summaryrefslogtreecommitdiff
path: root/plugins/AdvaImg/src/FreeImageToolkit/Resize.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'plugins/AdvaImg/src/FreeImageToolkit/Resize.cpp')
-rw-r--r--plugins/AdvaImg/src/FreeImageToolkit/Resize.cpp656
1 files changed, 656 insertions, 0 deletions
diff --git a/plugins/AdvaImg/src/FreeImageToolkit/Resize.cpp b/plugins/AdvaImg/src/FreeImageToolkit/Resize.cpp
new file mode 100644
index 0000000000..5421bd47ab
--- /dev/null
+++ b/plugins/AdvaImg/src/FreeImageToolkit/Resize.cpp
@@ -0,0 +1,656 @@
+// ==========================================================
+// Upsampling / downsampling classes
+//
+// Design and implementation by
+// - Hervé Drolon (drolon@infonie.fr)
+// - Detlev Vendt (detlev.vendt@brillit.de)
+//
+// 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!
+// ==========================================================
+
+#include "Resize.h"
+
+/**
+ Filter weights table.
+ This class stores contribution information for an entire line (row or column).
+*/
+CWeightsTable::CWeightsTable(CGenericFilter *pFilter, unsigned uDstSize, unsigned uSrcSize) {
+ unsigned u;
+ double dWidth;
+ double dFScale = 1.0;
+ const double dFilterWidth = pFilter->GetWidth();
+
+ // scale factor
+ const double dScale = double(uDstSize) / double(uSrcSize);
+
+ if(dScale < 1.0) {
+ // minification
+ dWidth = dFilterWidth / dScale;
+ dFScale = dScale;
+ } else {
+ // magnification
+ dWidth= dFilterWidth;
+ }
+
+ // allocate a new line contributions structure
+ //
+ // window size is the number of sampled pixels
+ m_WindowSize = 2 * (int)ceil(dWidth) + 1;
+ m_LineLength = uDstSize;
+ // allocate list of contributions
+ m_WeightTable = (Contribution*)malloc(m_LineLength * sizeof(Contribution));
+ for(u = 0 ; u < m_LineLength ; u++) {
+ // allocate contributions for every pixel
+ m_WeightTable[u].Weights = (double*)malloc(m_WindowSize * sizeof(double));
+ }
+
+ // offset for discrete to continuous coordinate conversion
+ const double dOffset = (0.5 / dScale) - 0.5;
+
+
+ for(u = 0; u < m_LineLength; u++) {
+ // scan through line of contributions
+ const double dCenter = (double)u / dScale + dOffset; // reverse mapping
+ // find the significant edge points that affect the pixel
+ int iLeft = MAX (0, (int)floor (dCenter - dWidth));
+ int iRight = MIN ((int)ceil (dCenter + dWidth), int(uSrcSize) - 1);
+
+ // cut edge points to fit in filter window in case of spill-off
+ if ((iRight - iLeft + 1) > int(m_WindowSize)) {
+ if(iLeft < (int(uSrcSize) - 1 / 2)) {
+ iLeft++;
+ } else {
+ iRight--;
+ }
+ }
+
+ m_WeightTable[u].Left = iLeft;
+ m_WeightTable[u].Right = iRight;
+
+ int iSrc = 0;
+ double dTotalWeight = 0; // zero sum of weights
+ for(iSrc = iLeft; iSrc <= iRight; iSrc++) {
+ // calculate weights
+ const double weight = dFScale * pFilter->Filter(dFScale * (dCenter - (double)iSrc));
+ m_WeightTable[u].Weights[iSrc-iLeft] = weight;
+ dTotalWeight += weight;
+ }
+ if ((dTotalWeight > 0) && (dTotalWeight != 1)) {
+ // normalize weight of neighbouring points
+ for(iSrc = iLeft; iSrc <= iRight; iSrc++) {
+ // normalize point
+ m_WeightTable[u].Weights[iSrc-iLeft] /= dTotalWeight;
+ }
+ // simplify the filter, discarding null weights at the right
+ iSrc = iRight - iLeft;
+ while(m_WeightTable[u].Weights[iSrc] == 0){
+ m_WeightTable[u].Right--;
+ iSrc--;
+ if(m_WeightTable[u].Right == m_WeightTable[u].Left)
+ break;
+ }
+
+ }
+ }
+}
+
+CWeightsTable::~CWeightsTable() {
+ for(unsigned u = 0; u < m_LineLength; u++) {
+ // free contributions for every pixel
+ free(m_WeightTable[u].Weights);
+ }
+ // free list of pixels contributions
+ free(m_WeightTable);
+}
+
+// ---------------------------------------------
+
+/**
+ CResizeEngine<br>
+ This class performs filtered zoom. It scales an image to the desired dimensions with
+ any of the CGenericFilter derived filter class.<br>
+ It works with 8-, 24- and 32-bit buffers.<br><br>
+
+ <b>References</b> : <br>
+ [1] Paul Heckbert, C code to zoom raster images up or down, with nice filtering.
