBlack;
+ }
+
+ // calculate the number of bytes per pixel
+ unsigned bytespp = FreeImage_GetLine(src) / FreeImage_GetWidth(src);
+ // calculate the number of samples per pixel
+ unsigned samples = bytespp / sizeof(T);
+
+ BYTE *src_bits = FreeImage_GetScanLine(src, row);
+ BYTE *dst_bits = FreeImage_GetScanLine(dst, row);
+
+ // fill gap left of skew with background
+ if(bkcolor) {
+ for(int k = 0; k < iOffset; k++) {
+ memcpy(&dst_bits[k * bytespp], bkcolor, bytespp);
+ }
+ memcpy(&pxlOldLeft[0], bkcolor, bytespp);
+ } else {
+ if(iOffset > 0) {
+ memset(dst_bits, 0, iOffset * bytespp);
+ }
+ memset(&pxlOldLeft[0], 0, bytespp);
+ }
+
+ for(i = 0; i < src_width; i++) {
+ // loop through row pixels
+ memcpy(&pxlSrc[0], src_bits, bytespp);
+ // calculate weights
+ for(j = 0; j < samples; j++) {
+ pxlLeft[j] = static_cast<T>(pxlBkg[j] + (pxlSrc[j] - pxlBkg[j]) * weight + 0.5);
+ }
+ // check boundaries
+ iXPos = i + iOffset;
+ if((iXPos >= 0) && (iXPos < (int)dst_width)) {
+ // update left over on source
+ for(j = 0; j < samples; j++) {
+ pxlSrc[j] = pxlSrc[j] - (pxlLeft[j] - pxlOldLeft[j]);
+ }
+ memcpy(&dst_bits[iXPos*bytespp], &pxlSrc[0], bytespp);
+ }
+ // save leftover for next pixel in scan
+ memcpy(&pxlOldLeft[0], &pxlLeft[0], bytespp);
+
+ // next pixel in scan
+ src_bits += bytespp;
+ }
+
+ // go to rightmost point of skew
+ iXPos = src_width + iOffset;
+
+ if((iXPos >= 0) && (iXPos < (int)dst_width)) {
+ dst_bits = FreeImage_GetScanLine(dst, row) + iXPos * bytespp;
+
+ // If still in image bounds, put leftovers there
+ memcpy(dst_bits, &pxlOldLeft[0], bytespp);
+
+ // clear to the right of the skewed line with background
+ dst_bits += bytespp;
+ if(bkcolor) {
+ for(i = 0; i < dst_width - iXPos - 1; i++) {
+ memcpy(&dst_bits[i * bytespp], bkcolor, bytespp);
+ }
+ } else {
+ memset(dst_bits, 0, bytespp * (dst_width - iXPos - 1));
+ }
+
+ }
+}
+
+/**
+Skews a row horizontally (with filtered weights).
+Limited to 45 degree skewing only. Filters two adjacent pixels.
+@param src Pointer to source image to rotate
+@param dst Pointer to destination image
+@param row Row index
+@param iOffset Skew offset
+@param dWeight Relative weight of right pixel
+@param bkcolor Background color
+*/
+static void
+HorizontalSkew(FIBITMAP *src, FIBITMAP *dst, int row, int iOffset, double dWeight, const void *bkcolor) {
+ FREE_IMAGE_TYPE image_type = FreeImage_GetImageType(src);
+
+ switch(image_type) {
+ case FIT_BITMAP:
+ switch(FreeImage_GetBPP(src)) {
+ case 8:
+ case 24:
+ case 32:
+ HorizontalSkewT<BYTE>(src, dst, row, iOffset, dWeight, bkcolor);
+ break;
+ }
+ break;
+ case FIT_UINT16:
+ case FIT_RGB16:
+ case FIT_RGBA16:
+ HorizontalSkewT<WORD>(src, dst, row, iOffset, dWeight, bkcolor);
+ break;
+ case FIT_FLOAT:
+ case FIT_RGBF:
+ case FIT_RGBAF:
+ HorizontalSkewT<float>(src, dst, row, iOffset, dWeight, bkcolor);
+ break;
+ }
+}
+
+/**
+Skews a column vertically (with filtered weights).
+Limited to 45 degree skewing only. Filters two adjacent pixels.
+Parameter T can be BYTE, WORD of float.
