diff options
| author |  Mike Reed <reed@google.com> | 2017-11-30 15:33:04 -0500 |
|---|---|---|
| committer |  Skia Commit-Bot <skia-commit-bot@chromium.org> | 2017-11-30 21:06:38 +0000 |
| commit | d6cb11ee9df514a3a65b313725d3ac3bfd003e7f (patch) | |
| tree | f2381b95ecb3fe1368b7021f16783376b8c6ea51 /src/codec/SkPngPriv.h | |
| parent | 74663e722ea905972e62c59e60cd0cbc97e8435f (diff) | |
encode kAlpha_8 as grayalpha with sigbits for gray==1
Bug: skia:
Change-Id: Ib61e8e0f62af92d8746f5e73469002e7804a8447
Reviewed-on: https://skia-review.googlesource.com/78481
Reviewed-by: Leon Scroggins <scroggo@google.com>
Commit-Queue: Mike Reed <reed@google.com>
Diffstat (limited to 'src/codec/SkPngPriv.h')
| -rw-r--r-- | src/codec/SkPngPriv.h | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/src/codec/SkPngPriv.h b/src/codec/SkPngPriv.h new file mode 100644 index 0000000000..3269309075 --- /dev/null +++ b/src/codec/SkPngPriv.h @@ -0,0 +1,19 @@ +/* + * Copyright 2017 Google Inc. + * + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +#ifndef SkPngPriv_DEFINED +#define SkPngPriv_DEFINED + +#include "SkTypes.h" + +// We store kAlpha_8 images as GrayAlpha in png. Our private signal is significant bits for gray. +// If that is set to 1, we assume the gray channel can be ignored, and we output just alpha. +// We tried 0 at first, but png doesn't like a 0 sigbit for a channel it expects, hence we chose 1. + +static constexpr int kGraySigBit_GrayAlphaIsJustAlpha = 1; + +#endif |