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
Change-Id: I36d3765e94d2b5529b321c186ccee1744785c5b3
fixes:
error: ISO C++ forbids forward references to 'enum' types
since:
28d25c8 replace 'typedef struct {} X;" by "typedef struct X X; struct X {};"
For low-color images, it may be better to not use color-palettes.
Users should treat this as one another hint (as with Photo &
Picture) and another parameter for tuning the compression density.
The optimum compression can still be obtained by running (outer loop)
compression with all possible tunable parameters.
Change-Id: Icb1a4face2a84774e16e801aee4a8ae97e232e8a
also relocate user_data from WebPAuxStats to the WebPPicture struct to
make clearing easier while placing it closer to the progress hook with
which it's used.
prior to this change some spurious lossless data could be reported in
the lossy (sans alpha) encoding case. additionally user_data could be
lost during lossless encoding.
Change-Id: I929fae3dfde4d445ff81bbaad51445ea586dd80b
* Extend AuxStats with new fields
it's slightly ABI-incompatible, but i guess it's ok for 0.1.99+
I expect to add more stats later, possibly (predictor stats, etc.)
* Have cwebp report the features used by lossless
compression (either for alpha or full lossless coding)
* Print the PSNR for alpha (useful in case of -alpha_q)
* clean-up alpha.c signatures
+ misc cleanup (added const '* const ptr', etc.)
Change-Id: I157a21581f1793cb0c6cc0882e7b0a2dde68a970
* commit 'v0.1.99': (39 commits)
Update ChangeLog
add extra precision about default values and behaviour
header/doc clean up
Makefile.vc: fix webpmux.exe *-dynamic builds
remove INAM, ICOP, ... chunks from the test webp file.
harmonize authors as "Name (mail@address)"
makefile.unix: provide examples/webpmux target
update NEWS
README: cosmetics
man/cwebp.1: wording, change the date
add a very crude progress report for lossless
rename 'use_argb_input' to 'use_argb'
add some padding bytes areas for later use
fixing the findings by Frederic Kayser to the bitstream spec
add missing ABI compatibility checks
Doc: container spec text tweaks
add ABI compatibility check
mux.h: remove '* const' from function parameters
encode.h: remove '* const' from function parameters
decode.h: remove '* const' from function parameters
...
Conflicts:
src/mux/muxinternal.c
Change-Id: I635d095c451742e878088464fe6232637a331511
Put emphasis on RGBA decoding instead of RGB/BGR
Clarify doc at some rough spots
Misc typo fix and cosmetics
Change-Id: Ic5fcfcc5bf4d612c5de23b0a5499f1fadde55bfe
- WEBP_MUX_INVALID_PARAMETER: was used only at one place, and that too
should actually be an assert().
- WEBP_MUX_ERROR: was never used.
Change-Id: I8883cb4dfae7a7918507501f21fced0c04dda36a
minor revision shouldn't matter, we only check major revision number.
Bumped all version numbers so that incompatibility starts *now*
Change-Id: Id06c20f03039845ae4cfb3fd121807b931d67ee4
the VP8 decode functions do not need to be public; only
GetInfo/CheckSignature need to be marked extern as they're used by
libwebpmux.
Change-Id: Id9ab4d6166b0271cf5d04563c6dac1fcc84adbdc
- Match offsets, duration, width/height for frames/tiles and enforce
some constraints.
- Note that this also means using 'int's instead of 'uint32_t's for
16-bit and 24-bit fields.
Change-Id: If0b229ad9fce296372d961104aa36731a3b1304b
Adds new methods WebPPictureARGBToYUVA() and WebPPictureYUVAToARGB()
Depending on the value of picture->use_argb_input,
the main call WebPEncode() will convert appropriately.
Note that both conversions are lossy, so it's recommended to:
* use YUVA input for lossy compression (picture->use_argb_input=0)
* use ARGB input for lossless compression (picture->use_argb_input=1)
Change-Id: I8269d607723ee8a1136b9f4999f7ff4e657bbb04
* add a real proper pointer for holding memory chunk pointer
(instead of using y and argb fields)
* polish the doc with details
* add a WebPPictureView() that extract a view from a picture
without any copy (kind of a fast-crop).
* properly snap the top-left corner for Crop/View. Previously,
the luma position was not snapped, and was off compared to the chroma.
Change-Id: I8a3620c7f5fc6f7d1f8dd89d9da167c91e237439
'Set' and 'Get' methods for images take/return a bitstream as input,
instead of separate 'image' and 'alpha' arguments.
Also,
- Make WebPDataCopy() a public API
- Use WebPData for storing data in WebPChunk.
- Fix a potential memleak.
Change-Id: I4bf5ee6b39971384cb124b5b43921c27e9aabf3e
