diff options
Diffstat (limited to 'ui')
| -rw-r--r-- | ui/gfx/codec/jpeg_codec.cc | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/ui/gfx/codec/jpeg_codec.cc b/ui/gfx/codec/jpeg_codec.cc index 0558c93..757686b 100644 --- a/ui/gfx/codec/jpeg_codec.cc +++ b/ui/gfx/codec/jpeg_codec.cc @@ -216,7 +216,31 @@ bool JPEGCodec::Encode(const unsigned char* input, ColorFormat format, cinfo.image_width = w; cinfo.image_height = h; cinfo.input_components = 3; +#ifdef JCS_EXTENSIONS + // Choose an input colorspace and return if it is an unsupported one. Since + // libjpeg-turbo supports all input formats used by Chromium (i.e. RGB, RGBA, + // and BGRA), we just map the input parameters to a colorspace used by + // libjpeg-turbo. + if (format == FORMAT_RGB) { + cinfo.input_components = 3; + cinfo.in_color_space = JCS_RGB; + } else if (format == FORMAT_RGBA || + format == FORMAT_SkBitmap && SK_R32_SHIFT == 0) { + cinfo.input_components = 4; + cinfo.in_color_space = JCS_EXT_RGBX; + } else if (format == FORMAT_BGRA || + format == FORMAT_SkBitmap && SK_B32_SHIFT == 0) { + cinfo.input_components = 4; + cinfo.in_color_space = JCS_EXT_BGRX; + } else { + // We can exit this function without calling jpeg_destroy_compress() because + // CompressDestroyer automaticaly calls it. + NOTREACHED() << "Invalid pixel format"; + return false; + } +#else cinfo.in_color_space = JCS_RGB; +#endif cinfo.data_precision = 8; jpeg_set_defaults(&cinfo); @@ -235,6 +259,15 @@ bool JPEGCodec::Encode(const unsigned char* input, ColorFormat format, jpeg_start_compress(&cinfo, 1); // feed it the rows, doing necessary conversions for the color format +#ifdef JCS_EXTENSIONS + // This function already returns when the input format is not supported by + // libjpeg-turbo and needs conversion. Therefore, we just encode lines without + // conversions. + while (cinfo.next_scanline < cinfo.image_height) { + const unsigned char* row = &input[cinfo.next_scanline * row_byte_width]; + jpeg_write_scanlines(&cinfo, const_cast<unsigned char**>(&row), 1); + } +#else if (format == FORMAT_RGB) { // no conversion necessary while (cinfo.next_scanline < cinfo.image_height) { @@ -264,6 +297,7 @@ bool JPEGCodec::Encode(const unsigned char* input, ColorFormat format, } delete[] row; } +#endif jpeg_finish_compress(&cinfo); return true; @@ -446,7 +480,31 @@ bool JPEGCodec::Decode(const unsigned char* input, size_t input_size, case JCS_GRAYSCALE: case JCS_RGB: case JCS_YCbCr: +#ifdef JCS_EXTENSIONS + // Choose an output colorspace and return if it is an unsupported one. + // Same as JPEGCodec::Encode(), libjpeg-turbo supports all input formats + // used by Chromium (i.e. RGB, RGBA, and BGRA) and we just map the input + // parameters to a colorspace. + if (format == FORMAT_RGB) { + cinfo.out_color_space = JCS_RGB; + cinfo.output_components = 3; + } else if (format == FORMAT_RGBA || + format == FORMAT_SkBitmap && SK_R32_SHIFT == 0) { + cinfo.out_color_space = JCS_EXT_RGBX; + cinfo.output_components = 4; + } else if (format == FORMAT_BGRA || + format == FORMAT_SkBitmap && SK_B32_SHIFT == 0) { + cinfo.out_color_space = JCS_EXT_BGRX; + cinfo.output_components = 4; + } else { + // We can exit this function without calling jpeg_destroy_decompress() + // because DecompressDestroyer automaticaly calls it. + NOTREACHED() << "Invalid pixel format"; + return false; + } +#else cinfo.out_color_space = JCS_RGB; +#endif break; case JCS_CMYK: case JCS_YCCK: @@ -456,7 +514,9 @@ bool JPEGCodec::Decode(const unsigned char* input, size_t input_size, // care about these anyway. return false; } +#ifndef JCS_EXTENSIONS cinfo.output_components = 3; +#endif jpeg_calc_output_dimensions(&cinfo); *w = cinfo.output_width; @@ -468,6 +528,18 @@ bool JPEGCodec::Decode(const unsigned char* input, size_t input_size, // how to align row lengths as we do for the compressor. int row_read_stride = cinfo.output_width * cinfo.output_components; +#ifdef JCS_EXTENSIONS + // Create memory for a decoded image and write decoded lines to the memory + // without conversions same as JPEGCodec::Encode(). + int row_write_stride = row_read_stride; + output->resize(row_write_stride * cinfo.output_height); + + for (int row = 0; row < static_cast<int>(cinfo.output_height); row++) { + unsigned char* rowptr = &(*output)[row * row_write_stride]; + if (!jpeg_read_scanlines(&cinfo, &rowptr, 1)) + return false; + } +#else if (format == FORMAT_RGB) { // easy case, row needs no conversion int row_write_stride = row_read_stride; @@ -508,6 +580,7 @@ bool JPEGCodec::Decode(const unsigned char* input, size_t input_size, converter(rowptr, *w, &(*output)[row * row_write_stride]); } } +#endif jpeg_finish_decompress(&cinfo); jpeg_destroy_decompress(&cinfo); |