For some GIF images, the first frame is missing the corresponding
graphic control extension. For such cases, we were never calling
GetBackgroundColor(), and default background color value (white) was being used
incorrectly.
So, we call GetBackgroundColor() when we encounter the first image
descriptor instead, to make sure that it is always called.
Change-Id: I00fc8e943d8a0c1578dcd718f3e74dec7de4ed61
* try to avoid trailing '.'
* rationalize capitalization
missed in:
0a8b886 dust up the help message
Change-Id: I6f80736cc8a2ff4f185f63d463a57d5bbf88a0db
previously, the final canvas size was adjusted tightly from the
animation frames. Now, it can be specified separately (to be larger, in particular).
calling WebPMuxSetCanvasSize(mux, 0, 0) triggers the 'adjust tightly' behaviour.
This can be useful after calling WebPMuxCreate() if further image addition
is expected.
-> Fixed gif2webp accordingly.
also: made WebPMuxAssemble() more robust by systematically zero-ing WebPData.
Change-Id: Ib4f7eac372cf9dbf6e25cd686a77960e386a0b7f
Similarly to Chrome, we then use the first sub-rectangle
to set the canvas size.
Also: add check for too-large GIF dimensions (>MAX_CANVAS_SIZE)
Change-Id: Idce55f1e6f6982a8f0e082aac540e16b530e023e
We align with Blink/Chromium code by:
- checking for ANIMEXTS1.0 signature too
- using ByteCount >= 3 instead of requiring ByteCount==3
Change-Id: Idc484ca62878517df3dccb1fdb3bb45104a5e066
see: http://odur.let.rug.nl/kleiweg/gif/netscape.html
this change has the side-effect of using directory names in the
include, silencing a lint warning.
Change-Id: Ib91cf63a90534e32fadfa5c2372bfdb29f854d02
* allow reading from stdin for dwebp / vwebp
* allow writing to stdout for gif2webp
by introducing a new function ExUtilReadFromStdin()
Example use: cat in.webp | dwebp -o - -- - > out.png
Note that the '-- -' option must appear *last*
(as per general fashion for '--' option parsing)
Change-Id: I8df0f3a246cc325925d6b6f668ba060f7dd81d68
this would require a PRIuS or similar macro for proper platform
compatibility (Visual Studio for instance would be variants of %lu)
Change-Id: I2b9fcb1639db024775fb47dbcf79a2240f3d98f2
This is to discourage generation of animated WebP images with ICC
profile, as
the real-world use-case for such images is rare at best.
Output of ICC/XMP metadata is now controlled by the '-metadata' option.
Change-Id: I8e3e29878c32bf46cbc661f50661bac602603c43
When '-mixed' option is given, each frame would be heuristically chosen
to be
encoded using lossy or lossless compression.
The heuristic is based on the number of colors in the image:
- If num_colors <= 31, pick lossless compression
- If num_colors >= 194, pick lossy compression
- Otherwise, try both and pick the one that compresses better.
Change-Id: I908c73493ddc38e8db35b7b1959300569e6d3a97
This is to conform to man/gif2webp.1
Earlier, one needed to give both '-kmin 0' and '-kmax 0' for this to
work.
Also, suppress further warnings for kmin = 0 and/or kmax = 0 case.
Change-Id: I6f5eeb609aeffc159d0252a40a5734162f7e4e7d
Specifically:
- Merge OptimizeAndEncodeFrame with WebPFrameCacheAddFrame: they use the same
if-else structure.
- Move maintenance of 'prev_canvas' and 'curr_canvas' to util.
- Move ReduceTransparency() and FlattenPixels() calls to SetFrame(): This is in
preparation for the next patch: which will try try lossless encoding for
each frame, even when '-lossy' option is given.
- Make most methods static inside util.
No changes to output expected.
Change-Id: I1f65af25246665508cb20f0f6e338f9aaba9367b
quite rarely, it gives a different output
then without the HINT, but that's often for
a smaller size (tested with default -m and -m 6)
Change-Id: I51d221ab61f8e007983325031345728e8d80b241
helps during lossless compression.
10% average saving, but that's mostly on what was previously
'difficult' cases, where the gain is ~30-50% actually.
Non-difficult cases are mostly unchanged.
Tested over ~7k random web gifs.
Change-Id: I09db4560e4ab09105d1cad28e6dbf83842eda8e9
We reduce transparency by turning some transparent pixels into
corresponding RGB values from previous canvas.
This improves compression by about 23%.
Change-Id: I02d70a43a1d0906ac09a7e2dc510be3b2d38f593
...and make gif2webp and vwebp compile without them.
Makefile.vc still to be updated...
Meanwhile the CL environment variable can be supplemented with
set CL=/DWEBP_HAVE_GL /IC:\opt\freeglut\include
Change-Id: I37a60b8c32aafd125bffa98b6cc9f57c022ebbd0
We use the 'do not blend' option for creating independent frames.
We also mark the already independent frames as 'do not blend'.
This bounds the maximum number of frames that need to be decoded to
decode a given frame, thus leading to a much better decoding performance.
Change-Id: I7cef98af2b53751ec36993fd2bd54f7f4c4aad2b
This is to ensure that the output WebP image is consistent with original
GIF when displayed against any background color.
Change-Id: I14218848153eb40358aa4ce331b2543d2fc2e86c
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
When transparent color index and background color index are same,
we should set background color to 0x00ffffff (transparent).
For this, we delay setting the background color until we have read the
first frame.
Change-Id: I443609b9c7697a2b94a66992460cff8465b3c127
