- Update SkCodec's dox to point out that some of the data must be
read twice in order to decode
- Add an accessor that reports how much is needed for reading twice
- Make SkCodec default to use peek()
If an input stream supports peek()ing, peek() instead of reading.
This way the stream need not implement rewind()
- Make SkCodec use read() + rewind() as a backup
So that streams without peek() implemented can still function
properly (assuming they can rewind).
- read everything we may need to determine the format once
In SkCodec::NewFromStream, peek()/read() 14 bytes, which is enough
to read all of the types we support. Pass the buffer to each subtype,
which will have enough info to determine whether it is the right
type. This simplifies the code and results in less reading and
rewinding.
- NOTE: SkWbmpCodec needs the following number of bytes for the header
+ 1 (type)
+ 1 (reserved)
+ 3 (width - bytes needed to support up to 0xFFFF)
+ 3 (height - bytes needed to support up to 0xFFFF)
= 8
- in SkWebpCodec, support using read + rewind as a backup if peek does
not work.
A change in Android will add peek() to JavaInputStreamAdapter.
BUG=skia:3257
Review URL: https://codereview.chromium.org/1472123002
The wbmp version of SkImageDecoder will support decoding an image where
the second byte can be masked away with 0x9F. Prior to this CL, SkCodec
checked that the entire byte was zero. The SkCodec implementation
appears to be more correct (at least according to Wikipedia [1]), but
it also means we could regress if someone was using an image that did
not quite fit the specification.
[1] https://en.wikipedia.org/wiki/Wireless_Application_Protocol_Bitmap_Format
BUG=skia:3257
Review URL: https://codereview.chromium.org/1473673005
This class allows a client of SkCodec to read chunks in the data
stream that are not recognized by libpng. This is used by Android
to specify ninepatch data.
Taken from SkImageDecoder::Peeker. Modify the name of the class
and its method to be more specific to their use. Make
SkImageDecoder::Peeker a subclass of the new class, to help stage
the change in Android.
Add a test to verify that it works.
BUG=skia:4574
BUG=skia:3257
Committed: https://skia.googlesource.com/skia/+/3389e00136188800b98ca69488c0418c374fd78b
Review URL: https://codereview.chromium.org/1040453002
Reason for revert:
Busted Chromium builds:
../../third_party/skia/src/ports/SkImageDecoder_empty.cpp:63:17: error: no type
named 'Peeker' in 'SkImageDecoder'
SkImageDecoder::Peeker* SkImageDecoder::setPeeker(Peeker*) {
~~~~~~~~~~~~~~~~^
../../third_party/skia/src/ports/SkImageDecoder_empty.cpp:63:51: error: unknown
type name 'Peeker'
SkImageDecoder::Peeker* SkImageDecoder::setPeeker(Peeker*) {
Original issue's description:
> Add SkPngChunkReader.
>
> This class allows a client of SkCodec to read chunks in the data
> stream that are not recognized by libpng. This is used by Android
> to specify ninepatch data.
>
> Taken from SkImageDecoder::Peeker. Modify the name of the class
> and its method to be more specific to their use. Make
> SkImageDecoder::Peeker a subclass of the new class, to help stage
> the change in Android.
>
> Add a test to verify that it works.
>
> BUG=skia:4574
> BUG=skia:3257
>
> Committed: https://skia.googlesource.com/skia/+/3389e00136188800b98ca69488c0418c374fd78bTBR=djsollen@google.com,reed@google.com,msarett@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:4574
Review URL: https://codereview.chromium.org/1472863003
This class allows a client of SkCodec to read chunks in the data
stream that are not recognized by libpng. This is used by Android
to specify ninepatch data.
Taken from SkImageDecoder::Peeker. Modify the name of the class
and its method to be more specific to their use. Make
SkImageDecoder::Peeker a subclass of the new class, to help stage
the change in Android.
Add a test to verify that it works.
BUG=skia:4574
BUG=skia:3257
Review URL: https://codereview.chromium.org/1040453002
In SkSampledCodec, allow the native codec to do its scaling first, then
sample on top of that. Since the only codec which can do native scaling
is JPEG, and we know what it can do, hard-code for JPEG. Check to see
if the sampleSize is something JPEG supports, or a multiple of
something it supports. If so, use JPEG directly or combine them.