+@param src Pointer to source image to rotate
+@param dst Pointer to destination image
+@param col Column index
+@param iOffset Skew offset
+@param dWeight Relative weight of upper pixel
+@param bkcolor Background color
+*/
+template <class T> void
+VerticalSkewT(FIBITMAP *src, FIBITMAP *dst, int col, int iOffset, double weight, const void *bkcolor = NULL) {
+ unsigned i, j;
+ int iYPos;
+
+ unsigned src_height = FreeImage_GetHeight(src);
+ unsigned dst_height = FreeImage_GetHeight(dst);
+
+ T pxlSrc[4], pxlLeft[4], pxlOldLeft[4]; // 4 = 4*sizeof(T) max
+
+ // background
+ const T pxlBlack[4] = {0, 0, 0, 0 };
+ const T *pxlBkg = static_cast<const T*>(bkcolor); // assume at least bytespp and 4*sizeof(T) max
+ if(!pxlBkg) {
+ // default background color is black
+ pxlBkg = pxlBlack;
+ }
+
+ // calculate the number of bytes per pixel
+ unsigned bytespp = FreeImage_GetLine(src) / FreeImage_GetWidth(src);
+ // calculate the number of samples per pixel
+ unsigned samples = bytespp / sizeof(T);
+
+ unsigned src_pitch = FreeImage_GetPitch(src);
+ unsigned dst_pitch = FreeImage_GetPitch(dst);
+ unsigned index = col * bytespp;
+
+ BYTE *src_bits = FreeImage_GetBits(src) + index;
+ BYTE *dst_bits = FreeImage_GetBits(dst) + index;
+
+ // fill gap above skew with background
+ if(bkcolor) {
+ for(int k = 0; k < iOffset; k++) {
+ memcpy(dst_bits, bkcolor, bytespp);
+ dst_bits += dst_pitch;
+ }
+ memcpy(&pxlOldLeft[0], bkcolor, bytespp);
+ } else {
+ for(int k = 0; k < iOffset; k++) {
+ memset(dst_bits, 0, bytespp);
+ dst_bits += dst_pitch;
+ }
+ memset(&pxlOldLeft[0], 0, bytespp);
+ }
+
+ for(i = 0; i < src_height; i++) {
+ // loop through column pixels
+ memcpy(&pxlSrc[0], src_bits, bytespp);
+ // calculate weights
+ for(j = 0; j < samples; j++) {
+ pxlLeft[j] = static_cast<T>(pxlBkg[j] + (pxlSrc[j] - pxlBkg[j]) * weight + 0.5);
+ }
+ // check boundaries
+ iYPos = i + iOffset;
+ if((iYPos >= 0) && (iYPos < (int)dst_height)) {
+ // update left over on source
+ for(j = 0; j < samples; j++) {
+ pxlSrc[j] = pxlSrc[j] - (pxlLeft[j] - pxlOldLeft[j]);
+ }
+ dst_bits = FreeImage_GetScanLine(dst, iYPos) + index;
+ memcpy(dst_bits, &pxlSrc[0], bytespp);
+ }
+ // save leftover for next pixel in scan
+ memcpy(&pxlOldLeft[0], &pxlLeft[0], bytespp);
+
+ // next pixel in scan
+ src_bits += src_pitch;
+ }
+ // go to bottom point of skew
+ iYPos = src_height + iOffset;
+
+ if((iYPos >= 0) && (iYPos < (int)dst_height)) {
+ dst_bits = FreeImage_GetScanLine(dst, iYPos) + index;
+
+ // if still in image bounds, put leftovers there
+ memcpy(dst_bits, &pxlOldLeft[0], bytespp);
+
+ // clear below skewed line with background
+ if(bkcolor) {
+ while(++iYPos < (int)dst_height) {
+ dst_bits += dst_pitch;
+ memcpy(dst_bits, bkcolor, bytespp);
+ }
+ } else {
+ while(++iYPos < (int)dst_height) {
+ dst_bits += dst_pitch;
+ memset(dst_bits, 0, bytespp);
+ }
+ }
+ }
+}
+
+/**
+Skews a column vertically (with filtered weights).
+Limited to 45 degree skewing only. Filters two adjacent pixels.
