diff options
Diffstat (limited to 'smelt/sdl/CxImage/ximagif.cpp')
| -rw-r--r-- | smelt/sdl/CxImage/ximagif.cpp | 1681 |
1 files changed, 0 insertions, 1681 deletions
diff --git a/smelt/sdl/CxImage/ximagif.cpp b/smelt/sdl/CxImage/ximagif.cpp deleted file mode 100644 index 8c94b9e..0000000 --- a/smelt/sdl/CxImage/ximagif.cpp +++ /dev/null @@ -1,1681 +0,0 @@ -/*
- * File: ximagif.cpp
- * Purpose: Platform Independent GIF Image Class Loader and Writer
- * 07/Aug/2001 Davide Pizzolato - www.xdp.it
- * CxImage version 7.0.0 31/Dec/2010
- */
-
-#include "ximagif.h"
-
-#if CXIMAGE_SUPPORT_GIF
-
-#include "ximaiter.h"
-
-#if defined (_WIN32_WCE)
- #define assert(s)
-#else
- #include <assert.h>
-#endif
-
-////////////////////////////////////////////////////////////////////////////////
-CxImageGIF::CxImageGIF(): CxImage(CXIMAGE_FORMAT_GIF)
-{
- buf = new uint8_t [GIFBUFTAM + 1];
-
- stack = new uint8_t [MAX_CODES + 1];
- suffix = new uint8_t [MAX_CODES + 1];
- prefix = new uint16_t [MAX_CODES + 1];
-
- htab = new int32_t [HSIZE];
- codetab = new uint16_t [HSIZE];
-
- byte_buff = new uint8_t [257];
- accum = new char [256];
- m_comment = new char [256];
-
- m_loops=0;
- info.dispmeth=0;
- m_comment[0]='\0';
-
-}
-////////////////////////////////////////////////////////////////////////////////
-CxImageGIF::~CxImageGIF()
-{
- delete [] buf;
-
- delete [] stack;
- delete [] suffix;
- delete [] prefix;
-
- delete [] htab;
- delete [] codetab;
-
- delete [] byte_buff;
- delete [] accum;
- delete [] m_comment;
-}
-////////////////////////////////////////////////////////////////////////////////
-#if CXIMAGE_SUPPORT_DECODE
-////////////////////////////////////////////////////////////////////////////////
-bool CxImageGIF::Decode(CxFile *fp)
-{
- /* AD - for transparency */
- struct_dscgif dscgif;
- struct_image image;
- struct_TabCol TabCol;
-
- if (fp == NULL) return false;
-
- fp->Read(&dscgif,/*sizeof(dscgif)*/13,1);
- //if (strncmp(dscgif.header,"GIF8",3)!=0) {
- if (strncmp(dscgif.header,"GIF8",4)!=0) return FALSE;
-
- // Avoid Byte order problem with Mac <AMSN>
- dscgif.scrheight = m_ntohs(dscgif.scrheight);
- dscgif.scrwidth = m_ntohs(dscgif.scrwidth);
-
- if (info.nEscape == -1) {
- // Return output dimensions only
- head.biWidth = dscgif.scrwidth;
- head.biHeight = dscgif.scrheight;
- info.dwType = CXIMAGE_FORMAT_GIF;
- return true;
- }
-
- /* AD - for interlace */
- TabCol.sogct = (int16_t)(1 << ((dscgif.pflds & 0x07)+1));
- TabCol.colres = (int16_t)(((dscgif.pflds & 0x70) >> 4) + 1);
-
- // assume that the image is a truecolor-gif if
- // 1) no global color map found
- // 2) (image.w, image.h) of the 1st image != (dscgif.scrwidth, dscgif.scrheight)
- int32_t bTrueColor=0;
- CxImage* imaRGB=NULL;
-
- // Global colour map?
- if (dscgif.pflds & 0x80)
- fp->Read(TabCol.paleta,sizeof(struct rgb_color)*TabCol.sogct,1);
- else
- bTrueColor++; //first chance for a truecolor gif
-
- int32_t first_transparent_index = 0;
-
- int32_t iImage = 0;
- info.nNumFrames=get_num_frames(fp,&TabCol,&dscgif);
-
- if ((info.nFrame<0)||(info.nFrame>=info.nNumFrames)) return false;
-
- //it cannot be a true color GIF with only one frame
- if (info.nNumFrames == 1)
- bTrueColor=0;
-
- char ch;
- bool bPreviousWasNull = true;
- int32_t prevdispmeth = 0;
- CxImage *previousFrame = NULL;
-
- for (BOOL bContinue = TRUE; bContinue; )
- {
- if (fp->Read(&ch, sizeof(ch), 1) != 1) {break;}
-
- if (info.nEscape > 0) return false; // <vho> - cancel decoding
- if (bPreviousWasNull || ch==0)
- {
- switch (ch)
- {
- case '!': // extension
- {
- bContinue = DecodeExtension(fp);
- break;
- }
- case ',': // image
- {
- assert(sizeof(image) == 9);
- fp->Read(&image,sizeof(image),1);
- //avoid byte order problems with Solaris <candan> <AMSN>
- image.l = m_ntohs(image.l);
- image.t = m_ntohs(image.t);
- image.w = m_ntohs(image.w);
- image.h = m_ntohs(image.h);
-
- if (((image.l + image.w) > dscgif.scrwidth)||((image.t + image.h) > dscgif.scrheight))
- break;
-
- // check if it could be a truecolor gif
- if ((iImage==0) && (image.w != dscgif.scrwidth) && (image.h != dscgif.scrheight))
- bTrueColor++;
-
- rgb_color locpal[256]; //Local Palette
- rgb_color* pcurpal = TabCol.paleta; //Current Palette
- int16_t palcount = TabCol.sogct; //Current Palette color count
-
- // Local colour map?
- if (image.pf & 0x80) {
- palcount = (int16_t)(1 << ((image.pf & 0x07) +1));
- assert(3 == sizeof(struct rgb_color));
- fp->Read(locpal,sizeof(struct rgb_color)*palcount,1);
- pcurpal = locpal;
- }
-
- int32_t bpp; //<DP> select the correct bit per pixel value
- if (palcount <= 2) bpp = 1;
- else if (palcount <= 16) bpp = 4;
- else bpp = 8;
-
- CxImageGIF backimage;
- backimage.CopyInfo(*this);
- if (iImage==0){
- //first frame: build image background
- backimage.Create(dscgif.scrwidth, dscgif.scrheight, bpp, CXIMAGE_FORMAT_GIF);
- first_transparent_index = info.nBkgndIndex;
- backimage.Clear((uint8_t)gifgce.transpcolindex);
- previousFrame = new CxImage(backimage);
- previousFrame->SetRetreiveAllFrames(false);
- } else {
- //generic frame: handle disposal method from previous one
- /*Values : 0 - No disposal specified. The decoder is
- not required to take any action.
- 1 - Do not dispose. The graphic is to be left
- in place.
- 2 - Restore to background color. The area used by the
- graphic must be restored to the background color.
- 3 - Restore to previous. The decoder is required to
- restore the area overwritten by the graphic with
- what was there prior to rendering the graphic.
