The mode's bits were not taken into account, which is ok for most of cases.
But in case of super large image, with 'easy' content, their overhead starts
mattering a lot and we were omitting to optimize for these.
Now, these mode bits have their own lambda values associated, limiting
the jerkiness. We also limit (for -m 2 only) the individual number of bits
to something that will prevent the partition 0 overflow.
removed the I4_PENALTY constant, which was a rather crude approximation.
Replaced by some q-dependent expression.
fixes issue #289
Change-Id: I956ae2d2308c339adc4706d52722f0bb61ccf18c
This is in preparation for some SSE2 code.
And generally speaking, the whole SSIM code needs some
revamp: we're not averaging the SSIM value at each pixels
but just computing the overall SSIM value once, for the whole
plane. The former might be better than the latter.
Change-Id: I935784a917f84a18ef08dc5ec9a7b528abea46a5
setting all transparent pixels to black rather than the "flatten" method.
0.3% smaller filesize on the 1000 PNGs if alpha cleanup is used (before: 18685774, after: 18622472)
Change-Id: Ib0db9e7ccde55b36e82de07855f2dbb630fe62b1
Note that ALIGN_CST is still kept different in dec/frame.c for now,
because the values is 31 there, not 15. We might re-unite these two
later.
Change-Id: Ibbee607fac4eef02f175b56f0bb0ba359fda3b87
had to rename few structs.
-> we can now include both vp8i.h and vp8enci.h without naming
conflicts.
Change-Id: Ib41b498f1b57aab3d6b796361afc45210ec75174
The MIPS code for cost is not updated yet, that's why i keep Residual::*cost
around for now. Should be removed in favor of *costs later.
Change-Id: Id1d09a8c37ea8c5b34ad5eb8811d6a3ec6c4d89f
removes circular dependency between dsp and enc.
since:
a987fae MIPS: dspr2: added optimization for function GetResidualCost
Change-Id: Ifeb8fc02de89e2ba982ed7ffacd925d649bfec3c
we don't need to store the whole distribution in order to compute the alpha
Later, we can incorporate the max_value / last_non_zero bookkeeping
in SSE2 directly.
Change-Id: I748ccea4ac17965d7afcab91845ef01be3aa3e15
this is a first step to unifying encoding/decoding cache stride
and possibly sharing the prediction functions in dsp/
With this layout, there's a little (~7%) space lost with unused samples.
But no speed change was observed.
Change-Id: I016df8cad41bde5088df3579e6ad65d884ee711e
Compared to previous mode it gives another 10-30% improvement in compression keeping comparable PSNR on corresponding quality settings.
Still protected by the WEBP_EXPERIMENTAL_FEATURES flag.
Change-Id: I4821815b9a508f4f38c98821acaddb74c73c60ac
This compresses the uimage using lossless compression and controlable
decimating pre-process.
Code is under WEBP_EXPERIMENTAL_FEATURE while it's being experimented with.
Change-Id: I8b7f4cfcc3c6afc52a556102842bdbb045ed5ee8
also changed the token-page layout a little bit to remove
a not-needed field.
This reduces the number of malloc()/free() calls substantially
with minimal increase in memory consumption (~2%).
For the tail of large sources, the number of malloc calls goes
typically from ~10000 to ~100 (e.g.: bryce_big.jpg: 22711 -> 105)
Change-Id: Ib847f41e618ed8c303d26b76da982fbc48de45b9
(and ~2-3% on ARM)
We don't need to store cost/score for each node, but only for
the current and previous one -> simplify code and save some memory.
Also made the 'Node' structure tighter.
Change-Id: Ie3ad7d3b678992b396242f56e2ac387fe43852e6
kLevelsFromDelta[sharpness][delta] is an inverse look-up table
that tells the minimum filtering strength needed to trigger the
filtering of a step with amplitude 'delta'. We use this table
in various situations:
a) when computing the initial (/global) filtering
strength for each segment. We look at the quantization
step and deduce the proper filtering strength needed
to result this quantization noise (talking the -f option
into account).
b) during intra16 calculation, when a block ends up
very empty (only DC coeffs are non-zero, all ACs have
vanished). We'll rely on the in-loop filtering to
restore the smoothness (if the source was gradient-like
smooth. That's why we look at the distortion too before
triggering the filtering).
Step b) goes _in addition_ to a), potentially raising
the filtering strength if blockiness is likely.
Change-Id: Icaeca93ef21da195b079e6587a44d9edfc8e9efa
* fix VP8FixedCostsI4ÆÅ table
(the constant cost '211' was erronenously included)
* use the rd-score for '211' correctly (calling SetRDScore() for good)
* count partition0 bits separately during rd-opt
No meaningful difference in rd-curve.
Change-Id: I6c49a150cf28928d9a92c32fff097600d7145ca4
When -mt is used, the analysis pass will be split in two
and each halves performed in parallel. This gives a 5%-9% speed-up.
This was a good occasion to revamp the iterator and analysis-loop
code. As a result, the default (non-mt) behaviour is a tad (~1%) faster.
Change-Id: Id0828c2ebe2e968db8ca227da80af591d6a4055f
* move yuv_in_/out_* scratch buffers to iterator
* add y_top_/uv_top_ shortcuts in iterator
That's ~3k of stack size instead of heap.
But it allows having several iterators work in parallel.
Change-Id: I6a437c0f2ef1e5d398c1d6a2fd4974fa0869f0c1
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
(cherry picked from commit d640614d544453ce14e2bbeeef8f33c78c8b09fd)
Saturation was done on input coeff, not quantized one.
This saturation is not absolutely needed: output of FTransformWHT
is in range [-16320, 16321]. At quality 100, max quantization steps is 8,
so the maximal range used by QuantizeBlock() is [-2040, 2040].
But there's some extra bias (mtx->bias_[] and mtx->sharpen_[]) so
it's better to leave this saturation check for now.
addresses issue #145
Change-Id: I4b14f71cdc80c46f9eaadb2a4e8e03d396879d28
using token-buffer (that is: slightly more memory. O(output_size))
This change is ON by default. To return to previous behaviour, use
'cwebp -low_memory' or set config.low_memory to true.
Side-effect of this new mode: it forces 1 partition only (which was
default anyway), and makes some statistics about the bitstream
no longer available. cwebp will no longer report 'intra4-coeffs', etc.
This mode also doesn't work (yet) with multi-pass, and -low_memory
is currently forced for multi-pass.
also: reversed the flag: USE_TOKEN_BUFFER -> DISABLE_TOKEN_BUFFER
also: fixed the kAverageBytesPerMB estimate
Change-Id: I4ea80382038d6df4309663e0cb7bd88d9bca9cf1
