* We don't need to change DecodeAlpha, since incremental
decoding is not useful for Alpha (we already decode
progressively along the RGB)
* Similarly, we don't do incremental decoding for level>0 planes:
the metadata don't turn into visible pixel (only the ones in level0), so...
(No visible speed change)
Change-Id: I2fd4b9ba227561a7dbede647686584b752be7baa
- don't call VP8LClear() when there's no error (and let the caller do it)
- only initialize output once if state_ is not READ_DATA
- don't over-set dec->status_ = READ_DATA
- don't re-set dec->status_ if DecodeImageStream() fails
- remove unneeded dec->action_ field
- make ReadImageInfo() check br->eos_
- use ErrorStatusLossless() more consistently
Change-Id: Ica6e4b1c82e3fce8b1ce0274def551a886b73b0b
Handle the corner case when VP8LDecodeImage() method is called with an invalid
header data. The lossless decoding doesn't support incremental mode yet.
Return the error status as BITSTREAM error in case not all pixels are decoded
with the provided bit-stream. Also added asserts in the VP8LDecodeImage() method
to validate the decoder header with appropriate/valid data for huffman trees
(htree_groups_ etc).
Change-Id: Ibac9fcfc4bd0a2c5f624bb9d4a2b9f6459aa19ea
there's still some malloc/free in the external example
This is an encoder API change because of the introduction
of WebPMemoryWriterClear() for symmetry reasons.
The MemoryWriter object should probably go in examples/ instead
of being in the main lib, though.
mux_types.h stil contain some inlined free()/malloc() that are
harder to remove (we need to put them in the libwebputils lib
and make sure link is ok). Left as a TODO for now.
Also: WebPDecodeRGB*() function are still returning a pointer
that needs to be free()'d. We should call WebPSafeFree() on
these, but it means exposing the whole mechanism. TODO(later).
Change-Id: Iad2c9060f7fa6040e3ba489c8b07f4caadfab77b
(instead of per-macroblock)
speed unchanged.
simplified the context-saving for incremental decoding
Change-Id: I301be581bab581ff68de14c4ffe5bc0ec63f34be
New API options: WebPDecoderOptions.flip and 'dwebp -flip ...'
it uses negative stride trick.
Also changed the decoder code to support user-supplied
buffers with negative stride, independently of the
WebPDecoderOptions.flip value.
Change-Id: I4dc0d06f0c87e51a3f3428be4fee2d6b5ad76053
Even at high quality setting, the U/V quantizer step is limited
to 4 which can lead to banding on gradient.
This option allows to selectively apply some randomness to
potentially flattened-out U/V blocks and attenuate the banding.
This option is off by default in 'dwebp', but set to -dither 50
by default in 'vwebp'.
Note: depending on the number of blocks selectively dithered,
we can have up to a 10% slow-down in decoding speed it seems.
Change-Id: Icc2446007f33ddacb60b3a80a9e63f2d5ad162de
method 1 grouping: [parse + reconstruction] // [filtering + output]
method 2 grouping: [parse] // [reconstruction+filtering + output]
Depending on some heuristics (see VP8ThreadMethod()), we
can pick one of the other when -mt flag (or option.use_threads)
is selected.
Conservatively, we always use method #2 for now until the heuristic
is refined (so, timing should be the same the before this patch)
+ replace 'use_threads' by 'mt_method'
+ define MIN_WIDTH_FOR_THREADS constant
+ fix comment alignment
Change-Id: I11a756dea9070d6e21b1a9481d357a1e8aa0663e
Mostly visible for large images.
Reconstruction+filtering is now done in parallel to bitstream-parsing.
Change-Id: I4cc4483d803b255f4d97a2fcd9158b1c291dd900
Needs more memory but allows for future parallelization.