- */
- /* backimage.Copy(*this);
- if (prevdispmeth==2){
- backimage.Clear((uint8_t)first_transparent_index);
- }*/
- if (prevdispmeth==2){
- backimage.Copy(*this,false,false,false);
- backimage.Clear((uint8_t)first_transparent_index);
- } else if (prevdispmeth==3) {
- backimage.Copy(*this,false,false,false);
- backimage.Create(previousFrame->GetWidth(),
- previousFrame->GetHeight(),
- previousFrame->GetBpp(),CXIMAGE_FORMAT_GIF);
- memcpy(backimage.GetDIB(),previousFrame->GetDIB(),
- backimage.GetSize());
- //backimage.AlphaSet(*previousFrame);
- } else {
- backimage.Copy(*this);
- }
- }
-
- //active frame
- Create(image.w, image.h, bpp, CXIMAGE_FORMAT_GIF);
-
- if ((image.pf & 0x80) || (dscgif.pflds & 0x80)) {
- uint8_t r[256], g[256], b[256];
- int32_t i;//, has_white = 0;
-
- for (i=0; i < palcount; i++) {
- r[i] = pcurpal[i].r;
- g[i] = pcurpal[i].g;
- b[i] = pcurpal[i].b;
- //if (RGB(r[i],g[i],b[i]) == 0xFFFFFF) has_white = 1;
- }
-
- // Force transparency colour white...
- //if (0) if (info.nBkgndIndex >= 0)
- // r[info.nBkgndIndex] = g[info.nBkgndIndex] = b[info.nBkgndIndex] = 255;
- // Fill in with white // AD
- if (info.nBkgndIndex >= 0) {
- while (i < 256) {
- //has_white = 1;
- r[i] = g[i] = b[i] = 255;
- i++;
- }
- }
-
- // Force last colour to white... // AD
- //if ((info.nBkgndIndex >= 0) && !has_white) {
- // r[255] = g[255] = b[255] = 255;
- //}
-
- SetPalette((info.nBkgndIndex >= 0 ? 256 : palcount), r, g, b);
- }
-
- CImageIterator* iter = new CImageIterator(this);
- iter->Upset();
- int32_t badcode=0;
- ibf = GIFBUFTAM+1;
-
- interlaced = image.pf & 0x40;
- iheight = image.h;
- istep = 8;
- iypos = 0;
- ipass = 0;
-
- int32_t pos_start = fp->Tell();
- //if (interlaced) log << "Interlaced" << endl;
- decoder(fp, iter, image.w, badcode);
- delete iter;
-
- if (info.nEscape) return false; // <vho> - cancel decoding
-
- if (bTrueColor<2 ){ //standard GIF: mix frame with background
- backimage.IncreaseBpp(bpp);
- backimage.GifMix(*this,image);
- backimage.SetTransIndex(first_transparent_index);
- backimage.SetPalette(GetPalette());
- Transfer(backimage,false);
- } else { //it's a truecolor gif!
- //force full image decoding
- info.nFrame=info.nNumFrames-1;
- //build the RGB image
- if (imaRGB==NULL) imaRGB = new CxImage(dscgif.scrwidth,dscgif.scrheight,24,CXIMAGE_FORMAT_GIF);
- //copy the partial image into the full RGB image
- for(int32_t y=0;y<image.h;y++){
- for (int32_t x=0;x<image.w;x++){
- imaRGB->SetPixelColor(x+image.l,dscgif.scrheight-1-image.t-y,GetPixelColor(x,image.h-y-1));
- }
- }
- }
-
- prevdispmeth = (gifgce.flags >> 2) & 0x7;
-
- //restore the correct position in the file for the next image
- if (badcode){
- seek_next_image(fp,pos_start);
- } else {
- fp->Seek(-(ibfmax - ibf - 1), SEEK_CUR);
- }
-
- if (info.bGetAllFrames && imaRGB == NULL) {
- if (iImage == 0) {
- DestroyFrames();
- ppFrames = new CxImage*[info.nNumFrames];
- for(int32_t frameIdx = 0; frameIdx < info.nNumFrames; frameIdx++){
- ppFrames[frameIdx] = NULL;
- }
- }
- ppFrames[iImage] = new CxImage(*this);
- ppFrames[iImage]->SetRetreiveAllFrames(false);
- }
- if (prevdispmeth <= 1) {
- delete previousFrame;
- previousFrame = new CxImage(*this);
- previousFrame->SetRetreiveAllFrames(false);
- }
-
- if ((info.nFrame==iImage) && (info.bGetAllFrames==false)) bContinue=false; else iImage++;
-
- break;
- }
- case ';': //terminator
- bContinue=false;
- break;
- default:
- bPreviousWasNull = (ch==0);
- break;
- }
- }
- }
-
- if (bTrueColor>=2 && imaRGB){
- if (gifgce.flags & 0x1){
- imaRGB->SetTransColor(GetPaletteColor((uint8_t)info.nBkgndIndex));
- imaRGB->SetTransIndex(0);
- }
- Transfer(*imaRGB);
- }
- delete imaRGB;
-
- delete previousFrame;
-
- return true;
-
-}
-////////////////////////////////////////////////////////////////////////////////
-bool CxImageGIF::DecodeExtension(CxFile *fp)
-{
- bool bContinue;
- uint8_t count;
- uint8_t fc;
-
- bContinue = (1 == fp->Read(&fc, sizeof(fc), 1));
- if (bContinue) {
- /* AD - for transparency */
- if (fc == 0xF9) {
- bContinue = (1 == fp->Read(&count, sizeof(count), 1));
- if (bContinue) {
- assert(sizeof(gifgce) == 4);
- bContinue = (count == fp->Read(&gifgce, 1, sizeof(gifgce)));
- gifgce.delaytime = m_ntohs(gifgce.delaytime); // Avoid Byte order problem with Mac <AMSN>
- if (bContinue) {
- info.nBkgndIndex = (gifgce.flags & 0x1) ? gifgce.transpcolindex : -1;
- info.dwFrameDelay = gifgce.delaytime;
- SetDisposalMethod((gifgce.flags >> 2) & 0x7);
- } } }
-
- if (fc == 0xFE) { //<DP> Comment block
- bContinue = (1 == fp->Read(&count, sizeof(count), 1));
- if (bContinue) {
- bContinue = (1 == fp->Read(m_comment, count, 1));
- m_comment[count]='\0';
- } }
-
- if (fc == 0xFF) { //<DP> Application Extension block
- bContinue = (1 == fp->Read(&count, sizeof(count), 1));
- if (bContinue) {
- bContinue = (count==11);
- if (bContinue){
- char AppID[11];
- bContinue = (1 == fp->Read(AppID, count, 1));
- if (bContinue) {
- bContinue = (1 == fp->Read(&count, sizeof(count), 1));
- if (bContinue) {
- uint8_t* dati = (uint8_t*)malloc(count);
- bContinue = (dati!=NULL);
- if (bContinue){
- bContinue = (1 == fp->Read(dati, count, 1));
- if (count>2){
- m_loops = dati[1]+256*dati[2];
- }
- }
- free(dati);
- } } } } }
-
- while (bContinue && fp->Read(&count, sizeof(count), 1) && count) {
- //log << "Skipping " << count << " bytes" << endl;
- fp->Seek(count, SEEK_CUR);
- }
- }
- return bContinue;
-
-}
-////////////////////////////////////////////////////////////////////////////////
-#endif //CXIMAGE_SUPPORT_DECODE
-////////////////////////////////////////////////////////////////////////////////
-
-// - This external (machine specific) function is expected to return
-// either the next uint8_t from the GIF file, or a negative error number.
