diff options
author | 2015-11-11 06:41:01 -0800 | |
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committer | 2015-11-11 06:41:02 -0800 | |
commit | b5213e69c599c4ca492bd43fd235d698891ce34c (patch) | |
tree | 705412fff4c6777bb11b22ade9d46858aef2e028 /src/images | |
parent | 8dcdedc4a087ea46ce1e2458d335d60918e56310 (diff) |
Change quality settings on SkImageDecoder_libjpeg
It has been demonstrated that higher quality settings
really do make a difference in the visual quality of
the output image.
https://code.google.com/p/chromium/issues/detail?id=385515
https://code.google.com/p/skia/issues/detail?id=3770
We are planning to replace SkImageDecoder with SkCodec,
and SkCodec will use the higher quality settings. As
a first step, we are using SkCodec as the underlying
implementation for BitmapRegionDecoder. CTS tests require
that BitmapRegionDecoder be a close match to BitmapFactory
(which uses SkImageDecoder), so we must also update the
quality of SkImageDecoder to maintain CTS compatibility.
BUG=skia:
Committed: https://skia.googlesource.com/skia/+/69ad6a9d03dd6f14b7c730465319313725a7c903
Review URL: https://codereview.chromium.org/1412803009
Diffstat (limited to 'src/images')
-rw-r--r-- | src/images/SkImageDecoder_libjpeg.cpp | 28 |
1 files changed, 0 insertions, 28 deletions
diff --git a/src/images/SkImageDecoder_libjpeg.cpp b/src/images/SkImageDecoder_libjpeg.cpp index c80cd9b64f..58eff75dc9 100644 --- a/src/images/SkImageDecoder_libjpeg.cpp +++ b/src/images/SkImageDecoder_libjpeg.cpp @@ -223,35 +223,11 @@ static void set_error_mgr(jpeg_decompress_struct* cinfo, skjpeg_error_mgr* error } /** - * Common code for turning off upsampling and smoothing. Turning these - * off helps performance without showing noticable differences in the - * resulting bitmap. - */ -static void turn_off_visual_optimizations(jpeg_decompress_struct* cinfo) { - SkASSERT(cinfo != nullptr); - /* this gives about 30% performance improvement. In theory it may - reduce the visual quality, in practice I'm not seeing a difference - */ - cinfo->do_fancy_upsampling = 0; - - /* this gives another few percents */ - cinfo->do_block_smoothing = 0; -} - -/** * Common code for setting the dct method. */ static void set_dct_method(const SkImageDecoder& decoder, jpeg_decompress_struct* cinfo) { SkASSERT(cinfo != nullptr); -#ifdef DCT_IFAST_SUPPORTED - if (decoder.getPreferQualityOverSpeed()) { - cinfo->dct_method = JDCT_ISLOW; - } else { - cinfo->dct_method = JDCT_IFAST; - } -#else cinfo->dct_method = JDCT_ISLOW; -#endif } SkColorType SkJPEGImageDecoder::getBitmapColorType(jpeg_decompress_struct* cinfo) { @@ -420,8 +396,6 @@ SkImageDecoder::Result SkJPEGImageDecoder::onDecode(SkStream* stream, SkBitmap* SkASSERT(1 == cinfo.scale_num); cinfo.scale_denom = sampleSize; - turn_off_visual_optimizations(&cinfo); - const SkColorType colorType = this->getBitmapColorType(&cinfo); const SkAlphaType alphaType = kAlpha_8_SkColorType == colorType ? kPremul_SkAlphaType : kOpaque_SkAlphaType; @@ -747,8 +721,6 @@ bool SkJPEGImageDecoder::onDecodeYUV8Planes(SkStream* stream, SkISize componentS SkASSERT(1 == cinfo.scale_num); cinfo.scale_denom = 1; - turn_off_visual_optimizations(&cinfo); - #ifdef ANDROID_RGB cinfo.dither_mode = JDITHER_NONE; #endif |