Only implemented for PNG.
Add a getter and setter, and sets the default to false in the
constructor. Also copies the setting in copyFieldsToOther.
Fix an indpendent bug where fDitherImage was not being copied in
copyFieldsToOther.
In SkScaledBitmapSampler::begin, consolidate the settings passed in
by passing a const reference to the decoder. The decoder can be
referenced for its settings of dither, unpremultiplied, and now
skipping writing zeroes. Update callers to use the new API. In png
decoder, rather than passing around a pointer to an initial
read of getDitherImage, and potentially changing it, look at the
field on the decoder itself, and modify it directly. This is a
change in behavior - now if that same decoder is used to decode
a different image, the dither setting has changed. I think this is
okay because A) the typical use case is to use a new decoder for
each decode, B) we do not make any promises that a decode does not
change the decoder and C) it makes the code in SkScaledBitmapSampler
much cleaner.
In SkScaledBitmapScampler, add new row procs for skipping zeroes. Now
that choosing the row proc has five dimensions (src config, dst config,
dither, skip writing zeroes, unpremultiplied), use a new method: each
src/dst combination has a function for choosing the right proc depending
on the decoder.
SkScaledBitmapScampler::RowProc is now public for convenience.
Remove Sample_Gray_D8888_Unpremul, which is effectively no different
from Sample_Gray_D8888.
In cases where unpremultiplied was trivial, such as 565 and when
sampling from gray, decoding may now succeed.
Add a benchmark (currently disabled) for comparing the speed of skipping
writing zeroes versus not skipping. For this particular image, which is
mostly transparent pixels, normal decoding took about 3.6 milliseconds,
while skipping zeroes in the decode took only about 2.5 milliseconds
(this is on a Nexus 4). Presumably it would be slower on an image
with a small amount of transparency, but there will be no slowdown
for an image which reports that it has no transparency.
In SkImageRef_ashmem, always skip writing zeroes, since ashmem
memory is guaranteed to be initialized to 0.
Add a flag to skip writing zeroes in skimage.
Add a regression test for choosing the rowproc to ensure I did not
change any behavior accidentally.
BUG=skia:1661
R=reed@google.com
Review URL: https://codereview.chromium.org/24269006
git-svn-id: http://skia.googlecode.com/svn/trunk@11558 2bbb7eff-a529-9590-31e7-b0007b416f81
Only affects factories, static functions that will use the factories,
and subset decoding, which all require rewinding. The decoders
themselves continue to take an SkStream. This is merely documentation
stating which functions will possibly rewind the passed in SkStream.
This is part of the general change to coordinate SkStreams with
Android's streams, which don't necessarily support rewinding in all
cases.
Update callers to use SkStreamRewindable.
BUG=skia:1572
R=bungeman@google.com, reed@google.com
Review URL: https://codereview.chromium.org/23477009
git-svn-id: http://skia.googlecode.com/svn/trunk@11460 2bbb7eff-a529-9590-31e7-b0007b416f81
If the original image is grayscale, allow decoding into A8.
Change the size of PrefConfigTable to allow for 8bit gray, a new source config.
Add a new sampler to SkScaledBitmapSampler to 'convert' to A8.
FIXME: Should there be a dithered option for gray scale?
R=reed@google.com
Review URL: https://codereview.chromium.org/18083026
git-svn-id: http://skia.googlecode.com/svn/trunk@10157 2bbb7eff-a529-9590-31e7-b0007b416f81
SkImageDecoder_CG.cpp:
If a non opaque bitmap was decoded, and the caller wants
unpremultiplied, unpremultiply the colors.
Always use the RGB colorspace, since the other colorspaces
do not match the desired bitmap format.
ImageDecodingTest:
Allow for a difference of 1 in each color component when comparing
the result of premultiplying the unpremultiplied decode with the
premultiplied decode, since I found an image (in WEBP format) where
the unpremultiplied colors did not compare perfectly in my comparison.
R=reed@google.com
Review URL: https://codereview.chromium.org/17084012
git-svn-id: http://skia.googlecode.com/svn/trunk@9628 2bbb7eff-a529-9590-31e7-b0007b416f81
Currently they cannot be used directly by Skia, but
the pixels can be used elsewhere.
SkImageDecoder:
Add functions to require unpremultiplied output
and query the presence of the requirement
SkImageDecoder_libpng:
SkImageDecoder_libwebp:
SkImageDecoder_WIC:
Respect the requirement for unpremultiplied output.
TODO: Fix SkImageDecoder_CG.
SkScaledBitmapSampler:
Add procs to skip premultiplication and a boolean
parameter to use those procs.
ImageDecodingTest:
Test unpremultiplied bitmap decoding.
SampleUnpremul:
Add a sample which allows visually comparing between the
unpremultiplied version (copied into a premultiplied bitmap,
since drawing unpremultiplied is not currently supported)
and a premultiplied version of image files.
gm.h:
Add a getter for the resource path, so Samples can use it.
As of patch set 13, https://codereview.chromium.org/16816016/
and https://codereview.chromium.org/16983004/, which were
approved separately.
R=reed@google.com
Review URL: https://codereview.chromium.org/16410009
git-svn-id: http://skia.googlecode.com/svn/trunk@9612 2bbb7eff-a529-9590-31e7-b0007b416f81