-int32_t CxImageGIF::get_byte(CxFile* file)
-{
- if (ibf>=GIFBUFTAM){
- // FW 06/02/98 >>>
- ibfmax = (int32_t)file->Read( buf , 1 , GIFBUFTAM) ;
- if( ibfmax < GIFBUFTAM ) buf[ ibfmax ] = 255 ;
- // FW 06/02/98 <<<
- ibf = 0;
- }
- if (ibf>=ibfmax) return -1; //<DP> avoid overflows
- return buf[ibf++];
-}
-////////////////////////////////////////////////////////////////////////////////
-/* - This function takes a full line of pixels (one uint8_t per pixel) and
- * displays them (or does whatever your program wants with them...). It
- * should return zero, or negative if an error or some other event occurs
- * which would require aborting the decode process... Note that the length
- * passed will almost always be equal to the line length passed to the
- * decoder function, with the sole exception occurring when an ending code
- * occurs in an odd place in the GIF file... In any case, linelen will be
- * equal to the number of pixels passed...
-*/
-int32_t CxImageGIF::out_line(CImageIterator* iter, uint8_t *pixels, int32_t linelen)
-{
- if (iter == NULL || pixels == NULL)
- return -1;
-
- //<DP> for 1 & 4 bpp images, the pixels are compressed
- if (head.biBitCount < 8){
- for(int32_t x=0;x<head.biWidth;x++){
- uint8_t pos;
- uint8_t* iDst= pixels + (x*head.biBitCount >> 3);
- if (head.biBitCount==4){
- pos = (uint8_t)(4*(1-x%2));
- *iDst &= ~(0x0F<<pos);
- *iDst |= ((pixels[x] & 0x0F)<<pos);
- } else if (head.biBitCount==1){
- pos = (uint8_t)(7-x%8);
- *iDst &= ~(0x01<<pos);
- *iDst |= ((pixels[x] & 0x01)<<pos);
- }
- }
- }
-
- /* AD - for interlace */
- if (interlaced) {
- iter->SetY(iheight-iypos-1);
- iter->SetRow(pixels, linelen);
-
- if ((iypos += istep) >= iheight) {
- do {
- if (ipass++ > 0) istep /= 2;
- iypos = istep / 2;
- }
- while (iypos > iheight);
- }
- return 0;
- } else {
- if (iter->ItOK()) {
- iter->SetRow(pixels, linelen);
- (void)iter->PrevRow();
- return 0;
- } else {
- // puts("chafeo");
- return -1;
- }
- }
-}
-////////////////////////////////////////////////////////////////////////////////
-#if CXIMAGE_SUPPORT_ENCODE
-////////////////////////////////////////////////////////////////////////////////
-// SaveFile - writes GIF87a gif file
-// Randy Spann 6/15/97
-// R.Spann@ConnRiver.net
-bool CxImageGIF::Encode(CxFile * fp)
-{
- if (EncodeSafeCheck(fp)) return false;
-
- if(head.biBitCount > 8) {
- //strcpy(info.szLastError,"GIF Images must be 8 bit or less");
- //return FALSE;
- return EncodeRGB(fp);
- }
-
- if ( GetNumFrames()>1 && ppFrames ) {
- return Encode(fp, ppFrames, GetNumFrames() );
- }
-
- EncodeHeader(fp);
-
- EncodeExtension(fp);
-
- EncodeComment(fp);
-
- EncodeBody(fp);
-
- fp->PutC(';'); // Write the GIF file terminator
-
- return true; // done!
-}
-////////////////////////////////////////////////////////////////////////////////
-bool CxImageGIF::Encode(CxFile * fp, CxImage ** pImages, int32_t pagecount, bool bLocalColorMap, bool bLocalDispMeth)
-{
- cx_try {
- if (fp==NULL) cx_throw("invalid file pointer");
- if (pImages==NULL || pagecount<=0 || pImages[0]==NULL) cx_throw("multipage GIF, no images!");
-
- int32_t i;
- for (i=0; i<pagecount; i++){
- if (pImages[i]==NULL)
- cx_throw("Bad image pointer");
- if (!(pImages[i]->IsValid()))
- cx_throw("Empty image");
- if (pImages[i]->GetNumColors()==0)
- cx_throw("CxImageGIF::Encode cannot create animated GIFs with a true color frame. Use DecreaseBpp before");
- }
-
- CxImageGIF ghost;
-
- //write the first image
- ghost.Ghost(pImages[0]);
- ghost.EncodeHeader(fp);
-
- if (m_loops!=1){
- ghost.SetLoops(max(0,m_loops-1));
- ghost.EncodeLoopExtension(fp);
- }
-
- if (bLocalDispMeth) {
- ghost.EncodeExtension(fp);
- } else {
- uint8_t dm = ghost.GetDisposalMethod();
- ghost.SetDisposalMethod(GetDisposalMethod());
- ghost.EncodeExtension(fp);
- ghost.SetDisposalMethod(dm);
- }
-
- EncodeComment(fp);
-
- ghost.EncodeBody(fp);
-
- for (i=1; i<pagecount; i++){
- ghost.Ghost(pImages[i]);
-
- if (bLocalDispMeth) {
- ghost.EncodeExtension(fp);
- } else {
- uint8_t dm = ghost.GetDisposalMethod();
- ghost.SetDisposalMethod(GetDisposalMethod());
- ghost.EncodeExtension(fp);
- ghost.SetDisposalMethod(dm);
- }
-
- ghost.EncodeBody(fp,bLocalColorMap);
- }
-
- fp->PutC(';'); // Write the GIF file terminator
-
- } cx_catch {
- if (strcmp(message,"")) strncpy(info.szLastError,message,255);
- return false;
- }
- return true;
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::EncodeHeader(CxFile *fp)
-{
- fp->Write("GIF89a",1,6); //GIF Header
-
- Putword(head.biWidth,fp); //Logical screen descriptor
- Putword(head.biHeight,fp);
-
- uint8_t Flags;
- if (head.biClrUsed==0){
- Flags=0x11;
- } else {
- Flags = 0x80;
- Flags |=(head.biBitCount - 1) << 5;
- Flags |=(head.biBitCount - 1);
- }
-
- fp->PutC(Flags); //GIF "packed fields"
- fp->PutC(0); //GIF "BackGround"
- fp->PutC(0); //GIF "pixel aspect ratio"
-
- if (head.biClrUsed!=0){
- RGBQUAD* pPal = GetPalette();
- for(uint32_t i=0; i<head.biClrUsed; ++i)
- {
- fp->PutC(pPal[i].rgbRed);
- fp->PutC(pPal[i].rgbGreen);
- fp->PutC(pPal[i].rgbBlue);
- }
- }
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::EncodeExtension(CxFile *fp)
-{
- // TRK BEGIN : transparency
- fp->PutC('!');
- fp->PutC(TRANSPARENCY_CODE);
-
- gifgce.flags = 0;
- gifgce.flags |= ((info.nBkgndIndex != -1) ? 1 : 0);
- gifgce.flags |= ((GetDisposalMethod() & 0x7) << 2);
- gifgce.delaytime = (uint16_t)info.dwFrameDelay;
- gifgce.transpcolindex = (uint8_t)info.nBkgndIndex;
-
- //Invert byte order in case we use a byte order arch, then set it back <AMSN>
- gifgce.delaytime = m_ntohs(gifgce.delaytime);
- fp->PutC(sizeof(gifgce));
- fp->Write(&gifgce, sizeof(gifgce), 1);
- gifgce.delaytime = m_ntohs(gifgce.delaytime);
-
- fp->PutC(0);
- // TRK END
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::EncodeLoopExtension(CxFile *fp)
-{
- fp->PutC('!'); //byte 1 : 33 (hex 0x21) GIF Extension code
- fp->PutC(255); //byte 2 : 255 (hex 0xFF) Application Extension Label
- fp->PutC(11); //byte 3 : 11 (hex (0x0B) Length of Application Block (eleven bytes of data to follow)
- fp->Write("NETSCAPE2.0",11,1);
- fp->PutC(3); //byte 15 : 3 (hex 0x03) Length of Data Sub-Block (three bytes of data to follow)
- fp->PutC(1); //byte 16 : 1 (hex 0x01)
- Putword(m_loops,fp); //bytes 17 to 18 : 0 to 65535, an unsigned integer in lo-hi byte format.
