Although it degrades quality, this option is useful to avoid the 512k
limit for partition #0.
If not enough to reach the lower bound of 4bits per macroblock header,
one should also limit the number of segments used (down to -segments 1)
See the man file for extra details.
Change-Id: Ia59ffac13176c85b809ddd6340d37b54ee9487ea
was missing from the RD-computation of intra-4x4 score.
Doesn't change anything significantly, it's just More Correct.
Change-Id: I25c5b53a810d97e6fb7f98c549fd23bbe55e1bf4
with assertions enabled the code would abort in
WebPWorkerChangeState with:
Assertion `worker->status_ >= OK'
without them the code would hang in the _cond_wait.
this change makes WebPWorkerChangeState a no-op in this case.
Change-Id: Iea855568bbdef2865ae61ab54473b3a7c230e91a
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
Add WEBP_EXTERN(type) macro which should make Windows DLL builds simpler
by allowing the signature to be changed.
Change-Id: I0cfa45dff779985680b1a38ddff30973a0d26639
RGB565 and ARGB4444 are only supported through the advanced decoding API.
ARGB being somewhat generic, there's an easy WebPDecodeARGB()
new function for convenience.
Patch by Vikas Arora (vikaas dot arora at gmail dot com)
Change-Id: Ic7b6f72bd70aca458d14e7fdd23679212430ebca
~5-10% faster.
Heavy 8bit arithmetic trickery!
Patch by Somnath Banerjee (somnath at google dot com)
Change-Id: I9fd2c511d9f631e9cf4b008c46127b49fb527b47
You can now use WebPDecBuffer, WebPBitstreamFeatures and WebPDecoderOptions
to have better control over the decoding process (and the speed/quality tradeoff).
WebPDecoderOptions allow to:
- turn fancy upsampler on/off
- turn in-loop filter on/off
- perform on-the-fly cropping
- perform on the-fly rescale
(and more to come. Not all features are implemented yet).
On-the-fly cropping and scaling allow to save quite some memory
(as the decoding operation will now scale with the output's size, not
the input's one). It saves some CPU too (since for instance,
in-loop filtering is partially turned off where it doesn't matter,
and some YUV->RGB conversion operations are ommitted too).
The scaler uses summed area, so is mainly meant to be used for
downscaling (like: for generating thumbnails or previews).
Incremental decoding works with these new options.
More doc to come soon.
dwebp is now using the new decoding interface, with the new flags:
-nofancy
-nofilter
-crop top left width height
-scale width height
Change-Id: I08baf2fa291941686f4ef70a9cc2e4137874e85e
This is a temporary workaround for issue #80.
Currently dec/dsp_sse2 is not included in Makefile.vc. Simply adding it
will cause a build error, however, as cl does not support aligning
function parameters producing, e.g.,
src\dec\dsp_sse2.c(228) : error C2719: 'q1': formal parameter with
__declspec(align('16')) won't be aligned
Change-Id: Id29e6802dd29110e59c4f6d13ffa5d4793c750a0
There was 1 unneeded sample line allocated for the filter cache in of simple filtering.
+ Add an explaining comment.
Change-Id: I775a596c8b8643e773e0eade8aa341dc23fb290f
Only builds with --enable-experimental require zlib currently.
A base install of mingw will not include the development headers and
library. libwebp itself will now build in such environments.
Additionally, remove -lz from **/Makefile.am, -lz will be added to LIBS
by AC_CHECK_LIB when necessary.
Change-Id: Iae8319cdf00162ecb7ed44661c02f40beb34f155
Use _MSC_VER as the intrinsics compile without /arch:SSE2 on x86.
Also avoids applying the same flag to all files which defeated the
purpose of the runtime cpu-detection.
Thanks to Frank B. for the suggestion!
Change-Id: Iae9933a3cee704e663d9bbd53d0fa68e8c025425
picture->error_code can be looked up for finer error diagnose.
Added readable error messages to cwebp too.
Should close bug #75 (http://code.google.com/p/webp/issues/detail?id=75)
Change-Id: I8889d06642d90702f698cd5c27441a058ddb3636
sometimes, gcc insert sse2 storeu instructions (like in VP8InitFilter())
with aligment requirements.
Bug was visible 'sometimes' in non-debug mode, when trying to use -af.