+ UC Berkeley, August 1989. [online] http://www-2.cs.cmu.edu/afs/cs.cmu.edu/Web/People/ph/heckbert.html
+ [2] Eran Yariv, Two Pass Scaling using Filters. The Code Project, December 1999.
+ [online] http://www.codeproject.com/bitmap/2_pass_scaling.asp
+
+*/
+
+FIBITMAP* CResizeEngine::scale(FIBITMAP *src, unsigned dst_width, unsigned dst_height) {
+ unsigned src_width = FreeImage_GetWidth(src);
+ unsigned src_height = FreeImage_GetHeight(src);
+
+ unsigned redMask = FreeImage_GetRedMask(src);
+ unsigned greenMask = FreeImage_GetGreenMask(src);
+ unsigned blueMask = FreeImage_GetBlueMask(src);
+
+ unsigned bpp = FreeImage_GetBPP(src);
+ if(bpp == 1) {
+ // convert output to 8-bit
+ bpp = 8;
+ }
+
+ FREE_IMAGE_TYPE image_type = FreeImage_GetImageType(src);
+
+ // allocate the dst image
+ FIBITMAP *dst = FreeImage_AllocateT(image_type, dst_width, dst_height, bpp, redMask, greenMask, blueMask);
+ if (!dst) return NULL;
+
+ if(bpp == 8) {
+ if(FreeImage_GetColorType(src) == FIC_MINISWHITE) {
+ // build an inverted greyscale palette
+ RGBQUAD *dst_pal = FreeImage_GetPalette(dst);
+ for(unsigned i = 0; i < 256; i++) {
+ dst_pal[i].rgbRed = dst_pal[i].rgbGreen = dst_pal[i].rgbBlue = (BYTE)(255 - i);
+ }
+ } else {
+ // build a greyscale palette
+ RGBQUAD *dst_pal = FreeImage_GetPalette(dst);
+ for(unsigned i = 0; i < 256; i++) {
+ dst_pal[i].rgbRed = dst_pal[i].rgbGreen = dst_pal[i].rgbBlue = (BYTE)i;
+ }
+ }
+ }
+
+ /**
+ Decide which filtering order (xy or yx) is faster for this mapping.
+ --- The theory ---
+ Try to minimize calculations by counting the number of convolution multiplies
+ if(dst_width*src_height <= src_width*dst_height) {
+ // xy filtering
+ } else {
+ // yx filtering
+ }
+ --- The practice ---
+ Try to minimize calculations by counting the number of vertical convolutions (the most time consuming task)
+ if(dst_width*dst_height <= src_width*dst_height) {
+ // xy filtering
+ } else {
+ // yx filtering
+ }
+ */
+
+ if(dst_width <= src_width) {
+ // xy filtering
+ // -------------
+
+ // allocate a temporary image
+ FIBITMAP *tmp = FreeImage_AllocateT(image_type, dst_width, src_height, bpp, redMask, greenMask, blueMask);
+ if (!tmp) {
+ FreeImage_Unload(dst);
+ return NULL;
+ }
+
+ // scale source image horizontally into temporary image
+ horizontalFilter(src, src_width, src_height, tmp, dst_width, src_height);
+
+ // scale temporary image vertically into result image
+ verticalFilter(tmp, dst_width, src_height, dst, dst_width, dst_height);
+
+ // free temporary image
+ FreeImage_Unload(tmp);
+
+ } else {
+ // yx filtering
+ // -------------
+
+ // allocate a temporary image
+ FIBITMAP *tmp = FreeImage_AllocateT(image_type, src_width, dst_height, bpp, redMask, greenMask, blueMask);
+ if (!tmp) {
+ FreeImage_Unload(dst);
+ return NULL;
+ }
+
+ // scale source image vertically into temporary image
+ verticalFilter(src, src_width, src_height, tmp, src_width, dst_height);
+
+ // scale temporary image horizontally into result image
+ horizontalFilter(tmp, src_width, dst_height, dst, dst_width, dst_height);
+
+ // free temporary image
+ FreeImage_Unload(tmp);