- //This indicate the number of iterations the loop should be executed.
- fp->PutC(0); //bytes 19 : 0 (hex 0x00) a Data Sub-block Terminator.
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::EncodeBody(CxFile *fp, bool bLocalColorMap)
-{
- curx = 0;
- cury = head.biHeight - 1; //because we read the image bottom to top
- CountDown = (int32_t)head.biWidth * (int32_t)head.biHeight;
-
- fp->PutC(',');
-
- Putword(info.xOffset,fp);
- Putword(info.yOffset,fp);
- Putword(head.biWidth,fp);
- Putword(head.biHeight,fp);
-
- uint8_t Flags=0x00; //non-interlaced (0x40 = interlaced) (0x80 = LocalColorMap)
- if (bLocalColorMap) { Flags|=0x80; Flags|=head.biBitCount-1; }
- fp->PutC(Flags);
-
- if (bLocalColorMap){
- Flags|=0x87;
- RGBQUAD* pPal = GetPalette();
- for(uint32_t i=0; i<head.biClrUsed; ++i)
- {
- fp->PutC(pPal[i].rgbRed);
- fp->PutC(pPal[i].rgbGreen);
- fp->PutC(pPal[i].rgbBlue);
- }
- }
-
- int32_t InitCodeSize = head.biBitCount <=1 ? 2 : head.biBitCount;
- // Write out the initial code size
- fp->PutC((uint8_t)InitCodeSize);
-
- // Go and actually compress the data
- switch (GetCodecOption(CXIMAGE_FORMAT_GIF))
- {
- case 1: //uncompressed
- compressNONE(InitCodeSize+1, fp);
- break;
- case 2: //RLE
- compressRLE(InitCodeSize+1, fp);
- break;
- default: //LZW
- compressLZW(InitCodeSize+1, fp);
- }
-
- // Write out a Zero-length packet (to end the series)
- fp->PutC(0);
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::EncodeComment(CxFile *fp)
-{
- uint32_t n = (uint32_t) strlen(m_comment);
- if (n>255) n=255;
- if (n) {
- fp->PutC('!'); //extension code:
- fp->PutC(254); //comment extension
- fp->PutC((uint8_t)n); //size of comment
- fp->Write(m_comment,n,1);
- fp->PutC(0); //block terminator
- }
-}
-////////////////////////////////////////////////////////////////////////////////
-bool CxImageGIF::EncodeRGB(CxFile *fp)
-{
- EncodeHeader(fp);
-
-// EncodeLoopExtension(fp);
-
- EncodeComment(fp);
-
- uint32_t w,h;
- w=h=0;
- const int32_t cellw = 17;
- const int32_t cellh = 15;
- CxImageGIF tmp;
- for (int32_t y=0;y<head.biHeight;y+=cellh){
- for (int32_t x=0;x<head.biWidth;x+=cellw){
- if ((head.biWidth -x)<cellw) w=head.biWidth -x; else w=cellw;
- if ((head.biHeight-y)<cellh) h=head.biHeight-y; else h=cellh;
-
- if (w!=tmp.GetWidth() || h!=tmp.GetHeight()) tmp.Create(w,h,8);
-
- if (IsTransparent()){
- tmp.SetTransIndex(0);
- tmp.SetPaletteColor(0,GetTransColor());
- }
-
- uint8_t i;
- for (uint32_t j=0;j<h;j++){
- for (uint32_t k=0;k<w;k++){
- i=(uint8_t)(1+k+cellw*j);
- tmp.SetPaletteColor(i,GetPixelColor(x+k,head.biHeight-y-h+j));
- tmp.SetPixelIndex(k,j,tmp.GetNearestIndex(tmp.GetPaletteColor(i)));
- }
- }
-
- tmp.SetOffset(x,y);
- tmp.EncodeExtension(fp);
- tmp.EncodeBody(fp,true);
- }
- }
-
- fp->PutC(';'); // Write the GIF file terminator
-
- return true; // done!
-}
-////////////////////////////////////////////////////////////////////////////////
-#endif // CXIMAGE_SUPPORT_ENCODE
-////////////////////////////////////////////////////////////////////////////////
-// Return the next pixel from the image
-// <DP> fix for 1 & 4 bpp images
-int32_t CxImageGIF::GifNextPixel( )
-{
- if( CountDown == 0 ) return EOF;
- --CountDown;
- int32_t r = GetPixelIndex(curx,cury);
- // Bump the current X position
- ++curx;
- if( curx == head.biWidth ){
- curx = 0;
- cury--; //bottom to top
- }
- return r;
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::Putword(int32_t w, CxFile *fp )
-{
- fp->PutC((uint8_t)(w & 0xff));
- fp->PutC((uint8_t)((w >> 8) & 0xff));
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::compressNONE( int32_t init_bits, CxFile* outfile)
-{
- register int32_t c;
- register int32_t ent;
-
- // g_init_bits - initial number of bits
- // g_outfile - pointer to output file
- g_init_bits = init_bits;
- g_outfile = outfile;
-
- // Set up the necessary values
- cur_accum = cur_bits = clear_flg = 0;
- maxcode = (int16_t)MAXCODE(n_bits = g_init_bits);
- code_int maxmaxcode = (code_int)1 << MAXBITSCODES;
-
- ClearCode = (1 << (init_bits - 1));
- EOFCode = ClearCode + 1;
- free_ent = (int16_t)(ClearCode + 2);
-
- a_count=0;
- ent = GifNextPixel( );
-
- output( (code_int)ClearCode );
-
- while ( ent != EOF ) {
- c = GifNextPixel();
-
- output ( (code_int) ent );
- ent = c;
- if ( free_ent < maxmaxcode ) {
- free_ent++;
- } else {
- free_ent=(int16_t)(ClearCode+2);
- clear_flg=1;
- output((code_int)ClearCode);
- }
- }
- // Put out the final code.
