1. 08 Apr, 2013 1 commit
    • Jingning Han's avatar
      Clamp inferred motion vectors only · 12bf0796
      Jingning Han authored
      Clamp only the motion vectors inferred from neighboring reference
      macroblocks. The motion vectors obtained through motion search in
      NEWMV mode are constrained during the search process, which allows
      a relatively larger referencing region than the inferred mvs.
      Hence further clamping the best mv provided by the motion search may
      affect the efficacy of NEWMV mode.
      
      Synchronized the decoding process. The decoded mvs in NEWMV modes
      should be guaranteed to fit in the effective range. Put a mv range
      clamping function there for security purpose.
      
      This improves the coding performance of high motion sequences, e.g.,
      derf set:
      foreman 0.233%
      husky   0.175%
      icd     0.135%
      mother_daughter 0.337%
      pamphlet        0.561%
      
      stdhd set:
      blue_sky 0.408%
      city     0.455%
      also saw sunflower goes down by -0.469%.
      
      Change-Id: I3fcbba669e56dab779857a8126a91b926e899cb5
      12bf0796
  2. 05 Mar, 2013 1 commit
    • Dmitry Kovalev's avatar
      Code cleanup. · 7f99c3c5
      Dmitry Kovalev authored
      Removing redundant 'extern' keywords, fixing formatting and #include order,
      code simplification.
      
      Change-Id: I0e5fdc8009010f3f885f13b5d76859b9da511758
      7f99c3c5
  3. 09 Feb, 2013 1 commit
    • John Koleszar's avatar
      Replace as_mv struct with array · 7ca517f7
      John Koleszar authored
      Replace as_mv.{first, second} with a two element array, so that they
      can easily be processed with an index variable.
      
      Change-Id: I1e429155544d2a94a5b72a5b467c53d8b8728190
      7ca517f7
  4. 05 Feb, 2013 1 commit
    • Ronald S. Bultje's avatar
      [WIP] Add column-based tiling. · 1407bdc2
      Ronald S. Bultje authored
      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
      1407bdc2
  5. 24 Jan, 2013 1 commit
    • Deb Mukherjee's avatar
      Adds an error-resilient mode with test · 01cafaab
      Deb Mukherjee authored
      Adds an error-resilient mode where frames can be continued
      to be decoded even when there are errors (due to network losses)
      on a prior frame. Specifically, backward updates are turned off
      and probabilities of various symbols are reset to defaults at
      the beginning of each frame. Further, the last frame's mvs are
      not used for the mv reference list, and the sorting of the
      initial list based on search on previous frames is turned off
      as well.
      
      Also adds a test where an arbitrary set of frames are skipped
      from decoding to simulate errors. The test verifies (1) that if
      the error frames are droppable - i.e. frame buffer updates have
      been turned off - there are no mismatch errors for the remaining
      frames after the error frames; and (2) if the error-frames are non
      droppable, there are not only no decoding errors but the mismatch
      PSNR between the decoder's version of the post-error frames and the
      encoder's version is at least 20 dB.
      
      Change-Id: Ie6e2bcd436b1e8643270356d3a930e8989ff52a5
      01cafaab
  6. 18 Dec, 2012 1 commit
  7. 10 Dec, 2012 1 commit
    • Paul Wilkins's avatar
      Further changes to mv reference code. · d1244659
      Paul Wilkins authored
      Some further changes and refactoring of mv
      reference code and selection of center point for
      searches. Mainly relates to not passing so many
      different local copies of things around.
      
      Some place holder comments.
      
      Change-Id: I309f10ffe9a9cde7663e7eae19eb594371c8d055
      d1244659
  8. 07 Dec, 2012 1 commit
  9. 30 Nov, 2012 1 commit
  10. 28 Nov, 2012 1 commit
  11. 27 Nov, 2012 1 commit
    • John Koleszar's avatar
      Add vp9_ prefix to all vp9 files · fcccbcbb
      John Koleszar authored
      Support for gyp which doesn't support multiple objects in the same
      static library having the same basename.
      