+ }
+
+ return dst;
+}
+
+
+/// Performs horizontal image filtering
+void CResizeEngine::horizontalFilter(FIBITMAP *src, unsigned src_width, unsigned src_height, FIBITMAP *dst, unsigned dst_width, unsigned dst_height) {
+ if(dst_width == src_width) {
+ // no scaling required, just copy
+ switch(FreeImage_GetBPP(src)) {
+ case 1:
+ {
+ if(FreeImage_GetBPP(dst) != 8) break;
+ for(unsigned y = 0; y < dst_height; y++) {
+ // convert each row
+ BYTE *src_bits = FreeImage_GetScanLine(src, y);
+ BYTE *dst_bits = FreeImage_GetScanLine(dst, y);
+ FreeImage_ConvertLine1To8(dst_bits, src_bits, dst_width);
+ }
+ }
+ break;
+
+ default:
+ {
+ const BYTE *src_bits = FreeImage_GetBits(src);
+ BYTE *dst_bits = FreeImage_GetBits(dst);
+ memcpy(dst_bits, src_bits, dst_height * FreeImage_GetPitch(dst));
+ }
+ break;
+ }
+ }
+ else {
+
+ // allocate and calculate the contributions
+ CWeightsTable weightsTable(m_pFilter, dst_width, src_width);
+
+ // step through rows
+ switch(FreeImage_GetImageType(src)) {
+ case FIT_BITMAP:
+ {
+ switch(FreeImage_GetBPP(src)) {
+ case 1:
+ {
+ // scale and convert to 8-bit
+ if(FreeImage_GetBPP(dst) != 8) break;
+
+ for(unsigned y = 0; y < dst_height; y++) {
+ // scale each row
+ const BYTE *src_bits = FreeImage_GetScanLine(src, y);
+ BYTE *dst_bits = FreeImage_GetScanLine(dst, y);
+
+ for(unsigned x = 0; x < dst_width; x++) {
+ // loop through row
+ double value = 0;
+ const unsigned iLeft = weightsTable.getLeftBoundary(x); // retrieve left boundary
+ const unsigned iRight = weightsTable.getRightBoundary(x); // retrieve right boundary
+
+ for(unsigned i = iLeft; i <= iRight; i++) {
+ // scan between boundaries
+ // accumulate weighted effect of each neighboring pixel
+ const double weight = weightsTable.getWeight(x, i-iLeft);
+
+ const BYTE pixel = (src_bits[i >> 3] & (0x80 >> (i & 0x07))) != 0;
+ value += (weight * (double)pixel);
+ }
+ value *= 255;
+
+ // clamp and place result in destination pixel
+ dst_bits[x] = (BYTE)CLAMP<int>((int)(value + 0.5), 0, 255);
+ }
+ }
+ }
+ break;
+
+ case 8:
+ case 24:
+ case 32:
+ {
+ // Calculate the number of bytes per pixel (1 for 8-bit, 3 for 24-bit or 4 for 32-bit)
+ const unsigned bytespp = FreeImage_GetLine(src) / FreeImage_GetWidth(src);
+
+ for(unsigned y = 0; y < dst_height; y++) {
+ // scale each row
+ const BYTE *src_bits = FreeImage_GetScanLine(src, y);
+ BYTE *dst_bits = FreeImage_GetScanLine(dst, y);
+
+ for(unsigned x = 0; x < dst_width; x++) {
+ // loop through row
+ double value[4] = {0, 0, 0, 0}; // 4 = 32 bpp max
+ const unsigned iLeft = weightsTable.getLeftBoundary(x); // retrieve left boundary
+ const unsigned iRight = weightsTable.getRightBoundary(x); // retrieve right boundary
+
+ for(unsigned i = iLeft; i <= iRight; i++) {
+ // scan between boundaries
+ // accumulate weighted effect of each neighboring pixel
+ const double weight = weightsTable.getWeight(x, i-iLeft);
+
+ unsigned index = i * bytespp; // pixel index
+ for (unsigned j = 0; j < bytespp; j++) {
+ value[j] += (weight * (double)src_bits[index++]);
+ }
+ }
+
+ // clamp and place result in destination pixel
