the incorrect bit was being extracted from the lossless bitstream header
causing the alpha flag in VP8X to be misreported. previously the
signature byte was ignored in the calculation of the offset.
since:
8ba1bf61 Stricter check for presence of alpha when writing lossless
images
BUG=webp:361
Change-Id: I7c618b5f01a37f5e4b799dee11a7949efaf88046
This patch fixes the compatibility for loop-count handling.
This aims at addressing the change in Chrome handling of loop-count
prior to M63.
Before M63: loop-count interpretation was aligned to GIF's behaviour in
Chrome, but incompatible with WebP's spec. In particular, you couldn't
loop exactly once.
Post-M63: loop-count in WebP is really the total number of loops. Gif2webp
will convert correctly from a GIF source by adjusting the loop count.
Note: The Chrome version can be retrieved from the User-Agent
string (chrome://version).
An M63 version will contain the pattern:
Chrome/63.x.xxxx.xx
for instance.
Change-Id: Ie6dc13227e6498f4d7af2f09247913648997648a
A command line tool to print out the chunk level structure of
WebP files along with basic integrity checks.
BUG=webp:330
Change-Id: Ic69f646f649abb655b1854621d99afedeed158d7
Encoder:
We were always using ExtraSamples=1, which means associated-alpha.
But we don't need the (lossy) excursion to rgbA format. We can save
the samples as RGBA directly, by changing ExtraSamples to '2'.
The TIFF encoder now checks the colorspace properly, to handle
premultiplied format as well as non-premultiplied.
Decoder:
The result of TIFFReadRGBAImageOriented() is always pre-multiply.
So, in case an alpha channel is present, we need to unmultiply it before
calling WebPPictureImportRGBA().
See:
https://www.itu.int/itudoc/itu-t/com16/tiff-fx/docs/tiff6.pdf (page 31)
and also http://www.asmail.be/msg0055469184.html
Change-Id: I3258bfdb0eb2e1a53d6c04414f55edb2926c938c
the sizes are already validated by CheckSizeForOverflow(), add casts to
size_t to avoid -Wshorten-64-to-32
Change-Id: Ida9102c2104f4a334a0ad16d6e01a12bedfd4eec
Passing the 'verbose' flag to DecodeWebP() wasn't mandated,
and was creating a forced dependency between imageio/ and examples/
Change-Id: Ib3d3f381a7b699df369a97cfb44360580422df11
it actually disables the disposal / blending method
and just displays the raw delta values.
Useful for debugging.
TODO: Outline the refreshed area with a drawn rectangle?
Change-Id: I6f8cddd0aad8b953cff78a693ae7e8c31def010c
The options are now:
-duration d -> set the whole animation to duration 'd'
-duration d,s -> set only frame 's' to duration 'd'
-duration d,s,e -> set only interval [s,d] to duration 'd'
+ style fix
Change-Id: I72e95282d520146f76696666f44280ad9506affa
this will force a constant duration for an interval of frames
in an animation.
Notes:
a) '-duration [...]' can be repeated as many times as needed.
b) intervals are taken into account in option order. If they overlap, values will be overwritten.
c) 'start' and 'end' can be omitted, but not the duration value.
d) 'end' can be equal to '0', in which case it means 'last frame'
e) single-image files are untouched (ie. not turned into an animation file).
Some example usage:
webpmux -duration 150 in.webp -o out.webp
webpmux -duration 33,10,0 in.webp -o out.webp
webpmux -duration 200,2 -duration 150,0,50 in.webp -o out.webp
Change-Id: I9b595dafa77f9221bacd080be7858b1457f54636
make this function return success/failure.
an empty map or out of bounds read is treated as an error.
BUG=webp:316
Change-Id: Ic8651836915ea4dd8e0dc81ca8d5d3f247be1ff8
This reverts commit f048d38d38.
the 'len' in Remap refers to the src[] not the colormap; this change
breaks valid files
BUG=webp:316
Change-Id: I1ed40075c2194df91d345cb6f29619b1f5cc96fc
Make WebPPictureDistortion() only compute distortion on A/R/G/B planes, not Y/U/V(A).
(not just for SSIM, but PSNR too).
This is to avoid problems with using SSIM on U/V channels.
If Y/U/V distortion is needed, one can always use WebPPlaneDistortion() individually.
Change-Id: If8bc9c3ac12a8d2220f03224694fc389b16b7da9
Also introduce an always-failing 'reader' for unknown formats.
So we don't have to check reader==NULL, code is more regular.
-> We can get read of specific ReadPNG(), ReadJPEG(), ... declaration and use.
Change-Id: I290759705420878f00c7223c726d4ad404afd9c4
- remove the inclusion of format_constants.h
- use incremental update of pointer, instead of arithmetic
(follow-up to e2affacc35)
Change-Id: I48420c8defc8d47339f54bc00e9da9617f08ab32
Mostly: avoid doing calculation like: ptr + j * stride
when stride is 'int'. Rather use size_t, or pointer increments (ptr += stride)
when possible.
BUG=webp:314
Change-Id: I81c684b515dd1ec4f601f32d50a6e821c4e46e20
DGifGetExtension() may successfully return, but the data pointer should
still be validated
BUG=webp:310
Change-Id: I6cfe617871fef2fe07887e5f48bb20f7ab7cfb35
quiets a -Wimplicit-function-declaration with some configurations of gcc
(-std=c99).
_POSIX_C_SOURCE is preferred over _BSD_SOURCE with newer versions of
glibc
Change-Id: I378bffb13ba52ff5c4bad1433090dcc387e5d507
