This fixed a conflict introduced by the change of adding 8x8 intra
prediction modes. The 8x8 intra prediction mode code assumed the
use of 4x4 transform, and causes encoder crashes when the codec is
configured with --enable-t8x8.
Change-Id: I00cc94df63e9725377ffba9eb51be6b77fe3fcf9
Added code to support 256 index steps instead of 128 but disabled for now.
Replace hard wired table vp8cx_base_skip_false_prob[128]
Observed Qindex problem with setting minimum loop filter value.
(Experiment code using real Q in place but for now just returning 0. This has a big
beneficial effect on some clips, particularly waterfall which shows 5% ssim gain)
Change-Id: I2f7117de8adc1797164c106aa13effc900a1467e
This commit removed the macro CONFIG_I8X8, which was used to indicate
the 8x8 intra prediction experiment, made the change fully merged in.
Change-Id: Iafa4443781ce6e83f5591c12ba615a0e92ce0ea0
vp8_mode_contexts[] is an entropy table used to code inter mode
choices. It was a fixed constant table. This commit made the entropy
context adaptive. Tests on derf set showed very good consistent gains
on all metrics: avg psnr .47%, overall psnr .46% and ssim .40%.
http://www.corp.google.com/~yaowu/no_crawl/newModeContext.html
Change-Id: Ia62b14485c948e2b74586118619c5eb2068b43b2
This patch introduces the concept of dual inter16x16 prediction. A
16x16 inter-predicted macroblock can use 2 references instead of 1,
where both references use the same mvmode (new, near/est, zero). In the
case of newmv, this means that two MVs are coded instead of one. The
frame can be encoded in 3 ways: all MBs single-prediction, all MBs dual
prediction, or per-MB single/dual prediction selection ("hybrid"), in
which case a single bit is coded per-MB to indicate whether the MB uses
single or dual inter prediction.
In the future, we can (maybe?) get further gains by mixing this with
Adrian's 32x32 work, per-segment dual prediction settings, or adding
support for dual splitmv/8x8mv inter prediction.
Gain (on derf-set, CQ mode) is ~2.8% (SSIM) or ~3.6% (glb PSNR). Most
gain is at medium/high bitrates, but there's minor gains at low bitrates
also. Output was confirmed to match between encoder and decoder.
Note for optimization people: this patch introduces a 2nd version of
16x16/8x8 sixtap/bilin functions, which does an avg instead of a
store. They may want to look and make sure this is implemented to
their satisfaction so we can optimize it best in the future.
Change-ID: I59dc84b07cbb3ccf073ac0f756d03d294cb19281
Resolved or factored out some further issues with Q index.
Put in a 3rd order polynomial instead of less accurate power function
as the best fit on gf and kf boost adjustment.
Added avg_q value to use instead of ni_av_qi.
Compute segment delta Q values based on avg_q.
Fixed bug in adjust_maxq_qrange().
The extended range Q on the derf set, using standard data rates
(which do not extend high enough to get big benefits) still show
a shortfall of between 0.5 and 1% though so there would appear to
be further issues that need to be tracked down.
Change-Id: Icfd49b9f401906ba487ef1bef7d397048295d959
This commit enabled the usage of 8x8 intra prediction modes on inter
frames. There are a few TODO items related to this: 1)baseline entropy
need be calibrated; 2)cost of UV need to be done more properly rather
than using decision only relying on Y; 3)Threshold for allowing picking
8x8 intra prediction should be lowered to lower than the B_PRED.
Even with all the TODOs, tests showed consistent gain on derf set ~0.1%
(PSNR:0.08% and SSIM:0.14%). It is assumed that 8x8 intra prediction
will help more on large resolution clips, especially with above TODOs
addressed.
Change-Id: I398ada49dfc32575cfab962a569c2885111ae3ba
Fixed some further QIndex related issues and replaced some tables
(eg zbin and rounding)
Also Added function (currently disabled by default) to populate the
main AC and DC quantizer tables. Using the original AC range the
resulting computed DC values give behavior broadly comparable
on the DERF set. That is not to say that the equations will hold good
over a more extended range. The purpose of this code is to make it
easier to experiment with further alterations to the Q range and distribution
of Q values plus the relative weights given to AC and DC.
The function find_fp_qindex() ensures that changes to the Q tables
are reflected in the value passed in to the first pass code.
Slight experimental adjustment to static segment Q offset.
Change-Id: I36186267d55dfc2a3d565d0cff7218ef300d1cd5
Fixed bug in firspass.c call to vp8_initialize_rd_consts()
This was passing in vp8_dc_quant(cm->base_qindex, cm->y1dc_delta_q)
instead of (cm->base_qindex + cm->y1dc_delta_q).
It just so happens that for the value 26 used for cm->base_qindex in the
unextended Q case, the two give similar results. However, when using
the extended Q range the two are very different.
Also added more stats output and partly disabled another broken feature.
