int SplashDecodePng(Splash * splash, png_rw_ptr read_func, void *io_ptr) { int stride; ImageFormat srcFormat; png_uint_32 i, rowbytes; png_bytepp row_pointers = NULL; png_bytep image_data = NULL; int success = 0; double gamma; png_structp png_ptr = NULL; png_infop info_ptr = NULL; png_uint_32 width, height; int bit_depth, color_type; ImageRect srcRect, dstRect; png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); if (!png_ptr) { goto done; } info_ptr = png_create_info_struct(png_ptr); if (!info_ptr) { goto done; } #ifdef __APPLE__ /* use setjmp/longjmp versions that do not save/restore the signal mask */ if (_setjmp(png_set_longjmp_fn(png_ptr, _longjmp, sizeof(jmp_buf)))) { #else if (setjmp(png_jmpbuf(png_ptr))) { #endif goto done; } png_set_read_fn(png_ptr, io_ptr, read_func); png_set_sig_bytes(png_ptr, SIG_BYTES); /* we already read the 8 signature bytes */ png_read_info(png_ptr, info_ptr); /* read all PNG info up to image data */ png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, NULL, NULL, NULL); /* expand palette images to RGB, low-bit-depth grayscale images to 8 bits, * transparency chunks to full alpha channel; strip 16-bit-per-sample * images to 8 bits per sample; and convert grayscale to RGB[A] * this may be sub-optimal but this simplifies implementation */ png_set_expand(png_ptr); png_set_tRNS_to_alpha(png_ptr); png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER); png_set_strip_16(png_ptr); png_set_gray_to_rgb(png_ptr); if (png_get_gAMA(png_ptr, info_ptr, &gamma)) png_set_gamma(png_ptr, 2.2, gamma); png_set_interlace_handling(png_ptr); png_read_update_info(png_ptr, info_ptr); rowbytes = png_get_rowbytes(png_ptr, info_ptr); if (!SAFE_TO_ALLOC(rowbytes, height)) { goto done; } if ((image_data = (unsigned char *) malloc(rowbytes * height)) == NULL) { goto done; } if (!SAFE_TO_ALLOC(height, sizeof(png_bytep))) { goto done; } if ((row_pointers = (png_bytepp) malloc(height * sizeof(png_bytep))) == NULL) { goto done; } for (i = 0; i < height; ++i) row_pointers[i] = image_data + i * rowbytes; png_read_image(png_ptr, row_pointers); SplashCleanup(splash); splash->width = width; splash->height = height; if (!SAFE_TO_ALLOC(splash->width, splash->imageFormat.depthBytes)) { goto done; } stride = splash->width * splash->imageFormat.depthBytes; if (!SAFE_TO_ALLOC(splash->height, stride)) { goto done; } splash->frameCount = 1; splash->frames = (SplashImage *) malloc(sizeof(SplashImage) * splash->frameCount); if (splash->frames == NULL) { goto done; } splash->loopCount = 1; splash->frames[0].bitmapBits = malloc(stride * splash->height); if (splash->frames[0].bitmapBits == NULL) { free(splash->frames); goto done; } splash->frames[0].delay = 0; /* FIXME: sort out the real format */ initFormat(&srcFormat, 0xFF000000, 0x00FF0000, 0x0000FF00, 0x000000FF); srcFormat.byteOrder = BYTE_ORDER_MSBFIRST; initRect(&srcRect, 0, 0, width, height, 1, rowbytes, image_data, &srcFormat); initRect(&dstRect, 0, 0, width, height, 1, stride, splash->frames[0].bitmapBits, &splash->imageFormat); convertRect(&srcRect, &dstRect, CVT_COPY); SplashInitFrameShape(splash, 0); png_read_end(png_ptr, NULL); success = 1; done: free(row_pointers); free(image_data); png_destroy_read_struct(&png_ptr, &info_ptr, NULL); return success; } int SplashDecodePngStream(Splash * splash, SplashStream * stream) { unsigned char sig[SIG_BYTES]; int success = 0; stream->read(stream, sig, SIG_BYTES); if (png_sig_cmp(sig, 0, SIG_BYTES)) { goto done; } success = SplashDecodePng(splash, my_png_read_stream, stream); done: return success; }