+@param src Pointer to source image to rotate
+@param dst Pointer to destination image
+@param col Column index
+@param iOffset Skew offset
+@param dWeight Relative weight of upper pixel
+@param bkcolor Background color
+*/
+static void
+VerticalSkew(FIBITMAP *src, FIBITMAP *dst, int col, int iOffset, double dWeight, const void *bkcolor) {
+ FREE_IMAGE_TYPE image_type = FreeImage_GetImageType(src);
+
+ switch(image_type) {
+ case FIT_BITMAP:
+ switch(FreeImage_GetBPP(src)) {
+ case 8:
+ case 24:
+ case 32:
+ VerticalSkewT<BYTE>(src, dst, col, iOffset, dWeight, bkcolor);
+ break;
+ }
+ break;
+ case FIT_UINT16:
+ case FIT_RGB16:
+ case FIT_RGBA16:
+ VerticalSkewT<WORD>(src, dst, col, iOffset, dWeight, bkcolor);
+ break;
+ case FIT_FLOAT:
+ case FIT_RGBF:
+ case FIT_RGBAF:
+ VerticalSkewT<float>(src, dst, col, iOffset, dWeight, bkcolor);
+ break;
+ }
+}
+
+/**
+Rotates an image by 90 degrees (counter clockwise).
+Precise rotation, no filters required.<br>
+Code adapted from CxImage (http://www.xdp.it/cximage.htm)
+@param src Pointer to source image to rotate
+@return Returns a pointer to a newly allocated rotated image if successful, returns NULL otherwise
+*/
+static FIBITMAP*
+Rotate90(FIBITMAP *src) {
+ int x, y, y2;
+
+ int bpp = FreeImage_GetBPP(src);
+
+ int src_width = FreeImage_GetWidth(src);
+ int src_height = FreeImage_GetHeight(src);
+ int dst_width = src_height;
+ int dst_height = src_width;
+
+ FREE_IMAGE_TYPE image_type = FreeImage_GetImageType(src);
+
+ // allocate and clear dst image
+ FIBITMAP *dst = FreeImage_AllocateT(image_type, dst_width, dst_height, bpp);
+ if(NULL == dst) return NULL;
+
+ // get src and dst scan width
+ int src_pitch = FreeImage_GetPitch(src);
+ int dst_pitch = FreeImage_GetPitch(dst);
+
+ switch(image_type) {
+ case FIT_BITMAP:
+ if(bpp == 1) {
+ // speedy rotate for BW images
+
+ BYTE *sbits, *dbits, *dbitsmax, bitpos, *nrow, *srcdisp;
+ div_t div_r;
+
+ BYTE *bsrc = FreeImage_GetBits(src);
+ BYTE *bdest = FreeImage_GetBits(dst);
+ dbitsmax = bdest + dst_height * dst_pitch - 1;
+
+ for(y = 0; y < src_height; y++) {
+ // figure out the column we are going to be copying to
+ div_r = div(y, 8);
+ // set bit pos of src column byte
+ bitpos = (BYTE)(128 >> div_r.rem);
+ srcdisp = bsrc + y * src_pitch;
+ for (x = 0; x < src_pitch; x++) {
+ // get source bits
+ sbits = srcdisp + x;
+ // get destination column
+ nrow = bdest + (dst_height - 1 - (x * 8)) * dst_pitch + div_r.quot;
+ for (int z = 0; z < 8; z++) {
+ // get destination byte
+ dbits = nrow - z * dst_pitch;
+ if ((dbits < bdest) || (dbits > dbitsmax)) break;
+ if (*sbits & (128 >> z)) *dbits |= bitpos;
+ }
+ }
+ }
+ }
+ else if((bpp == 8) || (bpp == 24) || (bpp == 32)) {
+ // anything other than BW :
+ // This optimized version of rotation rotates image by smaller blocks. It is quite
+ // a bit faster than obvious algorithm, because it produces much less CPU cache misses.
+ // This optimization can be tuned by changing block size (RBLOCK). 96 is good value for current
+ // CPUs (tested on Athlon XP and Celeron D). Larger value (if CPU has enough cache) will increase
+ // speed somehow, but once you drop out of CPU's cache, things will slow down drastically.
+ // For older CPUs with less cache, lower value would yield better results.
