The previous implementation visited each node in the tree multiple times
because it used each symbol's encoding to revisit the branches taken and
increment its count. Instead, we can traverse the tree depth first and
calculate the probabilities and branch counts as we walk back up. The
complexity goes from somewhere between O(nlogn) and O(n^2) (depending on
how balanced the tree is) to O(n).
Only tested one clip (256kbps, CIF), saw 13% decoding perf improvement.
Note that this optimization should port trivially to VP8 as well. In VP8,
the decoder doesn't use this function, but it does routinely show up
on the profile for realtime encoding.
Change-Id: I4f2848e4f41dc9a7694f73f3e75034bce08d1b12
Adds probability updates for extra bits for the nzcs, code for
getting nzc stats, plus some minor cleanups and fixes.
Change-Id: If2814e7f04fb52f5025ad9f400f3e6c50a00b543
Increase the motion search range by 4x. Change MV_CLASS tree of the
entropy coding to allow two additional mv classes to cover the
extended motion vector limit. The codec determines the effective
motion search range conditioned on the actual frame dimension.
It provides coding gains:
stdhd 0.39%
yt 0.56%
hd 0.47%
Major coding performance gains are packed in several sequences with
intense motion activities, e.g., ped_1080p gains 7% at high bit-rates,
and on average 3%.
TODO: Need to further tune the rate control and motion search units.
Change-Id: Ib842540a6796fbee5a797809433ef6a477c6d78d
This also changes the RD search to take account of the correct block
index when searching (this is required for ADST positioning to work
correctly in combination with tx_select).
Change-Id: Ie50d05b3a024a64ecd0b376887aa38ac5f7b6af6
This patch revamps the entropy coding of coefficients to code first
a non-zero count per coded block and correspondingly remove the EOB
token from the token set.
STATUS:
Main encode/decode code achieving encode/decode sync - done.
Forward and backward probability updates to the nzcs - done.
Rd costing updates for nzcs - done.
Note: The dynamic progrmaming apporach used in trellis quantization
is not exactly compatible with nzcs. A suboptimal approach has been
used instead where branch costs are updated to account for changes
in the nzcs.
TODO:
Training the default probs/counts for nzcs
Change-Id: I951bc1e22f47885077a7453a09b0493daa77883d
Added a variant of the one shot maxQ flag
for two pass that forces a fixed Q for the
normal inter frames. Disabled by default.
Also small adjustment to the Bits per MB
estimation.
Change-Id: I87efdfb2d094fe1340ca9ddae37470d7b278c8b8
A 'superframe' is a group of frames that share the same PTS, but have a
defined decoding order. This commit adds the ability to append an index
to such a group of frames, allowing for random access to the constituent
frames. This could be useful for frame-level parallelism or partial
decoding in a multilayer scenario.
Decoding the stream serially without such an index should work as a
fallback, and VP9/TestSuperframeIndexIsOptional verifies that.
Change-Id: Idff83b7560e1a7077d8fb067bfbc45b567e78b1c
Split macroblock and superblock tokenization and detokenization
functions and coefficient-related data structs so that the bitstream
layout and related code of superblock coefficients looks less like it's
a hack to fit macroblocks in superblocks.
In addition, unify chroma transform size selection from luma transform
size (i.e. always use the same size, as long as it fits the predictor);
in practice, this means 32x32 and 64x64 superblocks using the 16x16 luma
transform will now use the 16x16 (instead of the 8x8) chroma transform,
and 64x64 superblocks using the 32x32 luma transform will now use the
32x32 (instead of the 16x16) chroma transform.
Lastly, add a trellis optimize function for 32x32 transform blocks.
HD gains about 0.3%, STDHD about 0.15% and derf about 0.1%. There's
a few negative points here and there that I might want to analyze
a little closer.
Change-Id: Ibad7c3ddfe1acfc52771dfc27c03e9783e054430
Fixed a couple of variable/function definitions, as well as header
handling to support 16K sequence coding at high bit-rates.
The width and height are each specified by two bytes in the header.
Use an extra byte to explicitly indicate the scaling factors in
both directions, each ranging from 0 to 15.
Tested coding up to 16400x16400 dimension.
Change-Id: Ibc2225c6036620270f2c0cf5172d1760aaec10ec
The width and height stored in the reference frames are padded out to
a multiple of 16. The Width and Height variables in common are the
displayed size, which may be smaller. The incorrect comparison was
causing scaling related code to be called when it shouldn't have
been. A notable case where this happens is 1080p, since 1088 != 1080.
Change-Id: I55f743eeeeaefbf2e777e193bc9a77ff726e16b5
sse4_1 code used uint16_t for returning sad, but that
won't work for 32x32 or 64x64. This code fixes the
assembly for those and also reenables sse4_1 on linux
Change-Id: I5ce7288d581db870a148e5f7c5092826f59edd81
Fixing code style, using array lookup instead of switch statements for
forward hybrid transforms (in the same way as for their inverses).
Consistent usage of ROUND_POWER_OF_TWO macro in appropriate places.
Change-Id: I0d3822ae11f928905fdbfbe4158f91d97c71015f
This function was part of an optimization used in VP8 that required
caching two macroblocks. This is unused in VP9, and might not
survive refactoring to support superblocks, so removing it for now.
Change-Id: I744e585206ccc1ef9a402665c33863fc9fb46f0d
This patch makes the encoder's use of ref_frame_map and active_ref_idx
consistent with the decoder. ref_frame_map[] maps a reference buffer
index to its actual location in the yv12_fb array, since many
references may share an underlying buffer. active_ref_idx[] mirrors
cpi->{lst,gld,alt}_fb_idx, holding the active references in each
slot.
This also fixes a bug in setup_buffer_inter() where the incorrect
reference was used to populate the scaling factors.
Change-Id: Id3728f6d77cffcd27c248903bf51f9c3e594287e
Fixes a bug in vp9_set_internal_size() that prevented returning to
the unscaled state. Updated the ResizeInternalTest to scale both
down and up. Added a check that all frames are within 2.5% of the
quality of the initial keyframe.
Change-Id: I3b7ef17cdac144ed05b9148dce6badfa75cff5c8
This patch extends the previous support for using references of a
different resolution in ZEROMV mode to all inter prediction modes.
Subpixel based best-mv scoring is disabled when the reference frame
differs in resolution from the current frame.
Change-Id: Id4dc3e5e6692de98d9857fd56bfad3ac57e944ac
