This is particularly useful for multi-pass search (but not only),
to prevent the search from going over or below a reasonable threshold.
E.g.: 'cwebp -qrange 50 80 ...' will prevent any unreasonable degradation.
new cwebp option: -qrange min max
Change-Id: I59f394533535fc20b6996bc0895f4301476d5eff
Since people seem to write "2 ^ X" hoping that it means "1 << X", clang
recently added a warning for this pattern.
It incorrectly fires on this file. To suppress it, restructure the code
to be less clever. (Alternatively we could use "xor" instead of "^" or
write "0x2" instead of "2" but both seem worse.)
No intended behavior change.
Bug: chromium:995200
Change-Id: I64744345be5f5a8cd1f4aaeaf0982da239b378a7
For some exact resonance the over-quantization was exactly
compensating the under-quantization, leading to resonance
and strange patterns.
-> we special-handle the very flat blocks, hopefully for the
greater good (and not just the bad-resonance case).
For 'fast mode' (-m 3 or less), we just pay special attention
to the border of the image, where the oscillation / instability
usually starts. For the inner part of the image, since we're not
doing rd-opt, it's harder to fix anything.
Overall, on 'regular' images, the change is written the noise,
often leading to overall faster encoding (because of the short-cut).
BUG=webp:432
Change-Id: Ifaa8286499add80fd77daecf8e347abbff7c3a15
no change in object code
from clang-7 -fsanitize=implicit-integer-truncation
implicit conversion from type 'int' of value -16 (32-bit, signed) to
type 'uint8_t' (aka 'unsigned char') changed the value to 240 (8-bit,
unsigned)
Change-Id: Ia7cbaad247ab22b505b7f98b1247219c024f6db0
"implicit conversion from type 'uint32_t' (aka 'unsigned int') of value xxxxx (32-bit, unsigned) to type 'uint8_t' (aka 'unsigned char') changed the value to xx (8-bit, unsigned)"
and same with signed -> unsigned conversion with truncation.
Change-Id: I50cae41a9ce7edcfcc814cc3ee2556b927064f43
previously if the mappings allocation failed histo_queue->queue would be
uninitialized; split the conditionals
Change-Id: I1b50b987e734393893dc8a83a3f314522ccd0c83
It's safer to clip the passed param instead of doing 32b arithmetic
and clipping afterward.
Output is unchanged, but code no longer rely on UB.
Change-Id: Ia5b4de6e8863981753f1d17f062965a6a5da5bed
Move IsFlat to its own header. This allows it to continue to be
inlined. Using the RTCD and creating a distinct function slows down arm
builds.
flower mug
C 3.59 2.12
NEON 3.47 2.01
BUG=b/118740850
Change-Id: Id77e8f76d9e9790c498806e7070bbe37c10bc2e9
thresh is defined by FLATNESS_LIMIT_* which ranges from 2-10.
score_t is int64 which is a touch overkill.
Change-Id: I308bd440bf11643665d3642fe361495a257b6e52
The old code simply did not make sense.
The effect is that the pair would be popped from the
queue no matter what; as the queue is small, it does
not matter that much on the results.
But it will matter for a later CL.
Change-Id: If50c9fa9d7f3ac3c48bb7336d81479287d4944c4
(cherry picked from commit 485ff86fbb)
The old code simply did not make sense.
The effect is that the pair would be popped from the
queue no matter what; as the queue is small, it does
not matter that much on the results.
But it will matter for a later CL.
Change-Id: If50c9fa9d7f3ac3c48bb7336d81479287d4944c4
Also, histograms in a HistogramSet can be initialized all
at once.
Change-Id: Ibbfa6034dce58dca8bb9113487e2ae507222ce7d
(cherry picked from commit 6752904b2f)
When histograms are empty, it is easy to add them.
They should also not be considered when merging histograms
(it is a waste of CPU).
This does not change the compression performance,
just the speed.
Change-Id: I42c721ca0f9c5ea067e73b792aa3db6d5e71d01f
(cherry picked from commit decf6f6b87)
When histograms are empty, it is easy to add them.
They should also not be considered when merging histograms
(it is a waste of CPU).
This does not change the compression performance,
just the speed.
Change-Id: I42c721ca0f9c5ea067e73b792aa3db6d5e71d01f
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
(cherry picked from commit d77bf512bd)
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
(cherry picked from commit 978eec2507)
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
do_copy is a loop invariant, but based on a variable parameter; it would
only be extracted if Import was inlined.
Change-Id: Id5b4a1a4a83a4f2083444da4934e4c994df65b44
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
For large images overflowing the partition0, we re-do a number
of passes but were forgetting to reset the block_count[].
This was leading to incorrect summary.
+ some cosmetic fixes here and there
BUG=webp:355
Change-Id: Ie87158d7f177f8efdca429b146cfcd0e81652d2f
We can't predict if the quality is going to be below the threshold
eventually, so we might as well enable it always.
Change-Id: I30aedecc8c6d4daf159f6ef152697df0206d1e93
This fixes some color smearing due to heavy quantization.
This is only enabled for q <= 30 (cf ERROR_DIFFUSION_QUALITY)
Change-Id: I07e83a4d38461357a32c9e214f7eadc6db73baa9
only supported ones are: RGBA/BGRA/rgbA/bgrA (decoder)
as well as: WebPPictureImportRGB/RGBX/RGBA (encoder).
(note: extras/get_disto is affected too)
Change-Id: If6c4f95054ca15759c4e289fb3b4c352b3521c2c
(cherry picked from commit 6de20df02c)
