Aegisub/aegisub/subtitle_format_prs.cpp
Amar Takhar 0763541848 Change how configuration works.
* move win32/config0.h -> config/config_windows0.h
  * move win32/stdint.h -> msvc/stdint.h
  * move posix/defines.h -> config/config_unix.h
  * add config.h - brings in config_(windows|unix).h as required
  * add config.h to *.cpp
  * Self-contain FFmpegSource2 with required function defines wrapped with
    __UNIX__ instead of the now removed defines.h.
  * Edit aegisub_vs2008.vcproj to remove explicit inclusion of config.h, also
    change VCPreBuildEventTool to create windows_config.h from
    windows_config0.h.  Add msvc to include path.
  * Change configure to create ./acconf.h instead of posix/acconf.h

This will allow us to create a more standard and platform agnostic way of
configuration aegsisub during build time.

Originally committed to SVN as r2621.
2009-01-04 06:31:48 +00:00

798 lines
22 KiB
C++

// Copyright (c) 2006, Rodrigo Braz Monteiro
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
// * Neither the name of the Aegisub Group nor the names of its contributors
// may be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// -----------------------------------------------------------------------------
//
// AEGISUB
//
// Website: http://aegisub.cellosoft.com
// Contact: mailto:zeratul@cellosoft.com
//
///////////
// Headers
#include "config.h"
#if USE_PRS == 1
#include <wx/image.h>
#include <wx/mstream.h>
#include <wx/filename.h>
#include <wx/docview.h>
#include "subtitle_format_prs.h"
#include "ass_file.h"
#include "ass_dialogue.h"
#include "ass_override.h"
#include "avisynth_wrap.h"
#include "video_box.h"
#include "video_display.h"
#include "video_provider.h"
#include "main.h"
#include "frame_main.h"
#include "vfr.h"
#include "utils.h"
#include "md5.h"
#include "dialog_progress.h"
#include "../prs/prs.h"
//////////////////////
// Can write to file?
bool PRSSubtitleFormat::CanWriteFile(wxString filename) {
#ifdef __WINDOWS__
return false;
//return (filename.Right(4).Lower() == _T(".prs"));
#else
return false;
#endif
}
////////////
// Get name
wxString PRSSubtitleFormat::GetName() {
return _T("Pre-Rendered Subtitles");
}
///////////////////////
// Get write wildcards
wxArrayString PRSSubtitleFormat::GetWriteWildcards() {
wxArrayString formats;
formats.Add(_T("prs"));
return formats;
}
//////////////
// Write file
void PRSSubtitleFormat::WriteFile(wxString filename,wxString encoding) {
#ifdef __WINDOWS__
// Video loaded?
if (VideoContext::Get()->IsLoaded()) throw _T("Video not loaded!");
// Create the PRS file
PRSFile file;
// Create the temporary .ass file
wxString tempFile1 = wxFileName::CreateTempFileName(_T("aegisub"));
wxRemoveFile(tempFile1);
wxString tempFile = tempFile1 + _T(".ass");
GetAssFile()->Save(tempFile,false,false);
// Open two Avisynth environments
AviSynthWrapper avs1,avs2;
IScriptEnvironment *env1 = avs1.GetEnv();
IScriptEnvironment *env2 = avs2.GetEnv();
// Prepare the Avisynth environments, that is, generate blank clips and hardsub into them
wxString val = wxString::Format(_T("BlankClip(pixel_type=\"RGB32\",length=%i,width=%i,height=%i,fps=%f"),VideoContext::Get()->GetLength(),VideoContext::Get()->GetWidth(),VideoContext::Get()->GetHeight(),VideoContext::Get()->GetFPS());
AVSValue script1 = env1->Invoke("Eval",AVSValue(wxString(val + _T(",color=$000000)")).mb_str(wxConvUTF8)));
AVSValue script2 = env2->Invoke("Eval",AVSValue(wxString(val + _T(",color=$FFFFFF)")).mb_str(wxConvUTF8)));
char temp[512];
strcpy(temp,tempFile.mb_str(wxConvLocal));
AVSValue args1[2] = { script1.AsClip(), temp };
AVSValue args2[2] = { script2.AsClip(), temp };
try {
script1 = env1->Invoke("TextSub", AVSValue(args1,2));
script2 = env2->Invoke("TextSub", AVSValue(args2,2));
}
catch (AvisynthError &err) {
throw _T("AviSynth error: ") + wxString(err.msg,wxConvLocal);
}
PClip clip1 = script1.AsClip();
PClip clip2 = script2.AsClip();
// Get range
std::vector<int> frames = GetFrameRanges();
int totalFrames = frames.size();
int toDraw = 0;
for (int i=0;i<totalFrames;i++) {
if (frames[i] == 2) toDraw++;
}
// Set variables
id = 0;
lastDisplay = NULL;
optimizer = 1; // 0 = none, 1 = optipng, 2 = pngout
// Progress
bool canceled = false;
DialogProgress *progress = new DialogProgress(NULL,_("Exporting PRS"),&canceled,_("Writing file"),0,toDraw);
progress->Show();
progress->SetProgress(0,toDraw);
// Render all frames that were detected to contain subtitles
int lastFrameDrawn = 0;
int drawn = 0;
for (int framen=0;framen<totalFrames;framen++) {
// Canceled?