+ for (unsigned j = 0; j < bytespp; j++) {
+ dst_bits[j] = (BYTE)CLAMP<int>((int)(value[j] + 0.5), 0, 0xFF);
+ }
+
+ dst_bits += bytespp;
+ }
+ }
+ }
+ break;
+ }
+ }
+ break;
+
+ case FIT_UINT16:
+ case FIT_RGB16:
+ case FIT_RGBA16:
+ {
+ // Calculate the number of words per pixel (1 for 16-bit, 3 for 48-bit or 4 for 64-bit)
+ const unsigned wordspp = (FreeImage_GetLine(src) / FreeImage_GetWidth(src)) / sizeof(WORD);
+
+ for(unsigned y = 0; y < dst_height; y++) {
+ // scale each row
+ const WORD *src_bits = (WORD*)FreeImage_GetScanLine(src, y);
+ WORD *dst_bits = (WORD*)FreeImage_GetScanLine(dst, y);
+
+ for(unsigned x = 0; x < dst_width; x++) {
+ // loop through row
+ double value[4] = {0, 0, 0, 0}; // 4 = 64 bpp max
+ const unsigned iLeft = weightsTable.getLeftBoundary(x); // retrieve left boundary
+ const unsigned iRight = weightsTable.getRightBoundary(x); // retrieve right boundary
+
+ for(unsigned i = iLeft; i <= iRight; i++) {
+ // scan between boundaries
+ // accumulate weighted effect of each neighboring pixel
+ const double weight = weightsTable.getWeight(x, i-iLeft);
+
+ unsigned index = i * wordspp; // pixel index
+ for (unsigned j = 0; j < wordspp; j++) {
+ value[j] += (weight * (double)src_bits[index++]);
+ }
+ }
+
+ // clamp and place result in destination pixel
+ for (unsigned j = 0; j < wordspp; j++) {
+ dst_bits[j] = (WORD)CLAMP<int>((int)(value[j] + 0.5), 0, 0xFFFF);
+ }
+
+ dst_bits += wordspp;
+ }
+ }
+ }
+ break;
+
+ case FIT_FLOAT:
+ case FIT_RGBF:
+ case FIT_RGBAF:
+ {
+ // Calculate the number of floats per pixel (1 for 32-bit, 3 for 96-bit or 4 for 128-bit)
+ const unsigned floatspp = (FreeImage_GetLine(src) / FreeImage_GetWidth(src)) / sizeof(float);
+
+ for(unsigned y = 0; y < dst_height; y++) {
+ // scale each row
+ const float *src_bits = (float*)FreeImage_GetScanLine(src, y);
+ float *dst_bits = (float*)FreeImage_GetScanLine(dst, y);
+
+ for(unsigned x = 0; x < dst_width; x++) {
+ // loop through row
+ double value[4] = {0, 0, 0, 0}; // 4 = 128 bpp max
+ const unsigned iLeft = weightsTable.getLeftBoundary(x); // retrieve left boundary
+ const unsigned iRight = weightsTable.getRightBoundary(x); // retrieve right boundary
+
+ for(unsigned i = iLeft; i <= iRight; i++) {
+ // scan between boundaries
+ // accumulate weighted effect of each neighboring pixel
+ const double weight = weightsTable.getWeight(x, i-iLeft);
+
+ unsigned index = i * floatspp; // pixel index
+ for (unsigned j = 0; j < floatspp; j++) {
+ value[j] += (weight * (double)src_bits[index++]);
+ }
+ }
+
+ // place result in destination pixel
+ for (unsigned j = 0; j < floatspp; j++) {
+ dst_bits[j] = (float)value[j];
+ }
+
+ dst_bits += floatspp;
+ }
+ }
+ }
+ break;
+
+ }
+ }
+}
+
+/// Performs vertical image filtering
+void CResizeEngine::verticalFilter(FIBITMAP *src, unsigned src_width, unsigned src_height, FIBITMAP *dst, unsigned dst_width, unsigned dst_height) {
+ if(src_height == dst_height) {
+ // no scaling required, just copy
+ switch(FreeImage_GetBPP(src)) {
+ case 1:
+ {
+ if(FreeImage_GetBPP(dst) != 8) break;
+ for(unsigned y = 0; y < dst_height; y++) {
+ // convert each row