+
+ int xs, ys; // x-segment and y-segment
+ BYTE *bsrc = FreeImage_GetBits(src); // source pixels
+ BYTE *bdest = FreeImage_GetBits(dst); // destination pixels
+
+ // calculate the number of bytes per pixel (1 for 8-bit, 3 for 24-bit or 4 for 32-bit)
+ int bytespp = FreeImage_GetLine(src) / FreeImage_GetWidth(src);
+
+ for(xs = 0; xs < dst_width; xs += RBLOCK) { // for all image blocks of RBLOCK*RBLOCK pixels
+ for(ys = 0; ys < dst_height; ys += RBLOCK) {
+ for(y = ys; y < MIN(dst_height, ys + RBLOCK); y++) { // do rotation
+ y2 = dst_height - y - 1;
+ // point to src pixel at (y2, xs)
+ BYTE *src_bits = bsrc + (xs * src_pitch) + (y2 * bytespp);
+ // point to dst pixel at (xs, y)
+ BYTE *dst_bits = bdest + (y * dst_pitch) + (xs * bytespp);
+ for (x = xs; x < MIN(dst_width, xs + RBLOCK); x++) {
+ // dst.SetPixel(x, y, src.GetPixel(y2, x));
+ for(int j = 0; j < bytespp; j++) {
+ dst_bits[j] = src_bits[j];
+ }
+ dst_bits += bytespp;
+ src_bits += src_pitch;
+ }
+ }
+ }
+ }
+ }
+ break;
+ case FIT_UINT16:
+ case FIT_RGB16:
+ case FIT_RGBA16:
+ case FIT_FLOAT:
+ case FIT_RGBF:
+ case FIT_RGBAF:
+ {
+ BYTE *bsrc = FreeImage_GetBits(src); // source pixels
+ BYTE *bdest = FreeImage_GetBits(dst); // destination pixels
+
+ // calculate the number of bytes per pixel
+ int bytespp = FreeImage_GetLine(src) / FreeImage_GetWidth(src);
+
+ for(y = 0; y < dst_height; y++) {
+ BYTE *src_bits = bsrc + (src_width - 1 - y) * bytespp;
+ BYTE *dst_bits = bdest + (y * dst_pitch);
+ for(x = 0; x < dst_width; x++) {
+ for(int j = 0; j < bytespp; j++) {
+ dst_bits[j] = src_bits[j];
+ }
+ src_bits += src_pitch;
+ dst_bits += bytespp;
+ }
+ }
+ }
+ break;
+ }
+
+ return dst;
+}
+
+/**
+Rotates an image by 180 degrees (counter clockwise).
+Precise rotation, no filters required.
+@param src Pointer to source image to rotate
+@return Returns a pointer to a newly allocated rotated image if successful, returns NULL otherwise
+*/
+static FIBITMAP*
+Rotate180(FIBITMAP *src) {
+ int x, y, k, pos;
+
+ int bpp = FreeImage_GetBPP(src);
+
+ int src_width = FreeImage_GetWidth(src);
+ int src_height = FreeImage_GetHeight(src);
+ int dst_width = src_width;
+ int dst_height = src_height;
+
+ FREE_IMAGE_TYPE image_type = FreeImage_GetImageType(src);
+
+ FIBITMAP *dst = FreeImage_AllocateT(image_type, dst_width, dst_height, bpp);
+ if(NULL == dst) return NULL;
+
+ switch(image_type) {
+ case FIT_BITMAP:
+ if(bpp == 1) {
+ for(int y = 0; y < src_height; y++) {
+ BYTE *src_bits = FreeImage_GetScanLine(src, y);
+ BYTE *dst_bits = FreeImage_GetScanLine(dst, dst_height - y - 1);
+ for(int x = 0; x < src_width; x++) {
+ // get bit at (x, y)
+ k = (src_bits[x >> 3] & (0x80 >> (x & 0x07))) != 0;
+ // set bit at (dst_width - x - 1, dst_height - y - 1)
+ pos = dst_width - x - 1;
+ k ? dst_bits[pos >> 3] |= (0x80 >> (pos & 0x7)) : dst_bits[pos >> 3] &= (0xFF7F >> (pos & 0x7));
+ }
+ }
+ }
+ else if((bpp == 8) || (bpp == 24) || (bpp == 32)) {
+ // Calculate the number of bytes per pixel (1 for 8-bit, 3 for 24-bit or 4 for 32-bit)
+ int bytespp = FreeImage_GetLine(src) / FreeImage_GetWidth(src);
+
+ for(y = 0; y < src_height; y++) {
+ BYTE *src_bits = FreeImage_GetScanLine(src, y);
+ BYTE *dst_bits = FreeImage_GetScanLine(dst, dst_height - y - 1) + (dst_width - 1) * bytespp;
+ for(x = 0; x < src_width; x++) {