      Change-Id: Ib947eefbaf68f8b177a796d23f875ccdfa6bc9dc
      fcccbcbb
  12. 16 Nov, 2012 2 commits
    • Paul Wilkins's avatar
      Further experimentation with the mode context · a57dbd95
      Paul Wilkins authored
      Experiments with a larger set of contexts and some
      clean up to replace magic numbers regarding the
      number of contexts.
      
      The starting values and rate of backwards adaption
      are still suspect and based on a small set of tests.
      Added forwards adjustment of probabilities.
      
      The net result of adding the new context and forward
      update is small compared to the old context from the
      legacy find_near function.  (down a little on derf but
      up by a similar amount for HD)
      
      HOWEVER.... with the new context and forward update
      the impact of disabling the reverse update (which may be
      necessary in some use cases to facilitate parallel decoding)
      is hugely reduced.
      
      For the old context without forward update, the impact of
      turning off reverse update (Experiment was with SB off) was
      Derf - 0.9, Yt -1.89, ythd -2.75 and sthd -8.35. The impact was
      mainly at low data rates.
      
      With the new context and forward update enabled the impact
      for all the test sets was no more than 0.5-1% (again most at
      the low end).
      
      Change-Id: Ic751b414c8ce7f7f3ebc6f19a741d774d2b4b556
      a57dbd95
    • Deb Mukherjee's avatar
      Compound inter-intra experiment · 0c917fc9
      Deb Mukherjee authored
      A patch on compound inter-intra prediction.
      
      In compound inter-intra prediction, a new predictor for
      16x16 inter coded MBs are obtained by combining a single
      inter predictor with a 16x16 intra predictor, in a manner
      that the weight varies with distance from the top/left
      boundary. The current search strategy is to combine the best
      inter mode with the best intra mode obtained independently.
      
      Results so far:
      
      derf +0.31%
      yt +0.32%
      std-hd +0.35%
      hd +0.42%
      
      It is conceivable that the results would improve somewhat
      with a more thorough search strategy where all intra modes
      are searched given the best mv, or even a joint search for
      the best mv and the best intra mode.
      
      Change-Id: I7951f1ed0d6eb31ca32ac24d120f1585bcd8d79b
      0c917fc9
  13. 12 Nov, 2012 1 commit
    • Paul Wilkins's avatar
      New inter mode context · 2669f42b
      Paul Wilkins authored
      This change is a fix / extension of the newbestrefmv
      experiment. As such it is presented without IFDEF.
      
      The change creates a new context for coding inter modes
      in vp9_find_mv_refs(). This replaces the context that
      was previously calculated in vp9_find_near_mvs().
      The new context is unoptimized and not necessarily
      any better at this stage (results pending), but eliminates
      the need for a legacy call to vp9_find_near_mvs().
      Based on numbers from Scott, this could help decode
      speed by several %.
      
      In a later patch I will add support for forward update of
      context (assuming this helps) and refine the context as
      necessary.
      
      Change-Id: I1cd991b82c8df86cc02237a34185e6d67510698a
      2669f42b
  14. 07 Nov, 2012 1 commit
  15. 01 Nov, 2012 3 commits
  16. 31 Oct, 2012 3 commits
  17. 21 Oct, 2012 1 commit
  18. 07 Sep, 2012 1 commit
    • Paul Wilkins's avatar
      MV reference changes · 38e1c791
      Paul Wilkins authored
      Extend experiment to use both vectors from MBs
      coded using compound prediction as candidates.
      
      In final sort only consider best 4 candidates
      for now but make sure 0,0 is always one of them.
      
      Other minor changes to new MV reference code.
      Pass in Mv list to vp8_find_best_ref_mvs().
      
      Change-Id: Ib96220c33c6b80bd1d5e0fbe8b68121be7997095
      38e1c791
  19. 17 Aug, 2012 1 commit
  20. 10 Aug, 2012 1 commit
  21. 07 Aug, 2012 1 commit
    • Yaowu Xu's avatar
      a new way of determining reference motion vector · 8b2f57d0
      Yaowu Xu authored
      Using surrounding reconstructed pixels from left and above to select
      best matching mv to use as reference motion vector for mv encoding.
      