+ BYTE *src_bits = FreeImage_GetScanLine(src, y);
+ BYTE *dst_bits = FreeImage_GetScanLine(dst, y);
+ FreeImage_ConvertLine1To8(dst_bits, src_bits, dst_width);
+ }
+ }
+ break;
+
+ default:
+ {
+ const BYTE *src_bits = FreeImage_GetBits(src);
+ BYTE *dst_bits = FreeImage_GetBits(dst);
+ memcpy(dst_bits, src_bits, dst_height * FreeImage_GetPitch(dst));
+ }
+ break;
+ }
+
+ }
+ else {
+
+ // allocate and calculate the contributions
+ CWeightsTable weightsTable(m_pFilter, dst_height, src_height);
+
+ // step through columns
+ switch(FreeImage_GetImageType(src)) {
+ case FIT_BITMAP:
+ {
+ switch(FreeImage_GetBPP(src)) {
+ case 1:
+ {
+ // scale and convert to 8-bit
+ if(FreeImage_GetBPP(dst) != 8) break;
+
+ const unsigned src_pitch = FreeImage_GetPitch(src);
+ const unsigned dst_pitch = FreeImage_GetPitch(dst);
+
+ for(unsigned x = 0; x < dst_width; x++) {
+
+ // work on column x in dst
+ BYTE *dst_bits = FreeImage_GetBits(dst) + x;
+
+ // scale each column
+ for(unsigned y = 0; y < dst_height; y++) {
+ // loop through column
+ double value = 0;
+ const unsigned iLeft = weightsTable.getLeftBoundary(y); // retrieve left boundary
+ const unsigned iRight = weightsTable.getRightBoundary(y); // retrieve right boundary
+
+ BYTE *src_bits = FreeImage_GetScanLine(src, iLeft);
+
+ for(unsigned i = iLeft; i <= iRight; i++) {
+ // scan between boundaries
+ // accumulate weighted effect of each neighboring pixel
+ const double weight = weightsTable.getWeight(y, i-iLeft);
+
+ const BYTE pixel = (src_bits[x >> 3] & (0x80 >> (x & 0x07))) != 0;
+ value += (weight * (double)pixel);
+
+ src_bits += src_pitch;
+ }
+ value *= 255;
+
+ // clamp and place result in destination pixel
+ *dst_bits = (BYTE)CLAMP<int>((int)(value + 0.5), 0, 0xFF);
+
+ dst_bits += dst_pitch;
+ }
+ }
+ }
+ break;
+
+ case 8:
+ case 24:
+ case 32:
+ {
+ // Calculate the number of bytes per pixel (1 for 8-bit, 3 for 24-bit or 4 for 32-bit)
+ const unsigned bytespp = FreeImage_GetLine(src) / FreeImage_GetWidth(src);
+
+ const unsigned src_pitch = FreeImage_GetPitch(src);
+ const unsigned dst_pitch = FreeImage_GetPitch(dst);
+
+ for(unsigned x = 0; x < dst_width; x++) {
+ const unsigned index = x * bytespp; // pixel index
+
+ // work on column x in dst
+ BYTE *dst_bits = FreeImage_GetBits(dst) + index;
+
+ // scale each column
+ for(unsigned y = 0; y < dst_height; y++) {
+ // loop through column
+ double value[4] = {0, 0, 0, 0}; // 4 = 32 bpp max
+ const unsigned iLeft = weightsTable.getLeftBoundary(y); // retrieve left boundary
+ const unsigned iRight = weightsTable.getRightBoundary(y); // retrieve right boundary
+
+ const BYTE *src_bits = FreeImage_GetScanLine(src, iLeft) + index;
+
+ for(unsigned i = iLeft; i <= iRight; i++) {
+ // scan between boundaries
+ // accumulate weighted effect of each neighboring pixel
+ const double weight = weightsTable.getWeight(y, i-iLeft);
+ for (unsigned j = 0; j < bytespp; j++) {
+ value[j] += (weight * (double)src_bits[j]);
+ }
+
+ src_bits += src_pitch;
+ }
+
+ // clamp and place result in destination pixel
+ for (unsigned j = 0; j < bytespp; j++) {