+ // get pixel at (x, y)
+ // set pixel at (dst_width - x - 1, dst_height - y - 1)
+ for(k = 0; k < bytespp; k++) {
+ dst_bits[k] = src_bits[k];
+ }
+ src_bits += bytespp;
+ dst_bits -= bytespp;
+ }
+ }
+ }
+ break;
+ case FIT_UINT16:
+ case FIT_RGB16:
+ case FIT_RGBA16:
+ case FIT_FLOAT:
+ case FIT_RGBF:
+ case FIT_RGBAF:
+ {
+ // Calculate the number of bytes per pixel
+ int bytespp = FreeImage_GetLine(src) / FreeImage_GetWidth(src);
+
+ for(y = 0; y < src_height; y++) {
+ BYTE *src_bits = FreeImage_GetScanLine(src, y);
+ BYTE *dst_bits = FreeImage_GetScanLine(dst, dst_height - y - 1) + (dst_width - 1) * bytespp;
+ for(x = 0; x < src_width; x++) {
+ // get pixel at (x, y)
+ // set pixel at (dst_width - x - 1, dst_height - y - 1)
+ for(k = 0; k < bytespp; k++) {
+ dst_bits[k] = src_bits[k];
+ }
+ src_bits += bytespp;
+ dst_bits -= bytespp;
+ }
+ }
+ }
+ break;
+ }
+
+ return dst;
+}
+
+/**
+Rotates an image by 270 degrees (counter clockwise).
+Precise rotation, no filters required.<br>
+Code adapted from CxImage (http://www.xdp.it/cximage.htm)
+@param src Pointer to source image to rotate
+@return Returns a pointer to a newly allocated rotated image if successful, returns NULL otherwise
+*/
+static FIBITMAP*
+Rotate270(FIBITMAP *src) {
+ int x, x2, y, dlineup;
+
+ int bpp = FreeImage_GetBPP(src);
+
+ int src_width = FreeImage_GetWidth(src);
+ int src_height = FreeImage_GetHeight(src);
+ int dst_width = src_height;
+ int dst_height = src_width;
+
+ FREE_IMAGE_TYPE image_type = FreeImage_GetImageType(src);
+
+ // allocate and clear dst image
+ FIBITMAP *dst = FreeImage_AllocateT(image_type, dst_width, dst_height, bpp);
+ if(NULL == dst) return NULL;
+
+ // get src and dst scan width
+ int src_pitch = FreeImage_GetPitch(src);
+ int dst_pitch = FreeImage_GetPitch(dst);
+
+ switch(image_type) {
+ case FIT_BITMAP:
+ if(bpp == 1) {
+ // speedy rotate for BW images
+
+ BYTE *sbits, *dbits, *dbitsmax, bitpos, *nrow, *srcdisp;
+ div_t div_r;
+
+ BYTE *bsrc = FreeImage_GetBits(src);
+ BYTE *bdest = FreeImage_GetBits(dst);
+ dbitsmax = bdest + dst_height * dst_pitch - 1;
+ dlineup = 8 * dst_pitch - dst_width;
+
+ for(y = 0; y < src_height; y++) {
+ // figure out the column we are going to be copying to
+ div_r = div(y + dlineup, 8);
+ // set bit pos of src column byte
+ bitpos = (BYTE)(1 << div_r.rem);
+ srcdisp = bsrc + y * src_pitch;
+ for (x = 0; x < src_pitch; x++) {
+ // get source bits
+ sbits = srcdisp + x;
+ // get destination column
+ nrow = bdest + (x * 8) * dst_pitch + dst_pitch - 1 - div_r.quot;
+ for (int z = 0; z < 8; z++) {
+ // get destination byte
+ dbits = nrow + z * dst_pitch;
+ if ((dbits < bdest) || (dbits > dbitsmax)) break;
+ if (*sbits & (128 >> z)) *dbits |= bitpos;
+ }
+ }
+ }
+ }
+ else if((bpp == 8) || (bpp == 24) || (bpp == 32)) {
+ // anything other than BW :
+ // This optimized version of rotation rotates image by smaller blocks. It is quite
+ // a bit faster than obvious algorithm, because it produces much less CPU cache misses.
+ // This optimization can be tuned by changing block size (RBLOCK). 96 is good value for current
+ // CPUs (tested on Athlon XP and Celeron D). Larger value (if CPU has enough cache) will increase
+ // speed somehow, but once you drop out of CPU's cache, things will slow down drastically.
