Set enc->prev_candidate_undecided_ as 0 when a frame is not chosen
as a possible keyframe, so that the dispose method can be
dispose-to-background.
Change-Id: If2899f5dbc06fb53705fb8240072ab6440a6de12
(cherry picked from commit 29fedbf58b)
When try_both_modes=0 (that is: -m 0 or -m 1), and the mode is i4,
we were still sometimes falling back to (unexplored, uninitialized) i16 mode,
which resulted in a enc/dec mismatch.
This was mainly occurring for large images (when bit_limit is low enough)
We disable the fall-back by disabling bit_limit using a large MAX_COST threshold.
Change-Id: I0c60257595812bd813b239ff4c86703ddf63cbf8
(cherry picked from commit 0a3838ca77)
the min-distortion was quite too low. And we were also
considering the fully skipped macroblocks (nz=0) in the stats.
We need to have at least *some* non-zero dc coeffs (nz=0x100XXXX).
Fix also two typos in StoreMaxDelta: the v0/v1 comparison was wrong,
and the DCs[] coeffs are actually already in ZigZag order.
Change-Id: I602aaa74b36f7ce80017e506212c7d6fd9deba1f
(cherry picked from commit e4cd4daf74)
some multiplies here and there needed some extra checks
and error reporting. Even if width * height is guaranteed
to be < 2**32, we were multiplying by num_channels and
triggering a 32b overflow.
Some multiplies were not using size_t or uint64_t, additionally.
Change-Id: If2a35b94c8af204135f4b88a7fd63850aa381bbf
(cherry picked from commit 1c36440094)
max_i4_header_bits_ could drop to zero for difficult image and trigger
a loop. Surprisingly, StatLoop() didn't have this bug.
Change-Id: Idc0f9eadef30a2b2f02041b994f25def30901e36
(cherry picked from commit 21e7537abe)
Pick the mode with the smallest alpha.
It only affects m0, in which case the mode decision is not re-examined
later in VP8Decimate(). Tests on some natural content png images show
PSNR increase as well as visual quality improvement.
Change-Id: Iea997e718cd7477160fa05eb7cfb35f4cec2fa9a
(cherry picked from commit 1377ac2ec1)
avoids int rollover when working with large input
BUG=webp:312
Change-Id: I6ad9f93b6c4b665c559bff87716a7b847f66a20d
(cherry picked from commit 342e15f0ce)
avoids int rollover when working with large input
BUG=webp:312
Change-Id: I2881bec2884b550c966108beeff1bf0d8ef9f76b
(cherry picked from commit 1147ab4ee7)
avoids int rollover when working with large input
BUG=webp:312
Change-Id: I693cbb295df9cf94aa89294b19c0496bdbe84d18
(cherry picked from commit de9fa5074e)
avoids int rollover when working with large input
BUG=webp:312
Change-Id: I3d7b689be8d5751248a82d1021243d80d3f67203
(cherry picked from commit deb1b83199)
This is essentially a revert of a3611513d2
and cfbcc5ece0.
Here is what happened: there was a corruption bug that eventually
got fixed by 0174d18d8b.
But before finding the root, a3611513d2
and cfbcc5ece0 hid the bug
by not imposing length of 1 when it was actually 2 or 3 (which does help
compression as a litteral is more efficient than an offset and a length
of size 2 or 3).
Change-Id: I6f18fc1f583a51ac9d8aab2508458264047cd493
this function can be called not to decode pixels, but simply
to finish processing (through process_func()) the already decoded
pixels.
Change-Id: I80485e92e3c47f0aa3389476dcb82745a243fc4a
The optimization for (len != MIN_LENGTH) actually only holds for
(len > MIN_LENGTH) but (len < MIN_LENGTH) can now happen as len can
be changed in the loop before.
Change-Id: I3f9f91a540206c80385c5fba96c3d64ab9536752
On the non-fast path (use_8b_decode_=0) for decoding the alpha-mask,
we could end up requesting ApplyInverseTransform() with more rows
to process than NUM_ARGB_CACHE_ROWS. This could only happen on the
very last bottom rows of the image.
* ProcessRows() doesn't need to be fixed, since we never request more
than NUM_ARGB_CACHE_ROWS rows. Added an assert for that.
* the use_8b_decode_=1 case doesn't use argb_cache_, but rather does
the palette-decoding call directly. So, no problem here too.
Only the generic (and rather rare) case of calling ExtractAlphaRows()
was affected.
Change-Id: I58e28d590dcc08c24d237429b79614abcef1db7c
This is getting back to the old behavior which is actually better for
compression and speed with the latest patches.
Change-Id: I35884bab02589297c25d6e1e66dc5f13e05f7aa7
This was defined (slightly differently) at two places. Created a common
method and moved to utils/utils.[hc].
Change-Id: I66c3ac6dea24e0cd2c0eaa5440f3142b4dbbe23b
we don't need to store the resulting histogram, so no need to
call HistogramAddEval().
Allows some signature simplifications...
Change-Id: I3fff6c45f4a7c6179499c6078ff159df4ca0ac53
In case where the same offset is found in consecutive pixels,
the cost computation from one pixel can be re-used for the next.
Change-Id: Ic03c7d4ab95f3612eafc703349cfefd75273c3d7