if (canceled) break;
// Is this frame supposed to be rendered?
if (frames[framen] == 0) continue;
// Update progress
progress->SetProgress(drawn,toDraw);
progress->SetText(wxString::Format(_T("Writing PRS file. Line: %i/%i (%.2f%%)"),framen,totalFrames,MIN(float(drawn)*100/toDraw,100.0)));
if (frames[framen] == 2) drawn++;
// Read the frame image
PVideoFrame frame1 = clip1->GetFrame(framen,env1);
PVideoFrame frame2 = clip2->GetFrame(framen,env2);
// Prepare to get wxImage
int x=0,y=0;
int maxalpha=0;
// Get wxImage
wxImage bmp = CalculateAlpha(frame1->GetReadPtr(),frame2->GetReadPtr(),frame1->GetRowSize(),frame1->GetHeight(),frame1->GetPitch(),&x,&y,&maxalpha);
if (!bmp.Ok()) continue;
lastFrameDrawn = framen;
// Get the list of rectangles
std::vector<wxRect> rects;
GetSubPictureRectangles(bmp,rects);
// Add each sub-image to file
int nrects = rects.size();
int useFrameN;
for (int i=0;i<nrects;i++) {
// Pick either full image or subimage, as appropriate
wxImage curImage;
if (rects[i].x == 0 && rects[i].y == 0 && rects[i].width == bmp.GetWidth() && rects[i].height == bmp.GetHeight()) curImage = bmp;
else curImage = SubImageWithAlpha(bmp,rects[i]);
if (!curImage.Ok()) continue;
// Optimize image
OptimizeImage(curImage);
// Insert the image
useFrameN = framen;
InsertFrame(file,useFrameN,frames,curImage,x+rects[i].x,y+rects[i].y,maxalpha);
}
framen = useFrameN;
}
// Destroy progress bar
if (!canceled) progress->Destroy();
else return;
// Save file
file.Save((const char*)filename.mb_str(wxConvLocal));
wxString filename2 = filename + _T(".prsa");
file.SaveText((const char*)filename2.mb_str(wxConvLocal));
// Delete temp file
wxRemoveFile(tempFile);
#endif
}
//////////////////////////
// Insert frame into file
void PRSSubtitleFormat::InsertFrame(PRSFile &file,int &framen,std::vector<int> &frames,wxImage &bmp,int x,int y,int maxalpha) {
// Generic data holder
size_t datasize = 0;
char *rawData = NULL;
std::vector<char> data;
//bmp.SaveFile(wxString::Format(_T("test_%i.png"),id),wxBITMAP_TYPE_PNG);
// pngout/optipng optimize
if (optimizer) {
// Get temporary filename
wxString tempFile = wxFileName::CreateTempFileName(_T("aegiprs"));
wxString tempOut = tempFile + _T("out.png");
// Prepare arrays to capture output
wxArrayString output;
wxArrayString errors;
// Generate the temporary PNG and run the optimizer program on it
if (optimizer == 1) {
bmp.SaveFile(tempOut,wxBITMAP_TYPE_PNG);
wxExecute(AegisubApp::folderName + _T("optipng.exe -zc9 -zm8 -zs0-3 -f0 ") + tempOut,output,errors);
}
if (optimizer == 2) {
bmp.SaveFile(tempFile,wxBITMAP_TYPE_PNG);
wxExecute(AegisubApp::folderName + _T("pngout.exe ") + tempFile + _T(" ") + tempOut + _T(" /f0 /y /q"),output,errors);
}
// Read file back
FILE *fp = fopen(tempOut.mb_str(wxConvLocal),"rb");
fseek(fp,0,SEEK_END);
datasize = ftell(fp);
data.resize(datasize);
rawData = &data[0];
rewind(fp);
fread(rawData,1,datasize,fp);
fclose(fp);
// Destroy temporary files
wxRemoveFile(tempFile);
wxRemoveFile(tempOut);
}
// No optimization (much faster)
else {
// Convert wxImage to PNG directly
wxMemoryOutputStream stream;
bmp.SaveFile(stream,wxBITMAP_TYPE_PNG);
datasize = stream.GetSize();
data.resize(datasize);
rawData = &data[0];
stream.CopyTo(rawData,datasize);
}
// Find start and end times
int startf = framen;