+ // For older CPUs with less cache, lower value would yield better results.
+
+ int xs, ys; // x-segment and y-segment
+ BYTE *bsrc = FreeImage_GetBits(src); // source pixels
+ BYTE *bdest = FreeImage_GetBits(dst); // destination pixels
+
+ // Calculate the number of bytes per pixel (1 for 8-bit, 3 for 24-bit or 4 for 32-bit)
+ int bytespp = FreeImage_GetLine(src) / FreeImage_GetWidth(src);
+
+ for(xs = 0; xs < dst_width; xs += RBLOCK) { // for all image blocks of RBLOCK*RBLOCK pixels
+ for(ys = 0; ys < dst_height; ys += RBLOCK) {
+ for(x = xs; x < MIN(dst_width, xs + RBLOCK); x++) { // do rotation
+ x2 = dst_width - x - 1;
+ // point to src pixel at (ys, x2)
+ BYTE *src_bits = bsrc + (x2 * src_pitch) + (ys * bytespp);
+ // point to dst pixel at (x, ys)
+ BYTE *dst_bits = bdest + (ys * dst_pitch) + (x * bytespp);
+ for (y = ys; y < MIN(dst_height, ys + RBLOCK); y++) {
+ // dst.SetPixel(x, y, src.GetPixel(y, x2));
+ for(int j = 0; j < bytespp; j++) {
+ dst_bits[j] = src_bits[j];
+ }
+ src_bits += bytespp;
+ dst_bits += dst_pitch;
+ }
+ }
+ }
+ }
+ }
+ break;
+ case FIT_UINT16:
+ case FIT_RGB16:
+ case FIT_RGBA16:
+ case FIT_FLOAT:
+ case FIT_RGBF:
+ case FIT_RGBAF:
+ {
+ BYTE *bsrc = FreeImage_GetBits(src); // source pixels
+ BYTE *bdest = FreeImage_GetBits(dst); // destination pixels
+
+ // calculate the number of bytes per pixel
+ int bytespp = FreeImage_GetLine(src) / FreeImage_GetWidth(src);
+
+ for(y = 0; y < dst_height; y++) {
+ BYTE *src_bits = bsrc + (src_height - 1) * src_pitch + y * bytespp;
+ BYTE *dst_bits = bdest + (y * dst_pitch);
+ for(x = 0; x < dst_width; x++) {
+ for(int j = 0; j < bytespp; j++) {
+ dst_bits[j] = src_bits[j];
+ }
+ src_bits -= src_pitch;
+ dst_bits += bytespp;
+ }
+ }
+ }
+ break;
+ }
+
+ return dst;
+}
+
+/**
+Rotates an image by a given degree in range [-45 .. +45] (counter clockwise)
+using the 3-shear technique.
+@param src Pointer to source image to rotate
+@param dAngle Rotation angle
+@return Returns a pointer to a newly allocated rotated image if successful, returns NULL otherwise
+*/
+static FIBITMAP*
+Rotate45(FIBITMAP *src, double dAngle, const void *bkcolor) {
+ const double ROTATE_PI = double(3.1415926535897932384626433832795);
+
+ unsigned u;
+
+ unsigned bpp = FreeImage_GetBPP(src);
+
+ double dRadAngle = dAngle * ROTATE_PI / double(180); // Angle in radians
+ double dSinE = sin(dRadAngle);
+ double dTan = tan(dRadAngle / 2);
+
+ unsigned src_width = FreeImage_GetWidth(src);
+ unsigned src_height = FreeImage_GetHeight(src);
+
+ FREE_IMAGE_TYPE image_type = FreeImage_GetImageType(src);
+
+ // Calc first shear (horizontal) destination image dimensions
+ unsigned width_1 = src_width + unsigned((double)src_height * fabs(dTan) + 0.5);
+ unsigned height_1 = src_height;
+
+ // Perform 1st shear (horizontal)
+ // ----------------------------------------------------------------------
+
+ // Allocate image for 1st shear
+ FIBITMAP *dst1 = FreeImage_AllocateT(image_type, width_1, height_1, bpp);
+ if(NULL == dst1) {
+ return NULL;
+ }
+
+ for(u = 0; u < height_1; u++) {
+ double dShear;
+
+ if(dTan >= 0) {
+ // Positive angle
+ dShear = (u + 0.5) * dTan;
+ }
+ else {
+ // Negative angle
+ dShear = (double(u) - height_1 + 0.5) * dTan;