+ dst_bits[j] = (BYTE)CLAMP<int>((int)(value[j] + 0.5), 0, 0xFF);
+ }
+
+ dst_bits += dst_pitch;
+ }
+ }
+ }
+ break;
+ }
+ }
+ break;
+
+ case FIT_UINT16:
+ case FIT_RGB16:
+ case FIT_RGBA16:
+ {
+ // Calculate the number of words per pixel (1 for 16-bit, 3 for 48-bit or 4 for 64-bit)
+ const unsigned wordspp = (FreeImage_GetLine(src) / FreeImage_GetWidth(src)) / sizeof(WORD);
+
+ const unsigned src_pitch = FreeImage_GetPitch(src) / sizeof(WORD);
+ const unsigned dst_pitch = FreeImage_GetPitch(dst) / sizeof(WORD);
+
+ for(unsigned x = 0; x < dst_width; x++) {
+ const unsigned index = x * wordspp; // pixel index
+
+ // work on column x in dst
+ WORD *dst_bits = (WORD*)FreeImage_GetBits(dst) + index;
+
+ // scale each column
+ for(unsigned y = 0; y < dst_height; y++) {
+ // loop through column
+ double value[4] = {0, 0, 0, 0}; // 4 = 64 bpp max
+ const unsigned iLeft = weightsTable.getLeftBoundary(y); // retrieve left boundary
+ const unsigned iRight = weightsTable.getRightBoundary(y); // retrieve right boundary
+
+ const WORD *src_bits = (WORD*)FreeImage_GetScanLine(src, iLeft) + index;
+
+ for(unsigned i = iLeft; i <= iRight; i++) {
+ // scan between boundaries
+ // accumulate weighted effect of each neighboring pixel
+ const double weight = weightsTable.getWeight(y, i-iLeft);
+ for (unsigned j = 0; j < wordspp; j++) {
+ value[j] += (weight * (double)src_bits[j]);
+ }
+
+ src_bits += src_pitch;
+ }
+
+ // clamp and place result in destination pixel
+ for (unsigned j = 0; j < wordspp; j++) {
+ dst_bits[j] = (WORD)CLAMP<int>((int)(value[j] + 0.5), 0, 0xFFFF);
+ }
+
+ dst_bits += dst_pitch;
+ }
+ }
+ }
+ break;
+
+ case FIT_FLOAT:
+ case FIT_RGBF:
+ case FIT_RGBAF:
+ {
+ // Calculate the number of floats per pixel (1 for 32-bit, 3 for 96-bit or 4 for 128-bit)
+ const unsigned floatspp = (FreeImage_GetLine(src) / FreeImage_GetWidth(src)) / sizeof(float);
+
+ const unsigned src_pitch = FreeImage_GetPitch(src) / sizeof(float);
+ const unsigned dst_pitch = FreeImage_GetPitch(dst) / sizeof(float);
+
+ for(unsigned x = 0; x < dst_width; x++) {
+ const unsigned index = x * floatspp; // pixel index
+
+ // work on column x in dst
+ float *dst_bits = (float*)FreeImage_GetBits(dst) + index;
+
+ // scale each column
+ for(unsigned y = 0; y < dst_height; y++) {
+ // loop through column
+ double value[4] = {0, 0, 0, 0}; // 4 = 128 bpp max
+ const unsigned iLeft = weightsTable.getLeftBoundary(y); // retrieve left boundary
+ const unsigned iRight = weightsTable.getRightBoundary(y); // retrieve right boundary
+
+ const float *src_bits = (float*)FreeImage_GetScanLine(src, iLeft) + index;
+
+ for(unsigned i = iLeft; i <= iRight; i++) {
+ // scan between boundaries
+ // accumulate weighted effect of each neighboring pixel
+ const double weight = weightsTable.getWeight(y, i-iLeft);
+ for (unsigned j = 0; j < floatspp; j++) {
+ value[j] += (weight * (double)src_bits[j]);
+ }
+
+ src_bits += src_pitch;
+ }
+
+ // clamp and place result in destination pixel
+ for (unsigned j = 0; j < floatspp; j++) {
+ dst_bits[j] = (float)value[j];
+ }
+
+ dst_bits += dst_pitch;
+ }
+ }
+ }
+ break;
+
+ }
+ }
+}
+