Change-Id: Iddf6cf5ea8467c44b7c133f38e629f6ba6f2581e
This is an experiment to include a mv contribution from last frame to
nearest and near mv definition. Initial test showed some small though
consistent gain.
latest patch slightly better result ~.13%-~.18%.
TODO: the entropy used to encode the mode choice, i.e. the mv counts
based conditional distribution of modes should be re-collected to
reflect this change, it is expected that there is some further gain
from that.
Change-Id: Ief1e284a36d8aa56b49ae5b360c91419ec494fa4
This commit resolves further QIndex look up tables to facilitate
experimentation with the quantizer range.
In some cases rather than remove the look up tables completely
I have created functions that are called once to populate them
using a formulaic approach base on the actual quantizer.
The use of these functions based on best fit of data from the original
tables does affect the results on some clips but across the derf test
set the effect was broadly neutral.
Change-Id: I8baa61c97ce87dc09a6340d56fdeb681b9345793
One of the problems arising when tweaking or adjusting the quantizer
tables is that there are a lot of look up tables that depend on the QINDEX.
Any adjustment to the link between QINDEX and real quantizer therefore tends
to break aspects of for example the rate control.
In this check in I have replaced several of the look up tables with functions that
approximate the same results as the old Q luts but use a formulaic approach
based on real Q values rather than QIndex. This should hopefully make it easier
to experiment with changes to the Q tables without always having to go through
and hand optimize a set of look up tables. Once things stabilize we may choose
to re-instate luts for the sake of performance.
Patch 2:
Addressed Ronald's comments.
vp8_init_me_luts() Added so luts only initialized once.
Change-Id: Ic80db2212d2fd01e08e8cb5c7dca1fda1102be57
For ease of testing and merging experiments I have
removed in line code in encode_frame() that assigns
MBs to be t8x8 or t4x4 coded segments and have
moved the decision point and segment setup to
the init_seg_features0 test function.
Keeping everything in one place helps make sure
for now that experiments using segmentation are
not fighting each other.
Also made sure mode selection code can't choose 4x4
modes if t8x8 is selected.
Patch2: In init_seg_features() add checks
for SEG_LVL_TRANSFORM active.
Change-Id: Ia1767edd99b78510011d4251539f9bc325842e3a
Bug fix to logic in vp8_pick_inter_mode() and
vp8_rd_pick_inter_mode().
The block on the use of segment features
for the cm->refresh_alt_ref_frame case
was just for testing and is not correct.
The special case code for alt ref can
be re-enabled as an else clause.
Change-Id: Ic9b57cdb5f04ea7737032b8fb953d84d7717b3ce
Initial attempt at using new segment feature signaling
to indicate 4x4 or 8x8 transform.
needs --enable-experimental --enable-t8x8
Note this is work in progress.
Change-Id: Ib160d46a5d810307bfcbc79853ce1a65b5b870b7
No change to functionality or output.
Updates to the segment feature data structure now all done
through functions such as set_segdata() and get_segdata()
in seg_common.c.
The reason for this is to make changing the structures (if needed)
and debug easier.
In addition it provides a single location for subsequent addition
of range and validity checks. For example valid combination of
mode and reference frame.
Change-Id: I2e866505562db4e4cb6f17a472b25b4465f01add
Removal of configure #ifdefs so that segment features
always available. Removal of code supporting old
segment feature method.
Still a good deal of tidying up to do.
Change-Id: I397855f086f8c09ab1fae0a5f65d9e06d2e3e39f
Modify reference frame segmentation so that ONE or MORE
reference frames may be marked as a available for a given
segment.
Fixed bugs relating to segment coding of INTRA and some
INTER modes at the segment level.
Modified Q boost for static areas based on ambient average Q.
Strong results now on clips with significant static areas.
(some data points in derf set as high as 9% and some static &
slide show type content in YT set > 20%)
Change-Id: Ia79f912efa84b977f35a23683ae3643251e24f0c
This quite large check in includes the following:
Merge in some code from Ronald (mbgraph.c) that scans a Gf/arf group.
This is used as a basis for a simple segmentation for the normal frames
in a gf/arf group. This code also uses satd functions from Yaowu.
Adds functionality for coding the latest possible position of an EOB for
blocks in the segment. (Currently 0-15 only, hence just for 4x4 dct).
Where the EOB position is 0 this acts like "skip" and the normal coding
of skip at the per mb level is disabled.
Added functions (seg_common.c) for setting and reading segment feature
elements. These may want to be optimized away at some point but while the
mecahnism is in a state of flux they provide a single location for making
changes and keep things a bit cleaner.
This is still proof of concept code. Currently the tested feature set:-
Quantizer,
Loop Filter level,
Reference frame,
Prediction Mode,
EOB end stop.
TBD:-
Add functions for setting and reading the feature data with range
and validity checking.
Handling of signed and unsigned feature data. At the moment all is assumed
to be signed and a sign bit is coded but many cannot be negative.
