new options:
dwebp -alpha_dither
vwebp -noalphadither
When the source was marked as quantized, we use a threshold-averaging
filter to smooth the decoded alpha plane.
Note: this option forces the decoding of alpha data in one pass, and
might slow the decoding a bit.
The new field in WebPDecoderOptions struct is 'alpha_dithering_strength'
(0 by default, means: off). Max strength value is '100'.
Change-Id: I218e21af96360d4781587fede95f8ea4e2b7287a
this change has the side-effect of using directory names in the
include, silencing a lint warning.
Change-Id: Ib91cf63a90534e32fadfa5c2372bfdb29f854d02
on ExUtilLoadWebP() failure no allocated memory will be returned, so
it's safe to exit immediately. additionally, any webp specific problems
will already have been reported as part of the call to
WebPGetFeatures().
broken since:
4a0e739 dwebp: move webp decoding to example_util
Change-Id: Ibc632015a1f52bae7f96d063252624123fa7c2da
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
useful for testing. Not listed in the man or README, since
it's only useful for testing the incremental decoding
(e.g. measuring the timing difference compared to non-incremental)
Change-Id: I8df8046e031d21006242babb5bcac09f8ff9f710
Doesn't work with WIC
+ redirect some info messages from stdout to stderr
+ fix the error reporting upon output-writing error
Change-Id: I92b8bd7a15e656a3f3cdfbf56299f024e39453f8
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
They went out of sync some time ago, and are
no longer really required since we have them
buildable from makefile.unix
Change-Id: Ica2dcf5c55f44365598f832f55204d123d7aa601
It will decode to raw (flat) YUV format, similar to what
cwebp can take as input. Makes the PSNR/SSIM calculation easier.
Change-Id: Iebfaedfc0bedc70c169b24ae4aabc701488d0644
retains the alpha channel rather than stripping it as with PPM.
display from ImageMagick can render the files
Change-Id: I4f3a5d332937e0aeaf4e3fbd214fdae3b5382fb8
- send errors to stderr
- send help to stdout
- add image size to webpmux -info output and send to stdout
- correct webpmux exit values
Change-Id: Ifd8e8493aab33a82765f7b7903cef345d96da9ae
spelling/indent/condense a few lines
removal/restriction of extern "C" usage
add const where applicable
Change-Id: Idd49b3498b1d7fc391724b4cde63706022217cb0
Gathers all DSP-related function (and SSE2 implementations).
Clean-up some unwanted symbolic dependencies so that webp_encode,
webp_decode and webp_dsp are truly independent libraries.
+ opportunistic clean-up:
* remove unneeded VP8DspInitTables(), now integrated in VP8DspInit()
* make consistent use of VP8GetCPUInfo() in the various DspInit() funcs
* change OUT macro to DST
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
(release|debug)-dynamic
These configurations will produce a dll in bin/ and an import lib under
lib/.
Currently the -noasm switch in the examples will be disabled for these
builds due to a dependency on VP8EncGetCPUInfo.
Change-Id: I2cbac0064f0e500698d14ffc03200791ca837090
When WEBP_HAVE_(JPEG|PNG) were undefined the stub functions would
produce warnings for unused parameters.
Change-Id: I79b2457c769d1f9382be834162de019c5427f94b
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