- output( (code_int) EOFCode );
-}
-////////////////////////////////////////////////////////////////////////////////
-
-/***************************************************************************
- *
- * GIFCOMPR.C - LZW GIF Image compression routines
- *
- ***************************************************************************/
-
-void CxImageGIF::compressLZW( int32_t init_bits, CxFile* outfile)
-{
- register int32_t fcode;
- register int32_t c;
- register int32_t ent;
- register int32_t hshift;
- register int32_t disp;
- register int32_t i;
-
- // g_init_bits - initial number of bits
- // g_outfile - pointer to output file
- g_init_bits = init_bits;
- g_outfile = outfile;
-
- // Set up the necessary values
- cur_accum = cur_bits = clear_flg = 0;
- maxcode = (int16_t)MAXCODE(n_bits = g_init_bits);
- code_int maxmaxcode = (code_int)1 << MAXBITSCODES;
-
- ClearCode = (1 << (init_bits - 1));
- EOFCode = ClearCode + 1;
- free_ent = (int16_t)(ClearCode + 2);
-
- a_count=0;
- ent = GifNextPixel( );
-
- hshift = 0;
- for ( fcode = (int32_t) HSIZE; fcode < 65536L; fcode *= 2L ) ++hshift;
- hshift = 8 - hshift; /* set hash code range bound */
- cl_hash((int32_t)HSIZE); /* clear hash table */
- output( (code_int)ClearCode );
-
- while ( (c = GifNextPixel( )) != EOF ) {
-
- fcode = (int32_t) (((int32_t) c << MAXBITSCODES) + ent);
- i = (((code_int)c << hshift) ^ ent); /* xor hashing */
-
- if ( HashTabOf (i) == fcode ) {
- ent = CodeTabOf (i);
- continue;
- } else if ( (int32_t)HashTabOf (i) < 0 ) /* empty slot */
- goto nomatch;
- disp = HSIZE - i; /* secondary hash (after G. Knott) */
- if ( i == 0 ) disp = 1;
-probe:
- if ( (i -= disp) < 0 ) i += HSIZE;
- if ( HashTabOf (i) == fcode ) { ent = CodeTabOf (i); continue; }
- if ( (int32_t)HashTabOf (i) > 0 ) goto probe;
-nomatch:
- output ( (code_int) ent );
- ent = c;
- if ( free_ent < maxmaxcode ) {
- CodeTabOf (i) = free_ent++; /* code -> hashtable */
- HashTabOf (i) = fcode;
- } else {
- cl_hash((int32_t)HSIZE);
- free_ent=(int16_t)(ClearCode+2);
- clear_flg=1;
- output((code_int)ClearCode);
- }
- }
- // Put out the final code.
- output( (code_int)ent );
- output( (code_int) EOFCode );
-}
-////////////////////////////////////////////////////////////////////////////////
-
-static const uint32_t code_mask[] = { 0x0000, 0x0001, 0x0003, 0x0007, 0x000F,
- 0x001F, 0x003F, 0x007F, 0x00FF,
- 0x01FF, 0x03FF, 0x07FF, 0x0FFF,
- 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF };
-
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::output( code_int code)
-{
- cur_accum &= code_mask[ cur_bits ];
-
- if( cur_bits > 0 )
- cur_accum |= ((int32_t)code << cur_bits);
- else
- cur_accum = code;
-
- cur_bits += n_bits;
-
- while( cur_bits >= 8 ) {
- char_out( (uint32_t)(cur_accum & 0xff) );
- cur_accum >>= 8;
- cur_bits -= 8;
- }
-
- /*
- * If the next entry is going to be too big for the code size,
- * then increase it, if possible.
- */
-
- if ( free_ent > maxcode || clear_flg ) {
- if( clear_flg ) {
- maxcode = (int16_t)MAXCODE(n_bits = g_init_bits);
- clear_flg = 0;
- } else {
- ++n_bits;
- if ( n_bits == MAXBITSCODES )
- maxcode = (code_int)1 << MAXBITSCODES; /* should NEVER generate this code */
- else
- maxcode = (int16_t)MAXCODE(n_bits);
- }
- }
-
- if( code == EOFCode ) {
- // At EOF, write the rest of the buffer.
- while( cur_bits > 0 ) {
- char_out( (uint32_t)(cur_accum & 0xff) );
- cur_accum >>= 8;
- cur_bits -= 8;
- }
-
- flush_char();
- g_outfile->Flush();
-
- if(g_outfile->Error()) strcpy(info.szLastError,"Write Error in GIF file");
- }
-}
-////////////////////////////////////////////////////////////////////////////////
-
-void CxImageGIF::cl_hash(int32_t hsize)
-
-{
- register int32_t *htab_p = htab+hsize;
-
- register int32_t i;
- register int32_t m1 = -1L;
-
- i = hsize - 16;
-
- do {
- *(htab_p-16)=m1;
- *(htab_p-15)=m1;
- *(htab_p-14)=m1;
- *(htab_p-13)=m1;
- *(htab_p-12)=m1;
- *(htab_p-11)=m1;
- *(htab_p-10)=m1;
- *(htab_p-9)=m1;
- *(htab_p-8)=m1;
- *(htab_p-7)=m1;
- *(htab_p-6)=m1;
- *(htab_p-5)=m1;
- *(htab_p-4)=m1;
- *(htab_p-3)=m1;
- *(htab_p-2)=m1;
- *(htab_p-1)=m1;
-
- htab_p-=16;
- } while ((i-=16) >=0);
-
- for (i+=16;i>0;--i)
- *--htab_p=m1;
-}
-
-/*******************************************************************************
-* GIF specific
-*******************************************************************************/
-
-void CxImageGIF::char_out(int32_t c)
-{
- accum[a_count++]=(char)c;
- if (a_count >=254)
- flush_char();
-}
-
-void CxImageGIF::flush_char()
-{
- if (a_count > 0) {
- g_outfile->PutC((uint8_t)a_count);
- g_outfile->Write(accum,1,a_count);
- a_count=0;
- }
-}
-
-/*******************************************************************************
-* GIF decoder
-*******************************************************************************/
-/* DECODE.C - An LZW decoder for GIF
- * Copyright (C) 1987, by Steven A. Bennett
- * Copyright (C) 1994, C++ version by Alejandro Aguilar Sierra
-*
- * Permission is given by the author to freely redistribute and include
- * this code in any program as int32_t as this credit is given where due.
- *
- * In accordance with the above, I want to credit Steve Wilhite who wrote
- * the code which this is heavily inspired by...
- *
- * GIF and 'Graphics Interchange Format' are trademarks (tm) of
- * Compuserve, Incorporated, an H&R Block Company.
- *
- * Release Notes: This file contains a decoder routine for GIF images
- * which is similar, structurally, to the original routine by Steve Wilhite.
- * It is, however, somewhat noticably faster in most cases.
- *
- */
-
-////////////////////////////////////////////////////////////////////////////////
-
-int16_t CxImageGIF::init_exp(int16_t size)
-{
- curr_size = (int16_t)(size + 1);
- top_slot = (int16_t)(1 << curr_size);
- clear = (int16_t)(1 << size);
- ending = (int16_t)(clear + 1);
- slot = newcodes = (int16_t)(ending + 1);
- navail_bytes = nbits_left = 0;
-
- memset(stack,0,MAX_CODES + 1);
- memset(prefix,0,MAX_CODES + 1);
- memset(suffix,0,MAX_CODES + 1);
- return(0);
-}
-////////////////////////////////////////////////////////////////////////////////
-
-/* get_next_code()
- * - gets the next code from the GIF file. Returns the code, or else
- * a negative number in case of file errors...
