the interpretation of a 0 duration depends on the implementation;
merging of multiple frames isn't guaranteed, some may enforce a minimum
duration.
BUG=webp:380
Change-Id: Idf592049d2092e4cc5cfb2e4c59ddbc91bd52f9c
this internalizes the init checks and provides stronger synchronization
with pthreads when available while still allowing VP8GetCPUInfo to be
modified (mostly for testing purposes). windows is left as is since a
critical section or mutex would cause a leak.
Change-Id: Ieb997e014f2805c0ae39c16f13337663521356f4
Control Flow Integrity [1] indirect call checking verifies that function
pointers only call valid functions with a matching type signature. This
change eliminates function pointer casts that were causing cfi-icall
failures.
[1] https://www.chromium.org/developers/testing/control-flow-integrity
BUG=chromium:827826
Change-Id: I5db021d06390a6cefd670fdd2f0d34c9e530465e
this is consistent with web browser behavior as well as various
transcoding tools (ffmpeg, gif2apng, etc).
also: update anim_diff to account for this new behaviour.
BUG=webp:379
Change-Id: I70cc72a6b401ef32b73cd182a3f12d993d495bf4
Output is <.1% difference in size, randomly.
Speed is 30-50% faster (-m 0 -sharp_yuv).
It also gives the exact same output on ARM and x86, because floats
are no longer used.
Change-Id: Id0f0aa748cc4fc0b82bac1fc5ca954775a0a1b7c
this quiets a -Wclobbered warning on const has_alpha under gcc-7 and
brings the variables closer to their first use.
Change-Id: I8a24f275b7ff34a94d47b576bcf276dbedac2121
do_copy is a loop invariant, but based on a variable parameter; it would
only be extracted if Import was inlined.
Change-Id: Id5b4a1a4a83a4f2083444da4934e4c994df65b44
Apply gamma correction to the decoded RGB values.
This handles corner cases where the PNG file doesn't have
a standard 1/2.2 gamma value.
BUG=webp:369
Change-Id: I9907b6e2c458002de7c26d0b9e416278cca33990
for q<=98, we always enable error diffusion.
+ reduce storage 2x by using int8_t
+ make the error diffusion more robust
BUG=webp:340,308
Change-Id: I0608df839ff7b64d6843005a0f81d2577143af9e
* regarding alpha_data_ used for testing.
alpha_data_!=NULL is as close a good test as we'll get.
* regarding filter-strength / sharpness forcing
no practical use (can be done during encode cycles,
for experimentation)
* regarding a 'less-complex' filtering:
no practical use so far. Next version!
Change-Id: If2dfff5818552a7d3e7c23ac08d64fe6d270229c
