With this patch, the ZEROMV mode is overloaded to represent
a single global dominant motion using one of three models:
1. True zero translation motion (as before)
2. A translation motion different from 0
3. A Rotation-zoom affine model where the predictor is warped
The actual model used is indicated at the frame level for
each reference frame.
A metric that computes the ratio of the error with a global
non-zero model to the error for zero motion, is used to
determine on the encoder side whether to use one of the two
non-zero models or not.
Change-Id: I1f3d235b8860e543191237024a89041ff3aad689
This commit makes the bit-stream syntax support fast selective tile
decoding in a large scale tile array. It reduces the computational
complexity of computing the target tile offset in the bit-stream
from quadratic to linear scale, while maintaining relatively small
stack space requirement (in the order of 1024 bytes instead of 1M
bytes). The overhead cost due to tile separation remains identical.
Change-Id: Id60c6915733d33a627f49e167c57d2534e70aa96
If a non-skipped block has all transform blocks with only 0 data, then
decoder infers skip flag. This affects the loopfilter. No real encoder
would do this though, so it is pointless. Also, it causes headaches in
HW implmentations as the loop filter cannot proceed until all TX blocks
in the block have been checked. There could be up to 768 of them in
64x64 4:4:4 with 4x4 transform.
Change-Id: I45a021d1f27ca7feefed2242605777e70ce7cabd
This commit allows the encoder to process tile coding per 64x64
block. The supported upper limit of tile resolution is the minimum
of frame size and 4096 in each dimension. To turn on, set
--experiment --row-tile
and compile.
It overwrite the old --tile-columns and --tile-rows configurations.
These two parameters now tell the encoder the width and height of
tile in the unit of 64x64 block. For example,
--tile-columns=1 --tile-rows=1
will make a tile contains a single 64x64 block.
Change-Id: Id515749a05cfeb9e9d008291b76bdfb720de0948
This commit allows the internal codec handle arbitrary tile size
in the unit of 64x64 pixel blocks.
Change-Id: I3ad24de392064645bebab887c94e1db957794916
Move the 2D tile info arrays as global variables. This resolves
the local function stack overflow issue due to excessively large
tile info variables. This allows the internal operation to support
up to 1024 row and column tiles.
Change-Id: I6644cc929e5d3a778a5c03a712ebfc0b8729f576
This commit allows the codec to use up to row tiles (optionally
in combination with up to 64 column tiles per row tile). The
minimum tile size is set to be 256x256 pixel block.
Change-Id: I811ca93f0c5eba41e190f6c7c0f064d1083f530f
The max and min tile number reference should be used to support
both row and column tiles. This commit renames the previous col
prefix to avoid confusion.
Change-Id: I487bea43701af946b79023597a9a9a0516480380
Runborgs results on derflr show consistent results between NEW_INTER
and the previous combination of NEWMVREF and COMPOUND_MODES.
Change-Id: Ieba239c4faa7f93bc5c05ad656a7a3b818b4fbfc
Fix the row tile boundary detection issues. This allows to use
more resources for parallel encoding/decoding when avaiable.
Change-Id: Ifda9f66d1d7c2567dd4e0a572a99a83f179b55f9
Besides code cleaning, this patch contains 3 fixes:
(1) Fixed the COMPOUND_MODES for the NEW_NEWMV mode;
(2) Fixed the joint search when the NEAR_FORNEWMV mode (in NEWMVREF)
is being evaluated;
(3) Fixed the WEDGE_PARTITION when the NEAR_FORNEWMV mode (in NEWMVREF)
is being evaluated.
(4) Adjusted the entropy probability value for NEAR_FORNEW mode.
On derflr turning on all 14 experiments (except for global-motion), the
average gain w.r.t. PSNR is +0.07%:
Maximum on bridge_far_cif: +1.02%
Minimum on hallmonitor_cif: -0.16%
Change-Id: I4c9c6ee24a981af7e655a629580641d9f9745f91
Use separate token probabilities and counters for non-transform
blocks (pixel domain) . Initial probabilities are trained with screen_content
clips. On screen_content, it improves coding performance by about
2% (from +16.4% to +18.45%).
The initial probabilities are not optimized for natural videos. So it should
not be used for natural videos. Set FOR_SCREEN_CONTENT as 0/1 to specify
whether or not to enable this patch.
Change-Id: Ifa361c94bb62aa4b783cbfa50de08c3fecae0984
Implements a first version of global motion where the
existing ZEROMV mode is converted to a translation only
global motion mode.