      Test results:
             AVGPSNR  GLBPSNR VPXSSIM
      Derf:  1.107%   1.062%  0.992%
      Std-hd:1.209%   1.176%  1.029%
      
      Change-Id: I8f10e09ee6538c05df2fb9f069abcaf1edb3fca6
      8b2f57d0
  22. 17 Jul, 2012 1 commit
  23. 18 Apr, 2012 1 commit
  24. 15 Mar, 2012 1 commit
    • Yaowu Xu's avatar
      WebM Experimental Codec Branch Snapshot · 6035da54
      Yaowu Xu authored
      This is a code snapshot of experimental work currently ongoing for a
      next-generation codec.
      
      The codebase has been cut down considerably from the libvpx baseline.
      For example, we are currently only supporting VBR 2-pass rate control
      and have removed most of the code relating to coding speed, threading,
      error resilience, partitions and various other features.  This is in
      part to make the codebase easier to work on and experiment with, but
      also because we want to have an open discussion about how the bitstream
      will be structured and partitioned and not have that conversation
      constrained by past work.
      
      Our basic working pattern has been to initially encapsulate experiments
      using configure options linked to #IF CONFIG_XXX statements in the
      code. Once experiments have matured and we are reasonably happy that
      they give benefit and can be merged without breaking other experiments,
      we remove the conditional compile statements and merge them in.
      
      Current changes include:
      * Temporal coding experiment for segments (though still only 4 max, it
        will likely be increased).
      * Segment feature experiment - to allow various bits of information to
        be coded at the segment level. Features tested so far include mode
        and reference frame information, limiting end of block offset and
        transform size, alongside Q and loop filter parameters, but this set
        is very fluid.
      * Support for 8x8 transform - 8x8 dct with 2nd order 2x2 haar is used
        in MBs using 16x16 prediction modes within inter frames.
      * Compound prediction (combination of signals from existing predictors
        to create a new predictor).
      * 8 tap interpolation filters and 1/8th pel motion vectors.
      * Loop filter modifications.
      * Various entropy modifications and changes to how entropy contexts and
        updates are handled.
      * Extended quantizer range matched to transform precision improvements.
      
      There are also ongoing further experiments that we hope to merge in the
      near future: For example, coding of motion and other aspects of the
      prediction signal to better support larger image formats, use of larger
      block sizes (e.g. 32x32 and up) and lossless non-transform based coding
      options (especially for key frames). It is our hope that we will be
      able to make regular updates and we will warmly welcome community
      contributions.
      
      Please be warned that, at this stage, the codebase is currently slower
      than VP8 stable branch as most new code has not been optimized, and
      even the 'C' has been deliberately written to be simple and obvious,
      not fast.
      
      The following graphs have the initial test results, numbers in the
      tables measure the compression improvement in terms of percentage. The
      build has  the following optional experiments configured:
      --enable-experimental --enable-enhanced_interp --enable-uvintra
      --enable-high_precision_mv --enable-sixteenth_subpel_uv
      
      CIF Size clips:
      http://getwebm.org/tmp/cif/
      HD size clips:
      http://getwebm.org/tmp/hd/
      (stable_20120309 represents encoding results of WebM master branch
      build as of commit#7a159071)
      
      They were encoded using the following encode parameters:
      --good --cpu-used=0 -t 0 --lag-in-frames=25 --min-q=0 --max-q=63
      --end-usage=0 --auto-alt-ref=1 -p 2 --pass=2 --kf-max-dist=9999
      --kf-min-dist=0 --drop-frame=0 --static-thresh=0 --bias-pct=50
      --minsection-pct=0 --maxsection-pct=800 --sharpness=0
      --arnr-maxframes=7 --arnr-strength=3(for HD,6 for CIF)
      --arnr-type=3
      
      Change-Id: I5c62ed09cfff5815a2bb34e7820d6a810c23183c
      6035da54
  25. 29 Feb, 2012 1 commit
  26. 06 Feb, 2012 1 commit
    • Paul Wilkins's avatar
      Merged NEWNEAR experiment · 9c9300f5
      Paul Wilkins authored
      This commit merges the NEWNEAR experiment such that it
      is effectively always on.
      