- */
-int16_t CxImageGIF::get_next_code(CxFile* file)
-{
- int16_t i, x;
- uint32_t ret;
-
- if (nbits_left == 0) {
- if (navail_bytes <= 0) {
- /* Out of bytes in current block, so read next block */
- pbytes = byte_buff;
- if ((navail_bytes = (int16_t)get_byte(file)) < 0)
- return(navail_bytes);
- else if (navail_bytes) {
- for (i = 0; i < navail_bytes; ++i) {
- if ((x = (int16_t)get_byte(file)) < 0) return(x);
- byte_buff[i] = (uint8_t)x;
- }
- }
- }
- b1 = *pbytes++;
- nbits_left = 8;
- --navail_bytes;
- }
-
- if (navail_bytes<0) return ending; // prevent deadlocks (thanks to Mike Melnikov)
-
- ret = b1 >> (8 - nbits_left);
- while (curr_size > nbits_left){
- if (navail_bytes <= 0){
- /* Out of bytes in current block, so read next block*/
- pbytes = byte_buff;
- if ((navail_bytes = (int16_t)get_byte(file)) < 0)
- return(navail_bytes);
- else if (navail_bytes){
- for (i = 0; i < navail_bytes; ++i){
- if ((x = (int16_t)get_byte(file)) < 0) return(x);
- byte_buff[i] = (uint8_t)x;
- }
- }
- }
- b1 = *pbytes++;
- ret |= b1 << nbits_left;
- nbits_left += 8;
- --navail_bytes;
- }
- nbits_left = (int16_t)(nbits_left-curr_size);
- ret &= code_mask[curr_size];
- return((int16_t)(ret));
-}
-////////////////////////////////////////////////////////////////////////////////
-
-/* int16_t decoder(linewidth)
- * int16_t linewidth; * Pixels per line of image *
- *
- * - This function decodes an LZW image, according to the method used
- * in the GIF spec. Every *linewidth* "characters" (ie. pixels) decoded
- * will generate a call to out_line(), which is a user specific function
- * to display a line of pixels. The function gets it's codes from
- * get_next_code() which is responsible for reading blocks of data and
- * seperating them into the proper size codes. Finally, get_byte() is
- * the global routine to read the next uint8_t from the GIF file.
- *
- * It is generally a good idea to have linewidth correspond to the actual
- * width of a line (as specified in the Image header) to make your own
- * code a bit simpler, but it isn't absolutely necessary.
- *
- * Returns: 0 if successful, else negative. (See ERRS.H)
- *
- */
-/* bad_code_count is incremented each time an out of range code is read.
- * When this value is non-zero after a decode, your GIF file is probably
- * corrupt in some way...
- */
-int16_t CxImageGIF::decoder(CxFile* file, CImageIterator* iter, int16_t linewidth, int32_t &bad_code_count)
-{
- register uint8_t *sp, *bufptr;
- uint8_t *buf;
- register int16_t code, fc, oc, bufcnt;
- int16_t c, size, ret;
-
- if (linewidth<=0)
- return BAD_LINE_WIDTH;
-
- /* Initialize for decoding a new image... */
- bad_code_count = 0;
- if ((size = (int16_t)get_byte(file)) < 0) return(size);
- if (size < 2 || 9 < size) return(BAD_CODE_SIZE);
- // out_line = outline;
- init_exp(size);
- //printf("L %d %x\n",linewidth,size);
-
- /* Initialize in case they forgot to put in a clear code.
- * (This shouldn't happen, but we'll try and decode it anyway...)
- */
- oc = fc = 0;
-
- /* Allocate space for the decode buffer */
- if ((buf = new uint8_t[linewidth + 1]) == NULL) return(OUT_OF_MEMORY);
-
- /* Set up the stack pointer and decode buffer pointer */
- sp = stack;
- bufptr = buf;
- bufcnt = linewidth;
-
- /* This is the main loop. For each code we get we pass through the
- * linked list of prefix codes, pushing the corresponding "character" for
- * each code onto the stack. When the list reaches a single "character"
- * we push that on the stack too, and then start unstacking each
- * character for output in the correct order. Special handling is
- * included for the clear code, and the whole thing ends when we get
- * an ending code.
- */
- while ((c = get_next_code(file)) != ending) {
- /* If we had a file error, return without completing the decode*/
- if (c < 0){
- delete [] buf;
- return(0);
- }
- /* If the code is a clear code, reinitialize all necessary items.*/
- if (c == clear){
- curr_size = (int16_t)(size + 1);
- slot = newcodes;
- top_slot = (int16_t)(1 << curr_size);
-
- /* Continue reading codes until we get a non-clear code
- * (Another unlikely, but possible case...)
- */
- while ((c = get_next_code(file)) == clear);
-
- /* If we get an ending code immediately after a clear code
- * (Yet another unlikely case), then break out of the loop.
- */
- if (c == ending) break;
-
- /* Finally, if the code is beyond the range of already set codes,
- * (This one had better NOT happen... I have no idea what will
- * result from this, but I doubt it will look good...) then set it
- * to color zero.
- */
- if (c >= slot) c = 0;
- oc = fc = c;
-
- /* And let us not forget to put the char into the buffer... And
- * if, on the off chance, we were exactly one pixel from the end
- * of the line, we have to send the buffer to the out_line()
- * routine...
- */
- *bufptr++ = (uint8_t)c;
- if (--bufcnt == 0) {
- if (iter) {
- if ((ret = (int16_t)out_line(iter, buf, linewidth)) < 0) {
- delete [] buf;
- return(ret);
- }
- }
- bufptr = buf;
- bufcnt = linewidth;
- }
- } else {
- /* In this case, it's not a clear code or an ending code, so
- * it must be a code code... So we can now decode the code into
- * a stack of character codes. (Clear as mud, right?)
- */
- code = c;
-
- /* Here we go again with one of those off chances... If, on the
- * off chance, the code we got is beyond the range of those already
- * set up (Another thing which had better NOT happen...) we trick
- * the decoder into thinking it actually got the last code read.
- * (Hmmn... I'm not sure why this works... But it does...)
- */
- if (code >= slot && sp<(stack+MAX_CODES-1)) {
- if (code > slot)
- ++bad_code_count;
- code = oc;
- *sp++ = (uint8_t)fc;
- }
-
- /* Here we scan back along the linked list of prefixes, pushing
- * helpless characters (ie. suffixes) onto the stack as we do so.
- */
- while (code >= newcodes && sp<(stack+MAX_CODES-1)) {
- *sp++ = suffix[code];
- code = prefix[code];
- }
-
- /* Push the last character on the stack, and set up the new
- * prefix and suffix, and if the required slot number is greater
- * than that allowed by the current bit size, increase the bit
- * size. (NOTE - If we are all full, we *don't* save the new
- * suffix and prefix... I'm not certain if this is correct...
- * it might be more proper to overwrite the last code...
- */
- *sp++ = (uint8_t)code;
- if (slot < top_slot){
- suffix[slot] = (uint8_t)(fc = (uint8_t)code);
- prefix[slot++] = oc;
- oc = c;
- }
- if (slot >= top_slot){
- if (curr_size < 12) {
- top_slot <<= 1;
- ++curr_size;
- }
- }
-
- /* Now that we've pushed the decoded string (in reverse order)
- * onto the stack, lets pop it off and put it into our decode
- * buffer... And when the decode buffer is full, write another
- * line...
