diff options
Diffstat (limited to 'src/im_format_png.cpp')
| -rw-r--r-- | src/im_format_png.cpp | 52 |
1 files changed, 38 insertions, 14 deletions
diff --git a/src/im_format_png.cpp b/src/im_format_png.cpp index 314f07f..5c508e1 100644 --- a/src/im_format_png.cpp +++ b/src/im_format_png.cpp @@ -3,7 +3,7 @@ * * See Copyright Notice in im_lib.h * See libPNG Copyright Notice in png.h - * $Id: im_format_png.cpp,v 1.2 2008/12/03 15:45:34 scuri Exp $ + * $Id: im_format_png.cpp,v 1.3 2009/08/13 22:34:25 scuri Exp $ */ #include "im_format.h" @@ -277,14 +277,25 @@ void imFileFormatPNG::iReadAttrib(imAttribTable* attrib_table) attrib_table->Set("CalibrationParam", IM_BYTE, total_size+1, param_buf); } - int num_trans; - png_bytep trans; - png_color_16p trans_values; + int num_trans = 0; + png_bytep trans = NULL; + png_color_16p trans_values = NULL; if (png_get_tRNS(png_ptr, info_ptr, &trans, &num_trans, &trans_values)) { if (imColorModeSpace(file_color_mode) == IM_MAP) { - attrib_table->Set("TransparencyIndex", IM_BYTE, num_trans, trans); + int i, min_alpha = 256; + imbyte transp_index = 0; + attrib_table->Set("TransparencyMap", IM_BYTE, num_trans, trans); + for (i=0; i<num_trans; i++) + { + if (trans[i] < min_alpha) + { + min_alpha = trans[i]; + transp_index = (imbyte)i; + } + } + attrib_table->Set("TransparencyIndex", IM_BYTE, 1, &transp_index); } else if (imColorModeSpace(file_color_mode) == IM_RGB) { @@ -292,12 +303,12 @@ void imFileFormatPNG::iReadAttrib(imAttribTable* attrib_table) transp_color[0] = (imbyte)(trans_values->red >> 8); transp_color[1] = (imbyte)(trans_values->green >> 8); transp_color[2] = (imbyte)(trans_values->blue >> 8); - attrib_table->Set("TransparentColor", IM_BYTE, 3, transp_color); + attrib_table->Set("TransparencyColor", IM_BYTE, 3, transp_color); } - else + else if (imColorModeSpace(file_color_mode) == IM_GRAY) { - imbyte bvalue = (imbyte)(trans_values->gray >> 8); - attrib_table->Set("TransparencyIndex", IM_BYTE, 1, &bvalue); + imbyte transp_index = (imbyte)(trans_values->gray >> 8); + attrib_table->Set("TransparencyIndex", IM_BYTE, 1, &transp_index); } } @@ -499,24 +510,37 @@ void imFileFormatPNG::iWriteAttrib(imAttribTable* attrib_table) png_set_pCAL(png_ptr, info_ptr, name, limits[0], limits[1], *equation, nparams, units, pparams); } - int transp_count; - attrib_data = attrib_table->Get("TransparencyIndex", NULL, &transp_count); + attrib_data = attrib_table->Get("TransparencyIndex", NULL, NULL); if (attrib_data) { - png_color_16 trans_values; if (imColorModeSpace(file_color_mode) == IM_MAP) { - png_set_tRNS(png_ptr, info_ptr, (imbyte*)attrib_data, transp_count, NULL); + int i; + imbyte transp_index = *(imbyte*)attrib_data; + imbyte transp_map[256]; + for (i=0; i<256; i++) + transp_map[i] = 255; + transp_map[transp_index] = 0; + png_set_tRNS(png_ptr, info_ptr, transp_map, 256, NULL); } else if (imColorModeSpace(file_color_mode) == IM_GRAY) { + png_color_16 trans_values; imbyte *transp_color = (imbyte*)attrib_data; trans_values.gray = (png_uint_16)(transp_color[0] << 8); png_set_tRNS(png_ptr, info_ptr, NULL, 1, &trans_values); } } - attrib_data = attrib_table->Get("TransparentColor"); + int transp_count; + attrib_data = attrib_table->Get("TransparencyMap", NULL, &transp_count); + if (attrib_data) + { + if (imColorModeSpace(file_color_mode) == IM_MAP) + png_set_tRNS(png_ptr, info_ptr, (imbyte*)attrib_data, transp_count, NULL); + } + + attrib_data = attrib_table->Get("TransparencyColor"); if (attrib_data) { if (imColorModeSpace(file_color_mode) == IM_RGB) |