Noticeably faster on ARM, slightly faster on x86
also: remove dec->filter_row_ unnecessary field
Change-Id: I044a808839b4e000c838a477e3e8688820436d9a
happens when decoding is partial (past Partition0), without error and
interrupted by calling WebPIDelete()
WebPIDelete() needs to call VP8ExitCritical() to free in-flight resources
Change-Id: Id4faef1b92f7edd8c17d642c58860e70dd570506
rather than symlink the webm/vpx terms, use the same header as libvpx to
reference in-tree files
based on the discussion in:
https://codereview.chromium.org/12771026/
Change-Id: Ia3067ecddefaa7ee01550136e00f7b3f086d4af4
This applies to images with optional chunks (e.g. images with ALPH
chunk,
ICCP chunk etc). Before this, the incremental decoding used to work like
non-incremental decoding for such files, that is, no rows were decoded
until
all data was available.
The change is in 2 parts:
- During optional chunk parsing, don't wait for the full VP8/VP8L chunk.
- Remap 'alpha_data' pointer whenever a new buffer is allocated/used in
WebPIAppend() and WebPIUpdate().
Change-Id: I6cfd6ca1f334b9c6610fcbf662cd85fa494f2a91
If a NULL pre-allocated buffer is passed, a buffer will be automatically
allocated.
+ add some parameter checks.
reported in http://code.google.com/p/webp/issues/detail?id=139
Change-Id: I9e14ed97db30ee12e46b5e92aac7eeaaeb99bfd5
- precompute filtering strength once for all at the beginning
instead of per-macroblock
- reduce size of VP8MB struct from 8 bytes to 4.
- removed VP8StoreBlock() accordingly
Change-Id: Icf3d329473e21c464770be3d72a04c9ee4c321f2
* each with their own decoder instances.
* Refactor the incremental buffer-update code a lot.
* remove br_offset_ for VP8LDecoder along the way
* make VP8GetHeaders() be used only for VP8, not VP8L bitstream
* remove VP8LInitDecoder()
* rename VP8LBitReaderResize() to VP8LBitReaderSetBuffer()
(cherry picked from commit 5529a2e6d47212a721ca4ab003215f97bd88ebb4)
Change-Id: I58f0b8abe1ef31c8b0e1a6175d2d86b863793ead
import changes from experimental 5529a2e^
and enable build in autoconf and makefile.unix; windows will be treated
separately.
Change-Id: Ie2e177a99db63190b4cd647b3edee3b4e13719e9
A call to Append/Update would index the parts_ array w/-1 as num_parts_
had yet to be set by DecodePartition0. This would cause corruption
within the VP8Decoder member.
Fixes issue #106.
Change-Id: Ib9f2811594ff19e948a66fda862a4e0a384bb9aa
If the first call to WebPIUpdate contained all of partition 0, but not
enough to decode a macroblock the test for max macro block size could
fail (4096 bytes) due to a memory buffer offset not being updated.
This change offsets the buffer in the same manner as Append().
Fixes issue #105.
Change-Id: I90ca3d0dde92eedc076933b8349d2d297f2469e8
alpha information is not to be found at RIFF chunks level, not
in the VP8 bitstream (that was a tmp hack)
Change-Id: Idd1629c696b03c26f6f30650d7216f627f1761df
Extend WebP decode functionality to extract Alpha data (support ALPH
chunk) and decode the Alpha plane using Alpha (utils/alpha) core-lib.
Change-Id: I6f0ee1b189c13caba3c1dd9b681383bfd00aa212
- Move common defines to dec/webpi.h
- Regularize naming and parameters of various "CheckAndSkip" functions.
Also they return VP8StatusCode for clarity.
- Move WebP header/chunk parsing functions to webpi.h
- Fix a bug in static function GetFeatures()
Change-Id: Ibc3da4ba210d860551724dc40741959750d66b89
To be enabled with the flag WEBP_USE_THREAD.
For now it's only available on unix (pthread), when using Makefile.unix
Will be switched on more generally later.
In-loop filtering and output (=rescaling/yuv->rgb conversion)
is done in parallel to bitstream decoding, lagging 1 row behind.
Example:
examples/dwebp bryce.webp -v
Time to decode picture: 0.680s
examples/dwebp bryce.webp -v -mt
Time to decode picture: 0.515s
Change-Id: Ic30a897423137a3bdace9c4e30465ef758fe53f2