- */
- while (sp > stack) {
- *bufptr++ = *(--sp);
- if (--bufcnt == 0) {
- if (iter) {
- if ((ret = (int16_t)out_line(iter, buf, linewidth)) < 0) {
- delete [] buf;
- return(ret);
- }
- }
- bufptr = buf;
- bufcnt = linewidth;
- }
- }
- }
- }
- ret = 0;
- if (bufcnt != linewidth && iter)
- ret = (int16_t)out_line(iter, buf, (linewidth - bufcnt));
- delete [] buf;
- return(ret);
-}
-////////////////////////////////////////////////////////////////////////////////
-int32_t CxImageGIF::get_num_frames(CxFile *fp,struct_TabCol* TabColSrc,struct_dscgif* dscgif)
-{
- struct_image image;
-
- int32_t pos=fp->Tell();
- int32_t nframes=0;
-
- struct_TabCol TempTabCol;
- memcpy(&TempTabCol,TabColSrc,sizeof(struct_TabCol));
-
- char ch;
- bool bPreviousWasNull = true;
-
- for (BOOL bContinue = TRUE; bContinue; )
- {
- if (fp->Read(&ch, sizeof(ch), 1) != 1) {break;}
-
- if (bPreviousWasNull || ch==0)
- {
- switch (ch)
- {
- case '!': // extension
- {
- DecodeExtension(fp);
- break;
- }
- case ',': // image
- {
-
- assert(sizeof(image) == 9);
- //log << "Image header" << endl;
- fp->Read(&image,sizeof(image),1);
-
- //avoid byte order problems with Solaris <candan> <AMSN>
- image.l = m_ntohs(image.l);
- image.t = m_ntohs(image.t);
- image.w = m_ntohs(image.w);
- image.h = m_ntohs(image.h);
-
- // in case of images with empty screen descriptor, give a last chance
- if (dscgif->scrwidth==0 && dscgif->scrheight==0){
- dscgif->scrwidth = image.w;
- dscgif->scrheight = image.h;
- }
-
- if (((image.l + image.w) > dscgif->scrwidth)||((image.t + image.h) > dscgif->scrheight))
- break;
-
- nframes++;
-
- // Local colour map?
- if (image.pf & 0x80) {
- TempTabCol.sogct = (int16_t)(1 << ((image.pf & 0x07) +1));
- assert(3 == sizeof(struct rgb_color));
- fp->Read(TempTabCol.paleta,sizeof(struct rgb_color)*TempTabCol.sogct,1);
- //log << "Local colour map" << endl;
- }
-
- int32_t badcode=0;
- ibf = GIFBUFTAM+1;
-
- interlaced = image.pf & 0x40;
- iheight = image.h;
- istep = 8;
- iypos = 0;
- ipass = 0;
-
- int32_t pos_start = fp->Tell();
-
- //if (interlaced) log << "Interlaced" << endl;
- decoder(fp, 0, image.w, badcode);
-
- if (badcode){
- seek_next_image(fp,pos_start);
- } else {
- fp->Seek(-(ibfmax - ibf - 1), SEEK_CUR);
- }
-
- break;
- }
- case ';': //terminator
- bContinue=false;
- break;
- default:
- bPreviousWasNull = (ch==0);
- break;
- }
- }
- }
-
- fp->Seek(pos,SEEK_SET);
- return nframes;
-}
-////////////////////////////////////////////////////////////////////////////////
-int32_t CxImageGIF::seek_next_image(CxFile* fp, int32_t position)
-{
- fp->Seek(position, SEEK_SET);
- char ch1,ch2;
- ch1=ch2=0;
- while(fp->Read(&ch2,sizeof(char),1)>0){
- if (ch1 == 0 && ch2 == ','){
- fp->Seek(-1,SEEK_CUR);
- return fp->Tell();
- } else {
- ch1 = ch2;
- }
- }
- return -1;
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::SetLoops(int32_t loops)
-{ m_loops=loops; }
-////////////////////////////////////////////////////////////////////////////////
-int32_t CxImageGIF::GetLoops()
-{ return m_loops; }
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::SetComment(const char* sz_comment_in)
-{ if (sz_comment_in) strncpy(m_comment,sz_comment_in,255); }
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::GetComment(char* sz_comment_out)
-{ if (sz_comment_out) strncpy(sz_comment_out,m_comment,255); }
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::GifMix(CxImage & imgsrc2, struct_image & imgdesc)
-{
- int32_t ymin = max(0,(int32_t)(GetHeight()-imgdesc.t - imgdesc.h));
- int32_t ymax = GetHeight()-imgdesc.t;
- int32_t xmin = imgdesc.l;
- int32_t xmax = min(GetWidth(), (uint32_t)(imgdesc.l + imgdesc.w));
-
- int32_t ibg2= imgsrc2.GetTransIndex();
- uint8_t i2;
-
- for(int32_t y = ymin; y < ymax; y++){
- for(int32_t x = xmin; x < xmax; x++){
- i2 = imgsrc2.GetPixelIndex(x-xmin,y-ymin);
- if(i2!=ibg2) SetPixelIndex(x,y,i2);
- }
- }
-}
-////////////////////////////////////////////////////////////////////////////////
-/*-----------------------------------------------------------------------
- *
- * miGIF Compression - mouse and ivo's GIF-compatible compression
- *
- * -run length encoding compression routines-
- *
- * Copyright (C) 1998 Hutchison Avenue Software Corporation
- * http://www.hasc.com
- * info@hasc.com
- *
- * Permission to use, copy, modify, and distribute this software and its
- * documentation for any purpose and without fee is hereby granted, provided
- * that the above copyright notice appear in all copies and that both that
- * copyright notice and this permission notice appear in supporting
- * documentation. This software is provided "AS IS." The Hutchison Avenue
- * Software Corporation disclaims all warranties, either express or implied,
- * including but not limited to implied warranties of merchantability and
- * fitness for a particular purpose, with respect to this code and accompanying
- * documentation.
- *
- * The miGIF compression routines do not, strictly speaking, generate files
- * conforming to the GIF spec, since the image data is not LZW-compressed
- * (this is the point: in order to avoid transgression of the Unisys patent
- * on the LZW algorithm.) However, miGIF generates data streams that any
- * reasonably sane LZW decompresser will decompress to what we want.
- *
- * miGIF compression uses run length encoding. It compresses horizontal runs
- * of pixels of the same color. This type of compression gives good results
- * on images with many runs, for example images with lines, text and solid
- * shapes on a solid-colored background. It gives little or no compression
- * on images with few runs, for example digital or scanned photos.
- *
- * der Mouse
- * mouse@rodents.montreal.qc.ca
- * 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B
- *
- * ivo@hasc.com
- *
- * The Graphics Interchange Format(c) is the Copyright property of
- * CompuServe Incorporated. GIF(sm) is a Service Mark property of
- * CompuServe Incorporated.