Correct handling of EOB feature with intra coded blocks.
Testing/trapping of legal/illegal ref frame and mode combinations.
Transform size switch plus merge and test with 8c8 DCT work
Merge and test with Sumans Segmenation coding optimizations
Change-Id: Iee12e83661c7abbd1e0ce6810915eb4ec35e2d8e
Proof of concept test code that encodes mode and reference
frame data at the segment level.
Decode-able bit stream but some issues not yet resolved.
As it this helps a little on a couple of clips but hurts on most as
the basis for segmentation is unsound.
To build and test, configure with
--enable-experimental --enable-segfeatures
Change-Id: I22a60774f69273523fb152db8c31f4b10b07c7f4
This commit added a 3 bit index to the bitstream, the index is used to
look into the intra mode coding entropy context table. The commit uses
the mode stats to calculate the cost of transmitting modes using 8
possible entropy distributions, and selects the distribution that
provides the lowest cost to do the actual mode coding.
Initial test show this provides additional .2%~.3% gain over quantizer
adaptive intra mode coding. So the adaptive intra mode coding provides
a total of .5%(psnr) to .6% gain(ssim) combined for all-key-encoding
To build and test, configure with
--enable-experimental --enable-qimode
Change-Id: I7c41cd8bfb352bc1fe7c5da1848a58faea5ed74a
Patch 1 to Patch 3 is an initial implementation of 8x8 intra prediction
modes, here are with the following assumptions:
a. 8x8 has 4 prediction modes DC, H, V and TM
b. UV 4x4 block use the same mode as corresponding 8x8 area
c. i8x8 modes are enabled for key frame only for now
Patch 4:
d. removed debug code from previous patches
Patch 5:
e. added stats code to collect entropy stats and further cleaned up
Patch 6:
f. changed mode stats code to collect finer stats of modes
Patch 7:
g. normalized i8x8 modes distribution to total at 256 (8bits).
Patch 8:
h. fixed a bug in decoder and removed debug printf output.
Patch 9:
i. more cleanups to address paul's comment
Patch 10:
j. messy rebase/merges to bring the commit up to date.
Tests on HD clips encoded with all key frame showing consistent gain
on all clips and all metrics:~0.5%(psnr) and 0.6%(ssim):
http://www.corp.google.com/~yaowu/no_crawl/i8x8hd_allkey_fixedq.html
To build and test, configure with:
--enable-experimental --enable-i8x8
Change-Id: I9813fe07ae48cab5fdb5d904bca022514ad01e7f
for SPLITMV and B_PRED modes. Modified code to use the bmi
found in mode_info_context instead of BLOCKD. On the decode
side, the uvmvs are calculated only when required, instead of
every macroblock. This is WIP. (bmi should eventually be
removed from BLOCKD)
Small performance gains noticed for RT encodes and decodes.(VGA)
Change-Id: I2ed7f0fd5ca733655df684aa82da575c77a973e7
This change implemented same idea in change "Preload reference area
to an intermediate buffer in sub-pixel motion search." The changes
were made to vp8_find_best_sub_pixel_step() and vp8_find_best_half
_pixel_step() functions which are called when speed >= 5. Test
result (using tulip clip):
1. On Core2 Quad machine(Linux)
rt mode, speed (-5 ~ -8), encoding speed gain: 2% ~ 3%
rt mode, speed (-9 ~ -11), encoding speed gain: 1% ~ 2%
rt mode, speed (-12 ~ -14), no noticeable encoding speed gain
2. On Xeon machine(Linux)
Test on speed (-5 ~ -14) didn't show noticeable speed change.
Change-Id: I21bec2d6e7fbe541fcc0f4c0366bbdf3e2076aa2
There were some situations that the start motion vectors were
out of range. This fix adjusted range checks to make sure they
are checked and clamped.
Change-Id: Ife83b7fed0882bba6d1fa559b6e63c054fd5065d
With this fix, the experimental branch now builds and encodes correctly
with the following two configure options respectively:
--enable-experimental --enable-t8x8
--enable-experimental
Change-Id: I3147c33c503fe713a85fd371e4f1a974805778bf
Do mvp clamping in full-pixel precision instead of 1/8-pixel
precision to avoid error caused by right shifting operation.
Also, further fixed the motion vector limit calculation in change:
b748045470
Change-Id: Ied88a4f7ddfb0476eb9f7afc6ceeddbf209fffd7
Motion vector limits are calculated using right shifts, which
could give wrong results for negative numbers. James Berry's
test on one clip showed encoder produced some artifacts. This
change fixed that.
Change-Id: I035fc02280b10455b7f6eb388f7c2e33b796b018
There were many instances in the code of vp8_coef_tokens and
vp8_coef_tokens-1, which was a preprocessor macro despite the naming
convention. Replace these with MAX_ENTROPY_TOKENS and ENTROPY_NODES,
respectively.
Change-Id: I72c4f6c7634c94e1fa066cd511471e5592c748da