+ }
+ int iShear = int(floor(dShear));
+ HorizontalSkew(src, dst1, u, iShear, dShear - double(iShear), bkcolor);
+ }
+
+ // Perform 2nd shear (vertical)
+ // ----------------------------------------------------------------------
+
+ // Calc 2nd shear (vertical) destination image dimensions
+ unsigned width_2 = width_1;
+ unsigned height_2 = unsigned((double)src_width * fabs(dSinE) + (double)src_height * cos(dRadAngle) + 0.5) + 1;
+
+ // Allocate image for 2nd shear
+ FIBITMAP *dst2 = FreeImage_AllocateT(image_type, width_2, height_2, bpp);
+ if(NULL == dst2) {
+ FreeImage_Unload(dst1);
+ return NULL;
+ }
+
+ double dOffset; // Variable skew offset
+ if(dSinE > 0) {
+ // Positive angle
+ dOffset = (src_width - 1.0) * dSinE;
+ }
+ else {
+ // Negative angle
+ dOffset = -dSinE * (double(src_width) - width_2);
+ }
+
+ for(u = 0; u < width_2; u++, dOffset -= dSinE) {
+ int iShear = int(floor(dOffset));
+ VerticalSkew(dst1, dst2, u, iShear, dOffset - double(iShear), bkcolor);
+ }
+
+ // Perform 3rd shear (horizontal)
+ // ----------------------------------------------------------------------
+
+ // Free result of 1st shear
+ FreeImage_Unload(dst1);
+
+ // Calc 3rd shear (horizontal) destination image dimensions
+ unsigned width_3 = unsigned(double(src_height) * fabs(dSinE) + double(src_width) * cos(dRadAngle) + 0.5) + 1;
+ unsigned height_3 = height_2;
+
+ // Allocate image for 3rd shear
+ FIBITMAP *dst3 = FreeImage_AllocateT(image_type, width_3, height_3, bpp);
+ if(NULL == dst3) {
+ FreeImage_Unload(dst2);
+ return NULL;
+ }
+
+ if(dSinE >= 0) {
+ // Positive angle
+ dOffset = (src_width - 1.0) * dSinE * -dTan;
+ }
+ else {
+ // Negative angle
+ dOffset = dTan * ( (src_width - 1.0) * -dSinE + (1.0 - height_3) );
+ }
+ for(u = 0; u < height_3; u++, dOffset += dTan) {
+ int iShear = int(floor(dOffset));
+ HorizontalSkew(dst2, dst3, u, iShear, dOffset - double(iShear), bkcolor);
+ }
+ // Free result of 2nd shear
+ FreeImage_Unload(dst2);
+
+ // Return result of 3rd shear
+ return dst3;
+}
+
+/**
+Rotates a 1-, 8-, 24- or 32-bit image by a given angle (given in degree).
+Angle is unlimited, except for 1-bit images (limited to integer multiples of 90 degree).
+3-shears technique is used.
+@param src Pointer to source image to rotate
+@param dAngle Rotation angle
+@return Returns a pointer to a newly allocated rotated image if successful, returns NULL otherwise
+*/
+static FIBITMAP*
+RotateAny(FIBITMAP *src, double dAngle, const void *bkcolor) {
+ if(NULL == src) {
+ return NULL;
+ }
+
+ FIBITMAP *image = src;
+
+ while(dAngle >= 360) {
+ // Bring angle to range of (-INF .. 360)
+ dAngle -= 360;
+ }
+ while(dAngle < 0) {
+ // Bring angle to range of [0 .. 360)
+ dAngle += 360;
+ }
+ if((dAngle > 45) && (dAngle <= 135)) {
+ // Angle in (45 .. 135]
+ // Rotate image by 90 degrees into temporary image,
+ // so it requires only an extra rotation angle
+ // of -45 .. +45 to complete rotation.
+ image = Rotate90(src);
+ dAngle -= 90;
+ }
+ else if((dAngle > 135) && (dAngle <= 225)) {
+ // Angle in (135 .. 225]
+ // Rotate image by 180 degrees into temporary image,
+ // so it requires only an extra rotation angle
+ // of -45 .. +45 to complete rotation.