- *
- */
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::rle_clear(struct_RLE* rle)
-{
- rle->out_bits = rle->out_bits_init;
- rle->out_bump = rle->out_bump_init;
- rle->out_clear = rle->out_clear_init;
- rle->out_count = 0;
- rle->rl_table_max = 0;
- rle->just_cleared = 1;
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::rle_flush(struct_RLE* rle)
-{
- if (rle->rl_count == 1){
- rle_output_plain(rle->rl_pixel,rle);
- rle->rl_count = 0;
- return;
- }
- if (rle->just_cleared){
- rle_flush_fromclear(rle->rl_count,rle);
- } else if ((rle->rl_table_max < 2) || (rle->rl_table_pixel != rle->rl_pixel)) {
- rle_flush_clearorrep(rle->rl_count,rle);
- } else {
- rle_flush_withtable(rle->rl_count,rle);
- }
- rle->rl_count = 0;
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::rle_output_plain(int32_t c,struct_RLE* rle)
-{
- rle->just_cleared = 0;
- rle_output(c,rle);
- rle->out_count++;
- if (rle->out_count >= rle->out_bump){
- rle->out_bits ++;
- rle->out_bump += 1 << (rle->out_bits - 1);
- }
- if (rle->out_count >= rle->out_clear){
- rle_output(rle->code_clear,rle);
- rle_clear(rle);
- }
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::rle_flush_fromclear(int32_t count,struct_RLE* rle)
-{
- int32_t n;
-
- rle->out_clear = rle->max_ocodes;
- rle->rl_table_pixel = rle->rl_pixel;
- n = 1;
- while (count > 0){
- if (n == 1){
- rle->rl_table_max = 1;
- rle_output_plain(rle->rl_pixel,rle);
- count --;
- } else if (count >= n){
- rle->rl_table_max = n;
- rle_output_plain(rle->rl_basecode+n-2,rle);
- count -= n;
- } else if (count == 1){
- rle->rl_table_max ++;
- rle_output_plain(rle->rl_pixel,rle);
- count = 0;
- } else {
- rle->rl_table_max ++;
- rle_output_plain(rle->rl_basecode+count-2,rle);
- count = 0;
- }
- if (rle->out_count == 0) n = 1; else n ++;
- }
- rle_reset_out_clear(rle);
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::rle_reset_out_clear(struct_RLE* rle)
-{
- rle->out_clear = rle->out_clear_init;
- if (rle->out_count >= rle->out_clear){
- rle_output(rle->code_clear,rle);
- rle_clear(rle);
- }
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::rle_flush_withtable(int32_t count, struct_RLE* rle)
-{
- int32_t repmax;
- int32_t repleft;
- int32_t leftover;
-
- repmax = count / rle->rl_table_max;
- leftover = count % rle->rl_table_max;
- repleft = (leftover ? 1 : 0);
- if (rle->out_count+repmax+repleft > rle->max_ocodes){
- repmax = rle->max_ocodes - rle->out_count;
- leftover = count - (repmax * rle->rl_table_max);
- repleft = 1 + rle_compute_triangle_count(leftover,rle->max_ocodes);
- }
- if (1+rle_compute_triangle_count(count,rle->max_ocodes) < (uint32_t)(repmax+repleft)){
- rle_output(rle->code_clear,rle);
- rle_clear(rle);
- rle_flush_fromclear(count,rle);
- return;
- }
- rle->out_clear = rle->max_ocodes;
- for (;repmax>0;repmax--) rle_output_plain(rle->rl_basecode+rle->rl_table_max-2,rle);
- if (leftover){
- if (rle->just_cleared){
- rle_flush_fromclear(leftover,rle);
- } else if (leftover == 1){
- rle_output_plain(rle->rl_pixel,rle);
- } else {
- rle_output_plain(rle->rl_basecode+leftover-2,rle);
- }
- }
- rle_reset_out_clear(rle);
-}
-////////////////////////////////////////////////////////////////////////////////
-uint32_t CxImageGIF::rle_compute_triangle_count(uint32_t count, uint32_t nrepcodes)
-{
- uint32_t perrep;
- uint32_t cost;
-
- cost = 0;
- perrep = (nrepcodes * (nrepcodes+1)) / 2;
- while (count >= perrep){
- cost += nrepcodes;
- count -= perrep;
- }
- if (count > 0){
- uint32_t n;
- n = rle_isqrt(count);
- while ((n*(n+1)) >= 2*count) n --;
- while ((n*(n+1)) < 2*count) n ++;
- cost += n;
- }
- return(cost);
-}
-////////////////////////////////////////////////////////////////////////////////
-uint32_t CxImageGIF::rle_isqrt(uint32_t x)
-{
- uint32_t r;
- uint32_t v;
-
- if (x < 2) return(x);
- for (v=x,r=1;v;v>>=2,r<<=1) ;
- for( ;; )
- {
- v = ((x / r) + r) / 2;
- if ((v == r) || (v == r+1)) return(r);
- r = v;
- }
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::rle_flush_clearorrep(int32_t count, struct_RLE* rle)
-{
- int32_t withclr;
- withclr = 1 + rle_compute_triangle_count(count,rle->max_ocodes);
- if (withclr < count) {
- rle_output(rle->code_clear,rle);
- rle_clear(rle);
- rle_flush_fromclear(count,rle);
- } else {
- for (;count>0;count--) rle_output_plain(rle->rl_pixel,rle);
- }
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::rle_write_block(struct_RLE* rle)
-{
- g_outfile->PutC((uint8_t)rle->oblen);
- g_outfile->Write(rle->oblock,1,rle->oblen);
- rle->oblen = 0;
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::rle_block_out(uint8_t c, struct_RLE* rle)
-{
- rle->oblock[rle->oblen++] = c;
- if (rle->oblen >= 255) rle_write_block(rle);
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::rle_block_flush(struct_RLE* rle)
-{
- if (rle->oblen > 0) rle_write_block(rle);
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::rle_output(int32_t val, struct_RLE* rle)
-{
- rle->obuf |= val << rle->obits;
- rle->obits += rle->out_bits;
- while (rle->obits >= 8){
- rle_block_out((uint8_t)(rle->obuf&0xff),rle);
- rle->obuf >>= 8;
- rle->obits -= 8;
- }
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::rle_output_flush(struct_RLE* rle)
-{
- if (rle->obits > 0) rle_block_out((uint8_t)(rle->obuf),rle);
- rle_block_flush(rle);
-}
-////////////////////////////////////////////////////////////////////////////////
-void CxImageGIF::compressRLE( int32_t init_bits, CxFile* outfile)
-{
- g_init_bits = init_bits;
- g_outfile = outfile;
-
- struct_RLE rle;
- rle.code_clear = 1 << (init_bits - 1);
- rle.code_eof = rle.code_clear + 1;
- rle.rl_basecode = rle.code_eof + 1;
- rle.out_bump_init = (1 << (init_bits - 1)) - 1;
- rle.out_clear_init = (init_bits <= 3) ? 9 : (rle.out_bump_init-1);
- rle.out_bits_init = init_bits;
- rle.max_ocodes = (1 << MAXBITSCODES) - ((1 << (rle.out_bits_init - 1)) + 3);
- rle.rl_count = 0;
- rle_clear(&rle);
- rle.obuf = 0;
- rle.obits = 0;
- rle.oblen = 0;
-
- rle_output(rle.code_clear,&rle);
-
- int32_t c;
- for( ;; )
- {
- c = GifNextPixel();
- if ((rle.rl_count > 0) && (c != rle.rl_pixel)) rle_flush(&rle);
- if (c == EOF) break;
- if (rle.rl_pixel == c){
- rle.rl_count++;
- } else {
- rle.rl_pixel = c;
- rle.rl_count = 1;
- }
- }
- rle_output(rle.code_eof,&rle);
- rle_output_flush(&rle);
-}
-////////////////////////////////////////////////////////////////////////////////
-#endif // CXIMAGE_SUPPORT_GIF
|