      The fact that there were changes in the threading code again
      highlights the need to strip out such features during the
      bitstream development phase as trying to maintain this code
      (especially as it is not being tested) slows the development cycle.
      
      Change-Id: I8b34950a1333231ced9928aa11cd6d6459984b65
      9c9300f5
  27. 26 Jan, 2012 1 commit
    • John Koleszar's avatar
      Correct clamping in use of vp8_find_near_mvs() · 83cef816
      John Koleszar authored
      Commit e06c242b introduced a change to call vp8_find_near_mvs() only
      once instead of once per reference frame by observing that the only
      effect that the frame had was on the bias applied to the motion
      vector. By keeping track of the sign_bias value, the mv to use could
      be flip-flopped by multiplying its components by -1.
      
      This behavior was subtley wrong in the case when clamping was applied
      to the motion vectors found by vp8_find_near_mvs(). A motion vector
      could be in-bounds with one sign bias, but out of bounds after
      inverting the sign, or vice versa. The clamping must match that done
      by the decoder.
      
      This change modifies vp8_find_near_mvs() to remove the clamping from
      that function. The vp8_pick_inter_mode() and vp8_rd_pick_inter_mode()
      functions instead track the correctly clamped values for both bias
      values, switching between them by simple assignment. The common
      clamping and inversion code is in vp8_find_near_mvs_bias()
      
      Change-Id: I17e1a348d1643497eca0be232e2fbe2acf8478e1
      83cef816
  28. 22 Dec, 2011 1 commit
    • John Koleszar's avatar
      Remove unnecessary ternary constructs · 0c2b2c79
      John Koleszar authored
      The code had a number of constructs like (condition)?1:0,
      which is redundant with C's semantics. In the cases where a boolean
      operator was used in the condition, simply remove the ternary part.
      Otherwise adjust the surrounding expression to remove the condition
      (eg, for rounding up. See pickinter.c and rdopt.c)
      
      Change-Id: Icb2372defa3783cf31857d90b2630d06b2c7e1be
      0c2b2c79
  29. 07 Dec, 2011 2 commits
    • Yaowu Xu's avatar
      Removed #if CONFIG_I8X8 · d37cd976
      Yaowu Xu authored
      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
      d37cd976
    • Yaowu Xu's avatar
      made vp8_mode_context adaptive · 76feb965
      Yaowu Xu authored
      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
      76feb965
  30. 02 Dec, 2011 1 commit
    • Yaowu Xu's avatar
      enabled 8x8 intra prediction modes on inter frames · a8fbab86
      Yaowu Xu authored
      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
      a8fbab86
  31. 28 Nov, 2011 1 commit
    • Yaowu Xu's avatar
      changed find_near_mvs search to include a mb from last frame · 643238a3
      Yaowu Xu authored
      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
      643238a3
  32. 26 Oct, 2011 1 commit
    • Scott LaVarnway's avatar
      Improved mv_bias · 21970d1d
      Scott LaVarnway authored
      Small performance gains.
      
      Change-Id: I709b9390a8a27a70f5f23574313b8db85ac7f23d
      21970d1d
  33. 16 Sep, 2011 1 commit
    • Yaowu Xu's avatar
      add 8x8 intra prediction modes · ca6b85aa
      Yaowu Xu authored
      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
      ca6b85aa
  34. 13 Jun, 2011 1 commit
    • Scott LaVarnway's avatar
      Populate bmi for B_PRED only · 223d1b54
      Scott LaVarnway authored
      Small decode performance gain (~1%) on keyframes.  No
      noticeable gains on encode.  Also changed pick_intra4x4mby_modes()
      to read the above and left block modes for keyframes only.
      
      Change-Id: I1f4885252f5b3e9caf04d4e01e643960f910aba5
      223d1b54