+ image = Rotate180(src);
+ dAngle -= 180;
+ }
+ else if((dAngle > 225) && (dAngle <= 315)) {
+ // Angle in (225 .. 315]
+ // Rotate image by 270 degrees into temporary image,
+ // so it requires only an extra rotation angle
+ // of -45 .. +45 to complete rotation.
+ image = Rotate270(src);
+ dAngle -= 270;
+ }
+
+ // If we got here, angle is in (-45 .. +45]
+
+ if(NULL == image) {
+ // Failed to allocate middle image
+ return NULL;
+ }
+
+ if(0 == dAngle) {
+ if(image == src) {
+ // Nothing to do ...
+ return FreeImage_Clone(src);
+ } else {
+ // No more rotation needed
+ return image;
+ }
+ }
+ else {
+ // Perform last rotation
+ FIBITMAP *dst = Rotate45(image, dAngle, bkcolor);
+
+ if(src != image) {
+ // Middle image was required, free it now.
+ FreeImage_Unload(image);
+ }
+
+ return dst;
+ }
+}
+
+// ==========================================================
+
+FIBITMAP *DLL_CALLCONV
+FreeImage_Rotate(FIBITMAP *dib, double angle, const void *bkcolor) {
+ if(!FreeImage_HasPixels(dib)) return NULL;
+
+ if(0 == angle) {
+ return FreeImage_Clone(dib);
+ }
+ // DIB are stored upside down ...
+ angle *= -1;
+
+ try {
+ unsigned bpp = FreeImage_GetBPP(dib);
+ FREE_IMAGE_TYPE image_type = FreeImage_GetImageType(dib);
+
+ switch(image_type) {
+ case FIT_BITMAP:
+ if(bpp == 1) {
+ // only rotate for integer multiples of 90 degree
+ if(fmod(angle, 90) != 0)
+ return NULL;
+
+ // perform the rotation
+ FIBITMAP *dst = RotateAny(dib, angle, bkcolor);
+ if(!dst) throw(1);
+
+ // build a greyscale palette
+ RGBQUAD *dst_pal = FreeImage_GetPalette(dst);
+ if(FreeImage_GetColorType(dib) == FIC_MINISBLACK) {
+ dst_pal[0].rgbRed = dst_pal[0].rgbGreen = dst_pal[0].rgbBlue = 0;
+ dst_pal[1].rgbRed = dst_pal[1].rgbGreen = dst_pal[1].rgbBlue = 255;
+ } else {
+ dst_pal[0].rgbRed = dst_pal[0].rgbGreen = dst_pal[0].rgbBlue = 255;
+ dst_pal[1].rgbRed = dst_pal[1].rgbGreen = dst_pal[1].rgbBlue = 0;
+ }
+
+ // copy metadata from src to dst
+ FreeImage_CloneMetadata(dst, dib);
+
+ return dst;
+ }
+ else if((bpp == 8) || (bpp == 24) || (bpp == 32)) {
+ FIBITMAP *dst = RotateAny(dib, angle, bkcolor);
+ if(!dst) throw(1);
+
+ if(bpp == 8) {
+ // copy original palette to rotated bitmap
+ RGBQUAD *src_pal = FreeImage_GetPalette(dib);
+ RGBQUAD *dst_pal = FreeImage_GetPalette(dst);
+ memcpy(&dst_pal[0], &src_pal[0], 256 * sizeof(RGBQUAD));
+
+ // copy transparency table
+ FreeImage_SetTransparencyTable(dst, FreeImage_GetTransparencyTable(dib), FreeImage_GetTransparencyCount(dib));
+
+ // copy background color
+ RGBQUAD bkcolor;
+ if( FreeImage_GetBackgroundColor(dib, &bkcolor) ) {
+ FreeImage_SetBackgroundColor(dst, &bkcolor);
+ }
+
+ }
+
+ // copy metadata from src to dst
+ FreeImage_CloneMetadata(dst, dib);
+
+ return dst;
+ }
+ break;
+ case FIT_UINT16:
+ case FIT_RGB16:
+ case FIT_RGBA16:
+ case FIT_FLOAT:
+ case FIT_RGBF:
+ case FIT_RGBAF:
+ {
+ FIBITMAP *dst = RotateAny(dib, angle, bkcolor);
+ if(!dst) throw(1);
+
+ // copy metadata from src to dst
+ FreeImage_CloneMetadata(dst, dib);
+
+ return dst;
+ }
+ break;
+ }
+
+ } catch(int) {
+ return NULL;
+ }
+
+ return NULL;
+}
+
|