int totalFrames = frames.size();
while (++framen<totalFrames && frames[framen] == 1);
framen--; // need -1, otherwise all sub-images are extended by one frame
int endf = framen;
int start = VFR_Output.GetTimeAtFrame(startf,true);
int end = VFR_Output.GetTimeAtFrame(endf,false);
// Create PRSImage
PRSImage *img = new PRSImage;
img->id = id;
img->imageType = PNG_IMG;
img->w = bmp.GetWidth();
img->h = bmp.GetHeight();
img->maxAlpha = maxalpha;
img->dataLen = datasize;
img->data = new char[img->dataLen];
memcpy(img->data,rawData,img->dataLen);
// Hash the PRSImage data
md5_state_t state;
md5_init(&state);
md5_append(&state,(md5_byte_t*)img->data,img->dataLen);
md5_finish(&state,(md5_byte_t*)img->md5);
// Check for duplicates
PRSImage *dupe = file.FindDuplicateImage(img);
int useID = id;
// Dupe found, use that instead
if (dupe) {
useID = dupe->id;
delete img;
img = NULL;
}
// Frame is all OK, add it to file
else {
file.AddEntry(img);
id++;
}
// Set blend data
unsigned char alpha = 255;
unsigned char blend = 0;
// Check if it's just an extension of last display
if (lastDisplay && lastDisplay->id == (unsigned)useID && (signed)lastDisplay->endFrame == startf-1 &&
lastDisplay->x == x && lastDisplay->y == y && lastDisplay->alpha == alpha && lastDisplay->blend == blend)
{
lastDisplay->end = start;
lastDisplay->endFrame = startf;
}
// It isn't; needs a new display command
else {
// Create PRSDisplay
PRSDisplay *display = new PRSDisplay;
display->start = start;
display->end = end;
display->startFrame = startf;
display->endFrame = endf;
display->id = useID;
display->x = x;
display->y = y;
display->alpha = alpha;
display->blend = blend;
lastDisplay = display;
// Insert into list
file.AddEntry(display);
}
}
///////////////////////////////////
// Get rectangles of useful glyphs
void PRSSubtitleFormat::GetSubPictureRectangles(wxImage &image,std::vector<wxRect> &rects) {
// Boundaries
int w = image.GetWidth();
int h = image.GetHeight();
int startx = 0;
int starty = 0;
int endx = w-1;
int endy = h-1;
// Variables
bool hasSubImage = false;
bool isBlankRow = true;
const unsigned char *data = image.GetAlpha();
const unsigned char *src = data;
unsigned char a;
// For each row
for (int y=0;y<=h;y++) {
if (y < h) {
// Reset row data
isBlankRow = true;
if (!hasSubImage) {
startx = w;
endx = -1;
}
// Check row
for (int x=0;x<w;x++) {
a = *src++;
if (a) {
isBlankRow = false;
if (x < startx) startx = x;
if (x > endx) endx = x;
}
}
// Set sub image status
if (!isBlankRow && !hasSubImage) {
starty = y;
hasSubImage = true;
}
}
// If the processed row is totally blank and there is a subimage, separate them
if ((isBlankRow && hasSubImage) || y == h) {
// Insert rectangle
endy = y-1;
rects.push_back(wxRect(startx,starty,endx-startx+1,endy-starty+1));
hasSubImage = false;
}
}
}
////////////////////
// Get frame ranges
std::vector<int> PRSSubtitleFormat::GetFrameRanges() {
// Loop through subtitles in file
std::vector<int> frames;
for (entryIter cur=Line->begin();cur!=Line->end();cur++) {
AssDialogue *diag = AssEntry::GetAsDialogue(*cur);
// Dialogue found
if (diag && !diag->Comment) {
// Parse tags
diag->ParseASSTags();
// Check if there is any animation tag, to flag the line as animated, forcing storage of every frame
// THIS NEEDS OPTIMIZATION!
