This probably has a mildly negative impact on performance, but will
(in future commits - or possibly merged with this one) allow SIMD
implementations of individual intra prediction functions. We may
perhaps want to consider having separate functions per txfm-size
also (i.e. 4x4, 8x8, 16x16 and 32x32 intra prediction functions for
each intra prediction mode), but I haven't played much with that
yet.
Change-Id: Ie739985eee0a3fcbb7aed29ee6910fdb653ea269
This commit enables configurable reference buffer pointer for intra
predictor. This allows later removal of spatial dependency between
blocks inside a 64x64 superblock in the rate-distortion optimization
loop.
Change-Id: I02418c2077efe19adc86e046a6b49364a980f5b1
Removed one 4x4 prediction step that was unnessary in the rd loop.
Removed a unused modecosts estimate from encoder side.
Change-Id: I65221a52719d6876492996955ef04142d2752d86
This commit changed the encoding and decoding of intra blocks to be
based on transform block. In each prediction block, the intra coding
iterates thorough each transform block based on raster scan order.
This commit also fixed a bug in D135 prediction code.
TODO next:
The RD mode/txfm_size selection should take this into account when
computing RD values.
Change-Id: I6d1be2faa4c4948a52e830b6a9a84a6b2b6850f6
Also fixed two minor subtle boundary conditions in intra prediction
code, and replaced memcpy/memset with vpx_ prefixed version.
Change-Id: I9cddff3be831228b628f1f2f065a61feacbcbee6
The commmit changed to use same intra prediction function for all
block sizes.
Some details on the changes:
1. All directional modes except DC/TM/V/H now have built-in filtering
for all pixels with filter taps either (1, 2, 1)/4 or (1, 1)/2.
2. Above edge get automatic extended to double width (bw*2), which
makes a lot of the prediciton mode computation simpler.
3. Same intra prediction function is called with different size
for i4x4_pred and all other larger size.
Overall, the change helped keyframe only coding for both cif size
and std-hd size test sets by .5% consistently on all encodings.
For normal coding with single/auto key frame, the change now also
is consistently net positive for all encodings. The overall gains
is about .15% on std-hd set.
Change-Id: I01ceb31fbc73d49776262e6bdc06853b03bbd1d1
This commit enables rectangular block prediction of compound
inter-intra mode. It combines the mb/sb32/sb64 prediction functions
into a unified version with configurable block width and height.
This fixes the enc/dec mismatch of the codebase when
comp-interintra-pred is enabled.
Change-Id: I1d0db2f1f184007802df04fcd12b9dadb3189ff0
First in a series of commits moving the framebuffers pointers to
per-plane data, so that they can be indexed numerically rather than
by name.
Change-Id: I6e0d60fd4d51e6375c384eb7321776564df21775
Use in-place buffers (dst of MACROBLOCKD) for macroblock prediction.
This makes the macroblock buffer handling consistent with those of
superblock. Remove predictor buffer MACROBLOCKD.
Change-Id: Id1bcd898961097b1e6230c10f0130753a59fc6df
The intra predictor supports configurable block sizes. It can handle
intra prediction down to 4x4 sizes, when enabled in BLOCK_SIZE_TYPE.
Change-Id: I7399ec2512393aa98aadda9813ca0c83e19af854
This patch will use the dest buffer instead of the
predictor buffer. This will allow us in future commits
to remove the extra mem copy that occurs in the dequant
functions when eob == 0. We should also be able to remove
extra params that are passed into the dequant functions.
Change-Id: I7241bc1ab797a430418b1f3a95b5476db7455f6a
- Using multiplication and shifting instead of division in
intra prediction.
- Maximum absolute difference is 1 for division statements
in d45, d27, d63 prediction modes. However, errors can
cumulate for large block sizes when using already predicted
values.
- Maximum number of non-matching result values in loops using
division are:
4x4 0/16
8x8 0/64
16x16 10/256
32x32 13/1024
64x64 122/4096
Overall PSNR
derf: 0.005
yt: -0.022
std-hd: 0.021
hd: -0.006
Change-Id: I3979a02eb6351636442c1af1e23d6c4e6ec1d01d
This patch adds column-based tiling. The idea is to make each tile
independently decodable (after reading the common frame header) and
also independendly encodable (minus within-frame cost adjustments in
the RD loop) to speed-up hardware & software en/decoders if they used
multi-threading. Column-based tiling has the added advantage (over
other tiling methods) that it minimizes realtime use-case latency,
since all threads can start encoding data as soon as the first SB-row
worth of data is available to the encoder.
There is some test code that does random tile ordering in the decoder,
to confirm that each tile is indeed independently decodable from other
tiles in the same frame. At tile edges, all contexts assume default
values (i.e. 0, 0 motion vector, no coefficients, DC intra4x4 mode),
and motion vector search and ordering do not cross tiles in the same
frame.
t log
Tile independence is not maintained between frames ATM, i.e. tile 0 of
frame 1 is free to use motion vectors that point into any tile of frame
0. We support 1 (i.e. no tiling), 2 or 4 column-tiles.
The loopfilter crosses tile boundaries. I discussed this briefly with Aki
and he says that's OK. An in-loop loopfilter would need to do some sync
between tile threads, but that shouldn't be a big issue.
Resuls: with tiling disabled, we go up slightly because of improved edge
use in the intra4x4 prediction. With 2 tiles, we lose about ~1% on derf,
~0.35% on HD and ~0.55% on STD/HD. With 4 tiles, we lose another ~1.5%
on derf ~0.77% on HD and ~0.85% on STD/HD. Most of this loss is
concentrated in the low-bitrate end of clips, and most of it is because
of the loss of edges at tile boundaries and the resulting loss of intra
predictors.
TODO:
- more tiles (perhaps allow row-based tiling also, and max. 8 tiles)?
- maybe optionally (for EC purposes), motion vectors themselves
should not cross tile edges, or we should emulate such borders as
if they were off-frame, to limit error propagation to within one
tile only. This doesn't have to be the default behaviour but could
be an optional bitstream flag.
Change-Id: I5951c3a0742a767b20bc9fb5af685d9892c2c96f
Adds a special combination mode specific to intra prediciton
mode D45.
Current results with the compound inter/intra experiment:
derf: 0.2%
yt: 0.55%
std-hd: 0.75%
hd: 0.74%
Change-Id: I8976bdf3b9b0b66ab8c5c628bbc62c14fc72ca86
Uses a single 1D table to implement the weighting of the predictors
for the compound inter-intra experiment.
Change-Id: I204ffbe4f9fc79d5d43b6c724ad253d800461012