A lot of the code for supporting a rotation-zoom affine
model is also incorporated.
WIP.
Change-Id: Ia1288a8dfe82f89484d4e291780288388e56d91b
Do not treat first element (dc) differently.
on screen_content
tx-skip only: +16.4% (was +15.45%)
no significant impact on natrual videos
Change-Id: I79415a9e948ebbb4a69109311c10126d8a0b96ab
Changes include:
* Uses double for RD cost computation to guard against overflow
for large resolution frames.
* Use previous frame's filter level to code the level better.
* Change precision of the filter parameters.
* Allow spatial variance for x and y to be different
Change-Id: I1669f65eb0ab1e8519962954c92d59e04f1277b7
derflr: +0.556% (a little up from before)
Adds an internal buffer in the encoder to store the deblocked
result to help speed up the search for the best bilateral filter.
Very small change in performance but a lot faster:
derflr: +0.518%
Change-Id: I5d37e016088e559c16317789cfb1c2f49334b2b9
+0.3% on 10-bit
+0.3% on 12-bit
With other high bit compatible experiments on 12-bit
+12.44% (+0.17) over 8-bit baseline
Change-Id: I40b4c382fa54ba4640d08d9d01950ea8c1200bc9
Adds a framework to incorporate a parameterized loop
postfilter in the coding loop after the application of the
standard deblocking loop filter.
The first version uses a straight bilateral filter
where the parameters conveyed are just spatial and
intensity gaussian variances.
Results on derflr:
+0.523% (only with this experiment)
+6.714% (with all expts other than intrabc)
Change-Id: I20d47285b4d25b8c6386ff8af2a75ff88ac2b69b
This patch allows the prediction residues of tx-skipped blocks
to use probs that are different from regular transfrom
coefficients for token entropy coding. Prediction residues are
assumed as in band 6.
The initial value of probs is obtained with stats from limited
tests. The statistic model for constrained token nodes has not
been optimized. The probs for token extra bits have not been
optimized. These can be future work.
Certain coding improvment is observed:
derflr with all experiments: +6.26% (+0.10%)
screen_content with palette: +22.48% (+1.28%)
Change-Id: I1c0d78178ee9f3655febb6f30cdaef8ee9f8e3cc
This experiment, referred as NEWMVREF, also merged with NEWMVREF_SUB8X8
and the latter one has been removed. Runborgs results show that:
(1) Turning on this experiment only, compared against the base:
derflf: Average PSNR 0.40%; Overall PSNR 0.40%; SSIM 0.35%
(2) Turning on all the experiments including this feature, compared against
that without this feature, on the highbitdepth case using 12-bit:
derflf: Average PSNR 0.33%; Overall PSNR 0.32%; SSIM 0.30%.
Now for highbitdepth using 12-bit, compared against base:
derflf: Average PSNR 11.12%; Overall PSNR 11.07%; SSIM 20.27%.
Change-Id: Ie61dbfd5a19b8652920d2c602201a25a018a87a6
The basic idea is to use a pixel’s neighboring colors as
context to predict its own color. Up to 4 neighbors are
considered here: left, left-above, above, right-above.
To reduce the number of contexts, the combination of any
4 (or less) colors are mapped to a reduced number of
patterns. For example, 1111, 2222, 3333, … , can be mapped
to the same pattern: AAAA. SImilarly, 1122, 1133, 2233, …,
can be mapped to the pattern AABB. In this way, the total
number of color contexts is reduced to 16.
This almost doubles the gain of palette coding on screen
content videos.
on screen_content
--enable-palette +14.2%
--enable-palette --enable-tx-skip +21.2%
on derflr
--enable-palette +0.12%
with all other experiments +6.16%
Change-Id: I560306dae216f2ac11a9214968c2ad2319fa1718
Also make changes to transmit palette-enabled flag using
neighbor blocks as context.
on screen_content
--enable-palette +7.35%
on derflr
with all other experiments +6.05%
Change-Id: Id6c2f726d21913d54a3f86ecfea474a4044c27f6
on screen_content
--enable-palette +6.74%
on derflr
with all other experiments +6.02%
(--enable-supertx --enable-copy-mode
--enable-ext-tx --enable-filterintra
--enable-tx64x64 --enable-tx-skip
--enable-interintra --enable-wedge-partition
--enable-compound-modes --enable-new-quant
--enable-palette)
Change-Id: Ib85049b4c3fcf52bf95efbc9d6aecf53d53ca1a3