// Currently it will redraw whole line, even if only some time of it is animated.
// This is later hopefully removed by duplicate checker, but it would be faster if done here
bool hasAnimation = false;
int blocks = diag->Blocks.size();
AssDialogueBlockOverride *block;
for (int i=0;i<blocks;i++) {
block = AssDialogueBlock::GetAsOverride(diag->Blocks[i]);
if (block) {
// Found an override block, see if it contains any animation tags
int tags = block->Tags.size();
for (int j=0;j<tags;j++) {
wxString tagName = block->Tags[j]->Name;
if (tagName == _T("\\t") || tagName == _T("\\move") || tagName == _T("\\k") || tagName == _T("\\K") ||
tagName == _T("\\kf") || tagName == _T("\\ko") || tagName == _T("\\fad") || tagName == _T("\\fade")) {
hasAnimation = true;
}
}
}
}
// Calculate start and end times
size_t start = VFR_Output.GetFrameAtTime(diag->Start.GetMS(),true);
size_t end = VFR_Output.GetFrameAtTime(diag->End.GetMS(),false);
// Ensure that the vector is long enough
// Yes, +1, this is an optimization for something below
if (frames.size() <= end+1) frames.resize(end+2);
// Fill data
// 2 = Store this frame
// 1 = Repeat last frame
// 0 = Don't store this frame
bool lastOn = false;
for (size_t i=start;i<=end;i++) {
// Put a keyframe at the very start, or everywhere if it's animated
if (i == start || hasAnimation) frames[i] = 2;
else {
// Already set to 1 or 2, meaning that another subtitle is here already
if (frames[i] != 0) lastOn = true;
// Set to 0, so nothing is here
else {
// Just came out of a subtitle end, put a keyframe here
if (lastOn) {
frames[i] = 2;
lastOn = false;
}
// Otherwise, just repeat
frames[i] = 1;
}
}
// Ends right before another "1" block, so make this a "2"
if (i == end && frames[i+1] == 1) frames[i] = 2;
}
// Clean up
diag->ClearBlocks();
}
}
// Done
return frames;
}
/////////////////////////////////////////////
// Optimize the image by tweaking the colors
// First, a little macro to help the comparisons down there
#define IN_ERROR_MARGIN(col1,col2,error) ((col1 > col2 ? ((int)(col1-col2)) : ((int)(col2-col1))) <= (error))
// Now, since I don't expect anyone to be able to decypher this...
