Function saveAsPNG

mapimageio.c:364–537

}

int saveAsPNG(mapObj *map,rasterBufferObj *rb, streamInfo *info, outputFormatObj *format) {
    int force_pc256 = MS_FALSE;
    int force_palette = MS_FALSE;
   
    int ret = MS_FAILURE;

    const char *force_string,*zlib_compression;
    int compression = -1;

    zlib_compression = msGetOutputFormatOption( format, "COMPRESSION", NULL);
    if(zlib_compression && *zlib_compression) {
      char *endptr;
      compression = strtol(zlib_compression,&endptr,10);
      if(*endptr || compression<-1 || compression>9) {
         msSetError(MS_MISCERR,"failed to parse FORMATOPTION \"COMPRESSION=%s\", expecting integer from 0 to 9.","saveAsPNG()",zlib_compression);
         return MS_FAILURE;
      }
    }

   
    force_string = msGetOutputFormatOption( format, "QUANTIZE_FORCE", NULL );
    if( force_string && (strcasecmp(force_string,"on") == 0  || strcasecmp(force_string,"yes") == 0 || strcasecmp(force_string,"true") == 0) )
        force_pc256 = MS_TRUE;

    force_string = msGetOutputFormatOption( format, "PALETTE_FORCE", NULL );
    if( force_string && (strcasecmp(force_string,"on") == 0  || strcasecmp(force_string,"yes") == 0 || strcasecmp(force_string,"true") == 0) )
        force_palette = MS_TRUE;
       
    if(force_pc256 || force_palette) {
        rasterBufferObj qrb;
        rgbaPixel palette[256], paletteGiven[256];
        unsigned int numPaletteGivenEntries;
        memset(&qrb,0,sizeof(rasterBufferObj));
        qrb.type = MS_BUFFER_BYTE_PALETTE;
        qrb.width = rb->width;
        qrb.height = rb->height;
        qrb.data.palette.pixels = (unsigned char*)malloc(qrb.width*qrb.height*sizeof(unsigned char));
        qrb.data.palette.scaling_maxval = 255;
        if(force_pc256) {
            qrb.data.palette.palette = palette;
            qrb.data.palette.num_entries = atoi(msGetOutputFormatOption( format, "QUANTIZE_COLORS", "256"));
            ret = msQuantizeRasterBuffer(rb,&(qrb.data.palette.num_entries),qrb.data.palette.palette,
                  NULL, 0,
                  &qrb.data.palette.scaling_maxval);
        } else {
            int colorsWanted = atoi(msGetOutputFormatOption( format, "QUANTIZE_COLORS", "0"));
            const char *palettePath = msGetOutputFormatOption( format, "PALETTE", "palette.txt");
            char szPath[MS_MAXPATHLEN];
            if(map) {
               msBuildPath(szPath, map->mappath, palettePath);
               palettePath = szPath;
            }
            if(readPalette(palettePath,paletteGiven,&numPaletteGivenEntries,format->transparent) != MS_SUCCESS) {
                return MS_FAILURE;
            }
         
            if(numPaletteGivenEntries == 256 || colorsWanted == 0) {
                qrb.data.palette.palette = paletteGiven;