BUG=skia:4320
Review URL: https://codereview.chromium.org/1417583009
Move convert_CMYK_to_RGBA into two functions in SkSwizzler: one for 565
and one for 8888.
For simplicity, when converting to 8888, we no longer convert in place.
BUG=skia:4476
Review URL: https://codereview.chromium.org/1411083009
We will implement this API using SkCodecs.
SkAndroidCodecs will be used to implement the
BitmapRegionDecoder Java API (and possibly
BitmapFactory).
BUG=skia:
Review URL: https://codereview.chromium.org/1406223002
Now, that we are subsetting, fX0 is not necessarily less than
fSrcWidth (since fSrcWidth is really the subset width).
Ex: We may want a 10 pixel subset starting twenty pixels from the
left edge. In that case, fX0=20 and fSrcWidth=10.
Let's rename the width as fSubsetWidth to avoid confusion
and remove the check.
BUG=skia:
Review URL: https://codereview.chromium.org/1407603003
Rather than implementing some sort of "fill" in every
SkCodec subclass for incomplete images, let's make the
parent class handle this situation.
This includes an API change to SkCodec.h
SkCodec::getScanlines() now returns the number of lines it
read successfully, rather than an SkCodec::Result enum.
getScanlines() most often fails on an incomplete input, in
which case it is useful to know how many lines were
successfully decoded - this provides more information than
kIncomplete vs kSuccess. We do lose information when the
API is used improperly, as we are no longer able to return
kInvalidParameter or kScanlineNotStarted.
Known Issues:
Does not work for incomplete fFrameIsSubset gifs.
Does not work for incomplete icos.
BUG=skia:
Review URL: https://codereview.chromium.org/1332053002
The primary goal of SkScaledCodec is to replace the current
implementation of BitmapRegionDecoder, which depends on modified
versions of libjpeg and libpng, with an implementation that uses
standard versions of the libaries. Since BitmapRegionDecoder only
supports PNG, WEBP and JPEG, limit SkScaledCodec to those classes.
We will focus on those three until we complete this primary goal.
Then we can continue to make SkScaledCodec work for other formats.
Fix some bugs in SkScaledCodec::NewFromStream:
- Handle a NULL input stream properly
- Ensure that the input stream is deleted as expected on bad data
Add tests for these error cases.
BUG=skia:4428
Review URL: https://codereview.chromium.org/1389053002
Benefits:
- This mimics other decoding APIs (including the ones SkCodec relies
on, e.g. a png_struct, which can be used to decode an entire image or
one line at a time).
- It allows a client to ask us to do what we can do efficiently - i.e.
start from encoded data and either decode the whole thing or scanlines.
- It removes the duplicate methods which appeared in both SkCodec and
SkScanlineDecoder (some of which, e.g. in SkJpegScanlineDecoder, just
call fCodec->sameMethod()).
- It simplifies moving more checks into the base class (e.g. the
examples in skbug.com/4284).
BUG=skia:4175
BUG=skia:4284
=====================================================================
SkScanlineDecoder.h/.cpp:
Removed.
SkCodec.h/.cpp:
Add methods, enums, and variables which were previously in
SkScanlineDecoder.
Default fCurrScanline to -1, as a sentinel that start has not been
called.
General changes:
Convert SkScanlineDecoders to SkCodecs.
General changes in SkCodec subclasses:
Merge SkScanlineDecoder implementation into SkCodec. Most (all?) owned
an SkCodec, so they now call this-> instead of fCodec->.
SkBmpCodec.h/.cpp:
Replace the unused rowOrder method with an override for
onGetScanlineOrder.
Make getDstRow const, since it is called by onGetY, which is const.
SkCodec_libpng.h/.cpp:
Make SkPngCodec an abstract class, with two subclasses which handle
scanline decoding separately (they share code for decoding the entire
image). Reimplement onReallyHasAlpha so that it can return the most
recent result (e.g. after a scanline decode which only decoded part
of the image) or a better answer (e.g. if the whole image is known to
be opaque).
Compute fNumberPasses early, so we know which subclass to instantiate.
Make SkPngInterlaceScanlineDecoder use the base class' fCurrScanline
rather than a separate variable.