// This "flood fills" the image based on alpha, to make it easier to compress, without affecting visual quality
// e.g. if you have a pixel with 25% opacity, then a difference of as much as 3 in the color channels won't have a visual impact
void PRSSubtitleFormat::OptimizeImage(wxImage &image) {
// Get the raw data
unsigned char *data = (unsigned char*) image.GetData();
unsigned char *alpha = (unsigned char*) image.GetAlpha();
int w = image.GetWidth();
int h = image.GetHeight();
int len = w*h;
// Create mask for status and fill with zeroes
char *status = new char[len];
for (int i=0;i<len;i++) status[i] = 0;
// Find highest alpha
unsigned char highAlpha = 0;
for (int i=0;i<len;i++) {
if (status[i] != 2 && alpha[i] > highAlpha) highAlpha = alpha[i];
}
// Fill mask of "correct" pixels with 2 on highAlpha pixels
for (int i=0;i<len;i++) {
if (alpha[i] == highAlpha) status[i] = 2;
}
// Alpha finding loop
bool outerLoop = true;
while (outerLoop) {
// Loop through
int totalModified = 0;
bool doRepeat = true;
while (doRepeat) {
int modified = 0;
unsigned char *cur = data;
unsigned char c1,c2,c3;
unsigned char d1,d2,d3;
int error;
for (int i=0;i<len;i++) {
// Get colors
c1 = *(cur++);
c2 = *(cur++);
c3 = *(cur++);
// Check status
if (status[i] != 0) continue;
// Get error
int a = alpha[i];
if (a == 0) error = 255;
else error = 1024/a;
// Right pixel
if (i != len-1 && status[i+1] == 2) {
// Get colors
d1 = *(cur);
d2 = *(cur+1);
d3 = *(cur+2);
// Compare error
if (IN_ERROR_MARGIN(d1,c1,error) && IN_ERROR_MARGIN(d2,c2,error) && IN_ERROR_MARGIN(d3,c3,error)) {
*(cur-3) = d1;
*(cur-2) = d2;
*(cur-1) = d3;
status[i] = 2;
modified++;
continue;
}
}
// Left pixel
if (i != 0 && status[i-1] == 2) {
// Get colors
d1 = *(cur-6);
d2 = *(cur-5);
d3 = *(cur-4);
// Compare error
if (IN_ERROR_MARGIN(d1,c1,error) && IN_ERROR_MARGIN(d2,c2,error) && IN_ERROR_MARGIN(d3,c3,error)) {
*(cur-3) = d1;
*(cur-2) = d2;
*(cur-1) = d3;
status[i] = 2;
modified++;
continue;
}
}
// Top pixel
if (i >= w && status[i-w] == 2) {
// Get colors
d1 = *(cur-w*3-3);
d2 = *(cur-w*3-2);
d3 = *(cur-w*3-1);
// Compare error
if (IN_ERROR_MARGIN(d1,c1,error) && IN_ERROR_MARGIN(d2,c2,error) && IN_ERROR_MARGIN(d3,c3,error)) {
*(cur-3) = d1;
*(cur-2) = d2;
*(cur-1) = d3;
status[i] = 2;
modified++;
continue;
}
}
// Bottom pixel
if (i < len-w && status[i+w] == 2) {
// Get colors
d1 = *(cur+w*3-3);
d2 = *(cur+w*3-2);
d3 = *(cur+w*3-1);
// Compare error
if (IN_ERROR_MARGIN(d1,c1,error) && IN_ERROR_MARGIN(d2,c2,error) && IN_ERROR_MARGIN(d3,c3,error)) {
*(cur-3) = d1;
*(cur-2) = d2;
*(cur-1) = d3;
status[i] = 2;
modified++;
continue;
}
}
}
// End repetion
totalModified += modified;
if (!modified) doRepeat = false;
}
// End outer loop
if (!totalModified) outerLoop = false;
// Copy values 1 to 2
int changes = 0;
for (int i=0;i<len;i++) {
if (status[i] == 1) {
status[i] = 2;
changes++;
}
}
if (!changes) outerLoop = false;
}
// Just for tests, fill alpha with 0xFF
//for (int i=0;i<len;i++) alpha[i] = 0xFF;
// Delete mask
delete [] status;
}
///////////////////////////////////////////////////////////////////////////////////////////////////
// TODO!! MOVE THE TWO FUNCTIONS BELOW INTO A CLASS OF THEIR OWN, THEY MIGHT FIND USE ELSEWHERE. //
// Obvious choice would be the subtitles_rasterizer.h derivation for vsfilter, when that exists. //
///////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////