Change-Id: If3ec282bbbb9f9d0d33ca4b2c4bed46cd26fe495
we were reading past the end of the dqs[] array.
reported by Mathias Schindler (on cygwin only)
http://code.google.com/p/webp/issues/detail?id=71
Change-Id: Ib38c4c139e3cac3e8915626d63e16b403d6bbd63
+ add a simple rescaling function: WebPPictureRescale() for encoding
+ clean-up the memory managment around the alpha plane
+ fix some includes path by using "../webp/xxx.h" instead of "webp/xxx.h"
New flags for 'cwebp':
-resize <width> <height>
-444 (no effect)
-422 (no effect)
-400
Change-Id: I25a95f901493f939c2dd789e658493b83bd1abfa
This is a (minor) bitstream change: if the 'color_space' bit is set to '1'
(which is normally an undefined/invalid behaviour), we add extra data at the
end of partition #0 (so-called 'extensions')
Namely, we add the size of the extension data as 3 bytes (little-endian),
followed by a set of bits telling which extensions we're incorporating.
The data then _preceeds_ this trailing tags.
This is all experimental, and you'll need to have
'#define WEBP_EXPERIMENTAL_FEATURES' in webp/types.h to enable this code
(at your own risk! :))
Still, this hack produces almost-valid WebP file for decoders that don't
check this color_space bit. In particular, previous 'dwebp' (and for instance
Chrome) will recognize this files and decode them, but without the alpha
of course. Other decoder will just see random extra stuff at the end of
partition #0.
To experiment with the alpha-channel, you need to compile on Unix platform
and use PNGs for input/output.
If 'alpha.png' is a source with alpha channel, then you can try (on Unix):
cwebp alpha.png -o alpha.webp
dwebp alpha.webp -o test.png
cwebp now has a '-noalpha' flag to ignore any alpha information from the
source, if present.
More hacking and experimenting welcome!
Change-Id: I3c7b1fd8411c9e7a9f77690e898479ad85c52f3e
For now, SSE2 functions are compiled a-minima: only on platforms
where __SSE2__ is defined. Let's later add some autoconf-based
config to enable/disable at will.
One can disable SSE2 at run-time by hooking-up VP8GetInfo.
There is a new option "-noasm" in cwebp for that.
Output should be binary the same between C and SSE2 version. If not,
that's a bug!
patch by Christian Duvivier (cduvivier at google dot com)
Change-Id: Iae006c3cdcb7e8280e846cedb94d239dab1e42ae
to return the sum directly.
output is bitwise the same, speed up 1-2%. This is preparatory to a
more efficient SSE2 implementation.
Change-Id: I0bcdf05808c93420fbe9dcb75e5e7e55a4ae5b89
Makes things lighter at the expense of requiring the user
to be up-to-date for autotools.
patch by Jan Engelhardt (jengelh at medozas dot de)
Change-Id: Icfcab2d899828a213d9fade0dab350dacd0c070a
going down to strict -ansi c89 is quite overkill (no 'inline',
and /* */-style comments).
But with these fixes, the code compiles with the stringent flags:
-Wextra -Wold-style-definition -Wmissing-prototypes
-Wmissing-declarations and -Wdeclaration-after-statement
Change-Id: I36222f8f505bcba3d9d1309ad98b5ccb04ec17e3
WebPGetDecoderVersion() and WebPGetEncoderVersion()
will not return 0.1.2 encoded as 0x000102
dwebp and cwebp also have a new "-version" flag
Change-Id: I4fb4b5a8fc4e53681a386ff4b74fffb639fa237a
The object WebPIDecoder is available to store the
decoding state. The flow is typically:
WebPIDecoder* const idec = WebPINew(mode);
while (has_more_data) {
// ... (get additional data)
status = WebPIAppend(idec, new_data, new_data_size);
if (status != VP8_STATUS_SUSPENDED ||
break;
}
// The above call decodes the current available buffer.
// Part of the image can now be refreshed by calling to
// WebPIDecGetRGB()/WebPIDecGetYUV() etc.
}
WebPIDelete(idec);
Doing so, one can try and decode new macroblocks everytime fresh
bytes are available.
There's two operating modes: either appending fresh bytes, or
updating the whole buffer with additional data in the end.
The latter requires less memcpy()'s
main patch by Somnath Banerjee (somnath at google.com)
Change-Id: Ie81cbd0b50f175743af06b1f964de838b9a10a4a
use top_srcdir rather than top_builddir for AM_CPPFLAGS
add EXTRA_DIST to man Makefile. fixes distcheck target.
Change-Id: I308dc1c98f096de1efe188f63d040ef953598e78
non-zero dc-bit was mixed with non-zero ac-bit, preventing
finer optimization during VP8ReconstructBlock.
Depending on sparsity, i see 2-5% gain on average.
Change-Id: I7f34f18d0701c77837de3540b732e5b7d85d7c5d
(this makes initialization easier and will be helpful for incremental
decoding).
Modify ParsePartitions() to accommodate for truncated input.
Change-Id: I62f52078d6b7a2314a11880a20d9eac5b4714bd0