CodexTest.cpp:
Add tests for the state changes in SkCodec (need to call start before
decoding scanlines; calling getPixels means that start will need to
be called again before decoding more scanlines).
Add a test which decodes in stripes, currently only used for an
interlaced PNG.
TODO: Add tests for onReallyHasAlpha.
Review URL: https://codereview.chromium.org/1365313002
libjpeg-turbo turns on dithering by default. When we
decode to RGBA, it uses Floyd-Steinberg dithering -
consistent with the libjpeg6b gold standard,
When we decode to 565, it uses ordered dithering. Ordered
dithering for 565 is not part of the 6b standard (libjpeg6b
doesn't even support 565) and is causing us a number of
issues:
(1) Ordered dithering + nearest neighbor sampling is
causing checkerboard visual artifacts in some outputs.
(2) The ordered dither function in libjpeg-turbo actually
behaves differently depending on the alignment of the
memory that it decodes into. This means that two image
decodes that should be identical may look different just
because they decode into different memory blocks. This
was causing some diffs on Gold with the scanline_subset
test that were causing me some confusion.
(3) Maybe not the best evidence, but visually I can't tell
a difference with and without dithering (except when
nearest neighbor scaling causes the checkerboard artifact).
(4) Turning off dithering should be a more significant
performance improvement than you might expect.
libjpeg-turbo has SIMD color conversions to 565, but when
dithering is on, it defaults to scalar code.
This CL should make every jpeg decode to 565 on Gold look
slightly different. Yay!
BUG=skia:
Review URL: https://codereview.chromium.org/1349563007
Redesigns SkScanlineDecoder.h to indicate the ordering
in which the scanlines are provided
Refactors SkSwizzler::Fill() to include the zeroInit check
and to actually be correct.
BUG=skia:3257
BUG=skia:4198
Review URL: https://codereview.chromium.org/1287423002
We don't want to test small images on Gold because they are
not interested to look at. Instead, I wrote a unit test to
verify that scaling small images does not cause crashes.
BUG=skia:
Review URL: https://codereview.chromium.org/1287863004
Add more swizzling functions for swizzling to 565. Much of this
code was revived from crrev.com/1055743003 (for BMP). Also added
swizzling functions for WBMP.
Consolidate the static function conversion_possible.
In SkCodec::getPixels, check that the alphatype corresponds to the
colorType. This prevents requesting 565 + non-opaque.
In SkIcoCodec, report that the image is unpremul (instead of
whatever the largest embedded codec thinks), but modify the
requested info to have the alpha type expected/required by the
embedded codec.
Add tests for decoding to 565.
BUG=skia:3257
BUG=skia:3683
Review URL: https://codereview.chromium.org/1277213002
Add a static function to CodexTest, which consolidates decoding,
comparing to an expected SkCodec::Result, and optionally comparing to a
digest.
Test decoding non-opaque to opaque (fails) and premul to unpremul/vice
versa (succeeds).
BUG=skia:3475
Review URL: https://codereview.chromium.org/1277253003
Chromium's test suite contains an RLE image that reports a certain
file size in the header, but then contains additional encoded data.
Our bmp decoder would only decode half of the image, before stopping.
With this fix, we check for additional data before returning
kIncompleteInput.
If this lands, I will upload the test image to the bots.
Also adding an invalid image test to CodexTest.
BUG=skia:
Review URL: https://codereview.chromium.org/1273853004
We are also changing the wbmp to use SkSwizzler. This
will allow us to take advantage of the sampling routines
that are being implemented in SkSwizzler.
The image in this upload came from:
https://commons.wikimedia.org/wiki/File:Android_robot.png
It is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.
BUG=skia:
Review URL: https://codereview.chromium.org/1254483004
Prior to this CL, if a client wanted to decode scanlines, they had to
create an SkCodec in order to get an SkScanlineDecoder. This introduces
complications if input data is not easily shared between the two
objects.
Instead, add methods to SkScanlineDecoder for creating a new one from
input data, and remove the creation functions from SkCodec.
Update DM and tests.
Review URL: https://codereview.chromium.org/1267583002
This allows codecs that support subsets natively (i.e. WEBP) to do so.
Add a field on SkCodec::Options representing the subset.