// Generates a 32-bit wxImage from two frames
// ------------------------------------------
// Frame 1 should have the image on a BLACK background
// Frame 2 should have the same image on a WHITE background
wxImage PRSSubtitleFormat::CalculateAlpha(const unsigned char* frame1, const unsigned char* frame2, int w, int h, int pitch, int *dstx, int *dsty, int *maxalpha) {
// Allocate image data
unsigned char *data = (unsigned char*) malloc(sizeof(unsigned char)*w*h*3);
unsigned char *alpha = (unsigned char*) malloc(sizeof(unsigned char)*w*h);
// Pointers
const unsigned char *src1 = frame1;
const unsigned char *src2 = frame2;
unsigned char *dst = data + ((h-1)*w*3/4);
unsigned char *dsta = alpha + ((h-1)*w/4);
// Boundaries
int minx = w;
int miny = h;
int maxx = 0;
int maxy = 0;
// Process
int maxA = 0;
unsigned char r1,g1,b1,r2,g2,b2;
unsigned char r,g,b,a;
for (int y=h;--y>=0;) {
for (int x=0;x<w;x+=4) {
// Read pixels
b1 = *(src1++);
b2 = *(src2++);
g1 = *(src1++);
g2 = *(src2++);
r1 = *(src1++);
r2 = *(src2++);
src1++;
src2++;
// Calculate new values
a = 255 + r1 - r2;
if (a == 0) {
r = 0;
g = 0;
b = 0;
}
else {
// Update range
if (x < minx) minx = x;
else if (x > maxx) maxx = x;
if (y < miny) miny = y;
else if (y > maxy) maxy = y;
// Calculate colour components
//int mod = MAX(0,128/a-1);
//r = MAX(0,r1-mod)*255 / a;
//g = MAX(0,g1-mod)*255 / a;
//b = MAX(0,b1-mod)*255 / a;
r = r1*255/a;
g = g1*255/a;
b = b1*255/a;
}
// Write to destination
*(dst++) = r;
*(dst++) = g;
*(dst++) = b;
*(dsta++) = a;
// Store maximum alpha
if (a > maxA) maxA = a;
}
// Roll back dst
dst -= w*3/2;
dsta -= w/2;
}
// Store maximum alpha
if (maxalpha) *maxalpha = maxA;
// Calculate sizes
minx /= 4;
maxx /= 4;
if (dstx) *dstx = minx;
if (dsty) *dsty = miny;
int width = maxx-minx+1;
int height = maxy-miny+1;
// 100% transparent image; clean up and return an empty one
if (width <= 0 || height <= 0) {
delete [] data;
delete [] alpha;
return wxImage();
}
// Create the actual image
wxImage img(w/4,h,data,false);
img.SetAlpha(alpha,false);
// Return subimage
wxImage subimg = SubImageWithAlpha(img,wxRect(minx,miny,width,height));
return subimg;
}
////////////////////////////////////////////////
// Creates a sub image preserving alpha channel
// Modified from wx's source
wxImage PRSSubtitleFormat::SubImageWithAlpha (wxImage &source,const wxRect &rect) {
wxImage image;
wxCHECK_MSG(source.Ok(), image, wxT("invalid image") );
wxCHECK_MSG((rect.GetLeft()>=0) && (rect.GetTop()>=0) && (rect.GetRight()<=source.GetWidth()) && (rect.GetBottom()<=source.GetHeight()), image, wxT("invalid subimage size") );
int subwidth=rect.GetWidth();
const int subheight=rect.GetHeight();
image.Create(subwidth, subheight, false);
image.SetAlpha();
unsigned char *subdata = image.GetData();
unsigned char *data = source.GetData();
unsigned char *subalpha = image.GetAlpha();
unsigned char *alpha = source.GetAlpha();
wxCHECK_MSG(subdata, image, wxT("unable to create image"));
const int subleft=3*rect.GetLeft();
const int width=3*source.GetWidth();
const int afullwidth=source.GetWidth();
int awidth = subwidth;
subwidth*=3;
data+=rect.GetTop()*width+subleft;
alpha+=rect.GetTop()*afullwidth+rect.GetLeft();
for (long j = 0; j < subheight; ++j) {
memcpy(subdata, data, subwidth);
memcpy(subalpha, alpha, awidth);
subdata+=subwidth;
subalpha+=awidth;
data+=width;
alpha+=afullwidth;
}
return image;
}
#endif