int GImageWrite_Png(GImage *gi, FILE *fp, int progressive) { struct _GImage *base = gi->list_len==0?gi->u.image:gi->u.images[0]; png_structp png_ptr; png_infop info_ptr; png_byte **rows; int i; int bit_depth; int color_type; int num_palette; png_bytep trans_alpha = NULL; png_color_16p trans_color = NULL; png_colorp palette = NULL; png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, (void *)NULL, user_error_fn, user_warning_fn); if (!png_ptr) { return(false); } info_ptr = png_create_info_struct(png_ptr); if (!info_ptr) { png_destroy_write_struct(&png_ptr, (png_infopp)NULL); return(false); } #if (PNG_LIBPNG_VER < 10500) if (setjmp(png_ptr->jmpbuf)) #else if (setjmp(*png_set_longjmp_fn(png_ptr, longjmp, sizeof (jmp_buf)))) #endif { png_destroy_write_struct(&png_ptr, (png_infopp)NULL); return(false); } png_init_io(png_ptr, fp); bit_depth = 8; num_palette = base->clut==NULL?2:base->clut->clut_len; if ( base->image_type==it_index || base->image_type==it_bitmap ) { color_type = PNG_COLOR_TYPE_PALETTE; if ( num_palette<=2 ) bit_depth=1; else if ( num_palette<=4 ) bit_depth=2; else if ( num_palette<=16 ) bit_depth=4; } else { color_type = PNG_COLOR_TYPE_RGB; if ( base->image_type == it_rgba ) color_type = PNG_COLOR_TYPE_RGB_ALPHA; } png_set_IHDR(png_ptr, info_ptr, base->width, base->height, bit_depth, color_type, progressive, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT); if ( base->image_type==it_index || base->image_type==it_bitmap ) { palette = (png_color *) galloc(num_palette*sizeof(png_color)); if ( base->clut==NULL ) { palette[0].red = palette[0].green = palette[0].blue = 0; palette[1].red = palette[1].green = palette[1].blue = 0xff; } else { for ( i=0; i<num_palette; ++i ) { long col = base->clut->clut[i]; palette[i].red = COLOR_RED(col); palette[i].green = COLOR_GREEN(col); palette[i].blue = COLOR_BLUE(col); } } png_set_PLTE(png_ptr, info_ptr, palette, num_palette); if ( num_palette<=16 ) png_set_packing(png_ptr); if ( base->trans!=-1 ) { trans_alpha = (png_bytep) galloc(1); trans_alpha[0] = base->trans; } } else { if ( base->trans!=-1 ) { trans_color = (png_color_16p) galloc(sizeof(png_color_16)); trans_color->red = COLOR_RED(base->trans); trans_color->green = COLOR_GREEN(base->trans); trans_color->blue = COLOR_BLUE(base->trans); } } if ( base->trans!=-1 ) { png_set_tRNS(png_ptr, info_ptr, trans_alpha, 1, trans_color); } png_write_info(png_ptr, info_ptr); if (color_type == PNG_COLOR_TYPE_RGB) png_set_filler(png_ptr, '\0', PNG_FILLER_BEFORE); rows = (png_byte **) galloc(base->height*sizeof(png_byte *)); for ( i=0; i<base->height; ++i ) rows[i] = (png_byte *) (base->data + i*base->bytes_per_line); png_write_image(png_ptr,rows); png_write_end(png_ptr, info_ptr); if ( trans_alpha!=NULL ) gfree(trans_alpha); if ( trans_color!=NULL ) gfree(trans_color); if ( palette!=NULL ) gfree(palette); png_destroy_write_struct(&png_ptr, &info_ptr); gfree(rows); return( 1 ); }
#if (PNG_LIBPNG_VER < 10500) if (setjmp(png_ptr->jmpbuf)) #else if (setjmp(*png_set_longjmp_fn(png_ptr, longjmp, sizeof (jmp_buf)))) #endif { png_destroy_write_struct(&png_ptr, (png_infopp)NULL); return(false); }