Add a method on SkCodec to find a valid subset which approximately
matches a desired subset.
Implement subset decodes in SkWebpCodec.
Add a test in DM for decoding subsets.
Notice that we only start on even boundaries. This is due to the
way libwebp's API works. SkWEBPImageDecoder does not take this into
account, which results in visual artifacts.
FIXME: Subsets with scaling are not pixel identical, but close. (This
may be fine, though - they are not perceptually different. We'll just
need to mark another set of images in gold as valid, once
https://skbug.com/4038 is fixed, so we can tests scaled webp without
generating new images on each run.)
Review URL: https://codereview.chromium.org/1240143002
Make getScanlineDecoder return a new object each time, which is
owned by the caller, and independent from any existing scanline
decoders and the SkCodec itself.
Since the SkCodec already contains the entire state machine, and it
is used by the scanline decoders, simply create a new SkCodec which
is now owned by the scanline decoder.
Move code that cleans up after using a scanline decoder into its
destructor
One side effect is that creating the first scanline decoder requires
a duplication of the stream and re-reading the header. (With some
more complexity/changes, we could pass the state machine to the
scanline decoder and make the SkCodec recreate its own state machine
instead.) The typical client of the scanline decoder (region decoder)
uses an SkMemoryStream, so the duplication is cheap, although we
should consider the extra time to reread the header/recreate the state
machine. (If/when we use the scanline decoder for other purposes,
where the stream may not be cheaply duplicated, we should consider
passing the state machine.)
One (intended) result of this change is that a client can create a
new scanline decoder in a new thread, and decode different pieces of
the image simultaneously.
In SkPngCodec::decodePalette, use fBitDepth rather than a parameter.
Review URL: https://codereview.chromium.org/1230033004
SkImageGenerator makes some assumptions that are not necessarily valid
for SkCodec. For example, SkCodec does not assume that it can always be
rewound.
We also have an ongoing question of what an SkCodec should report as
its default settings (i.e. the return from getInfo). It makes sense for
an SkCodec to report that its pixels are unpremultiplied, if that is
the case for the underlying data, but if a client of SkImageGenerator
uses the default settings (as many do), they will receive
unpremultiplied pixels which cannot (currently) be drawn with Skia. We
may ultimately decide to revisit SkCodec reporting an SkImageInfo, but
I have left it unchanged for now.
Import features of SkImageGenerator used by SkCodec into SkCodec.
I have left SkImageGenerator unchanged for now, but it no longer needs
Result or Options. This will require changes to Chromium.
Manually handle the lifetime of fScanlineDecoder, so SkScanlineDecoder.h
can include SkCodec.h (where Result is), and SkCodec.h does not need
to include it (to delete fScanlineDecoder).
In many places, make the following simple changes:
- Now include SkScanlineDecoder.h, which is no longer included by
SkCodec.h
- Use the enums in SkCodec, rather than SkImageGenerator
- Stop including SkImageGenerator.h where no longer needed
Review URL: https://codereview.chromium.org/1220733013
the bottom of the image. In our code before this patch,
this would result in cleanup code in onFinish() never being
called.
We can allow subclasses to take ownership of the
SkScanlineDecoder in order to make sure that it is
finished/deleted before deleting the decode manager.
BUG=skia:
Review URL: https://codereview.chromium.org/1212593003
Based on SkImageDecoder_libwebp.
TODO:
Support YUV? (Longer term - may influence our API for SkImageGenerator)
BUG=skia:3257
Review URL: https://codereview.chromium.org/1044433002
Enables basic decoding for jpegs
Includes rewinding
565, YUV, and Jpeg encoding are not yet implemented
BUG=skia:3257
Review URL: https://codereview.chromium.org/1076923002
We may want to enable swizzles to 565
for images that are encoded in a format
similar to 565, however, we do not want
to take images that decode naturally to
kN32 and then convert them to 565.
***Enable swizzles to kIndex_8. For images
encoded in a color table format, we suggest
that they be decoded to kIndex_8. When we
decode, we only allow conversion to kIndex_8
if it matches the suggested color type (except
wbmp which seems good as is).
***Modify dm to test images that decode to
kIndex_8.
BUG=skia:3257
BUG=skia:3440
Review URL: https://codereview.chromium.org/1055743003
