We don't need to use the exact forward transform,
since it's only a rough evaluation.
-> Removed some shifts and rounding constants.
Change-Id: I3fdf8b4fe9720473894155e1ad0345f4d1fd9a33
In particular, this removes any unnecessary FRGM/ANMF/ANIM chunks, and
indirectly leads to removal of unnecessary VP8X chunks as well.
This is especially useful for GIF to WebP conversion - it saves 56 bytes
(ANMF: 16+8 bytes, ANIM: 6+8 bytes, VP8X: 10+8 bytes) for non-animated GIFs.
Change-Id: I3b50a96ca585844c421b0fa4cd8593e52c3f95c5
This is a correction to the following change:
a00a3daf5b Use 'frgm' instead of 'tile' in
webpmux parameters
Change-Id: I8fa0bce98efdde38827fd25712017a98a6ea7388
- Allow a duration of 0
- Rename LOOP chunk to ANIM and add the background color field to it.
- Add a disposal method field for each animation frame.
- Modify webpmux.c binary interface to allow the input of background color
and disposal methods. Also make '-loop' and '-bgcolor' arguments optional
with some default values.
Change-Id: I807372a61cdb8a0d3080ae3552caf2848070bf4d
10-15% faster encoding.
Almost same output, binary wise. The main difference is
that we can't compute uv_alpha susceptibility, means there
can be subtle differences with different -sns values.
Change-Id: Id1b1a50929bf125b6372212fee1ed75a3bed975f
- Also, use the term 'fragments' instead of 'tiling' in code
- This makes code consistent with the spec.
Change-Id: Ibeccffc35db23bbedb88cc5e18e29e51621931f8
- Make ANMF and FRGM chunks hierarchical so that they encompass all chunks of
that frame.
- Use this in demuxer: stop parsing a frame if all image data for it isn't
available yet. Thus, we have a frame-level incremental support; that is,
all frames that are fully available can be parsed.
- Note: We still keep incremental support for single images - so that they can
be decoded with incremental decoding.
Change-Id: Id1585b16b06caee1d84009c42a25d2de29fa6135
Use separate fourCCs "XMP " and "EXIF" instead of a common "META"
Also, some refactorization in webpmux.c
Change-Id: Iad3337e5c1b81e785c60670ce28b1f536dd7ee31
Number of pairs selected are limited between 25% of histogram
images (at start) and number of histogram images left at any iteration.
Increase the range of iter_mult.
Removed min_cluster_size as parameter for tuning HistogramCombine.
Change-Id: Ia4068cd7af4d0f63c5af9001aceda8a40b9de740
* commit 'v0.2.1':
Update ChangeLog
update NEWS
bump version to 0.2.1
libwebp: validate chunk size in ParseOptionalChunks
cwebp (windows): fix alpha image import on XP
autoconf/libwebp: enable dll builds for mingw
[cd]webp: always output windows errors
fix double to float conversion warning
cwebp: fix jpg encodes on XP
VP8LAllocateHistogramSet: fix overflow in size calculation
GetHistoBits: fix integer overflow
EncodeImageInternal: fix uninitialized free
fix the -g/O3 discrepancy for 32bit compile
fix the BITS=8 case
Make *InitSSE2() functions be empty on non-SSE2 platform
make *InitSSE2() functions be empty on non-SSE2 platform
make VP8DspInitNEON() public
Conflicts:
src/Makefile.am
src/dsp/dec_neon.c
Change-Id: Iddc5152e4a6892db96c12d7c3f74adbc85fe6178
Contributed by Wayne Chen (datoudatou at gmail dot com)
+ some header cleanup
+ remove the NEON suffix in static functions
Change-Id: I75bf5e9b54cf5e1acc53764c6f081d61690f8e3d
(implements the backward and forward transforms in the encoder)
original patch by Wayne Chen (datoudatou at gmail dot com)
Change-Id: Ic00f3bffcdf7a924f043006728735c810ee47a57
- Changed the dynamic range where more aggressive
(BackwardReferencesTraceBackward) heuristic is run from quality > 10
(instead of quality > 25).
- Limit the backward-ref Window size to 16*width & 256*width for lower
qualities ([0, 25[ & [25, 50[) respectively, instead of 1M window.
- Evaluate the params for HashChainFindCopy outside this function call
and pass it, instead of recomputing them for every call.
Change-Id: If9eedfc14b978e7632d7cf69c96186e2910b0554
the max wasn't checked leading to a rollover case, possibly exploitable.
additionally check the RIFF size early, to avoid similar issues.
pulled from chromium:
http://codereview.chromium.org/11229048/
Change-Id: I4050b13a7e61ec023c0ef50958c45f651cf34c49
the multiplications done for total_size would be done with integers,
possibly overflowing, before being promoted to 64-bit for the addition
Change-Id: I32c3a6400fc2ef120c38e01a8693f4cb1727234d
huff_image_size was a size_t (=32 bits with 32-bit builds) which could
rollover causing an incorrectly sized allocation and a crash in lossless
encoding.
fixes issue #128
Change-Id: I0f20cee98c29b2b40b02607930b6b7a7ca56996d
in debug mode, some float operations see their intermediate
values stored in memory rather than staying in the FPU (which
is 80bit precision).
Several fixes are possible (breaking long calculations into
atomic steps for instance), but simpler of all is just about
turning the cost[] array into float* instead of double*.
The code is a tad faster, and i didn't see any major output
size difference.
Change-Id: I053e6d340850f02761687e072b0782c6734d4bf8
this will avoid the "dec_neon.o has no symbol" warning
no change in binary size observed on linux.
Change-Id: Ifd83dfc6a0c61905481599b06cb5e711f55efa7d
the max wasn't checked leading to a rollover case, possibly exploitable.
additionally check the RIFF size early, to avoid similar issues.
pulled from chromium:
http://codereview.chromium.org/11229048/
Change-Id: Ifebc712bf3d3de0129b76ca4c57c68e062abc429
This is mostly for experimentation!
Need to define USE_YUVj flag in the code for that.
suggested by benwreder at hotmail dot com
Change-Id: If0b8e2c1863efc08ce097de6de20f4c7efc3f7e8
LSIM stands for "local similarity": before matching
a compressed pixel to the source, we search around in the source
and minimise the squared error. So, this is close to PSNR calculation,
but mitigates some of its limitations (pure translation and noise for instance).
There's a new -print_lsim option to cwebp too.
Change-Id: Ia38561034c7a90e71d2ea0f55bb1de527eda245b
Make the heuristic for combining Histograms a function of compression
quality. This change will speed-up compression time for compression
quality less than 75. The compression time/density remains unchanged
for compression quality 75 and higher.
Change-Id: I94513d51078340fbc0737d459fab2cebdd2d6082
