1. 16 Aug, 2012 1 commit
    • Jingning Han's avatar
      Fixed decoder mismatch issue · 60ed9545
      Jingning Han authored
      Resolved the decoder mismatch issue due to quantization parameter
      threshold for hybrid transform coding. The macroblock dequantizer
      initialization is moved to be performed before coefficient
      detokenization, since the (de)tokenization is now dependent on the
      macroblock level quantization parameter.
      
      Change-Id: I443da4992ebb70ae4114750b2f1363c0c628580e
      60ed9545
  2. 09 Aug, 2012 1 commit
  3. 07 Aug, 2012 2 commits
    • 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
    • Jingning Han's avatar
      Refactoring hybrid transform coding · 66f440f1
      Jingning Han authored
      The forward and inverse hybrid transforms are now performed using
      single function modules, where the dimension is sent as argument.
      
      Added an inline function clip8b to clip the reconstruction pixels
      into range of 0-255.
      
      Change-Id: Id7d870b3e1aefc092721c80c0af6f641eb5f3747
      66f440f1
  4. 06 Aug, 2012 1 commit
    • Christian Duvivier's avatar
      Add x86_64-darwin11-gcc target. · 82edabce
      Christian Duvivier authored
      This allows building on MountainLion as the 10.6 SDK has been
      removed from the latest Xcode version (4.4 4F250). Also fix
      all warnings for that build.
      
      Change-Id: Ib70bca4a25295f13595f0d10ea9f0229631de5a4
      82edabce
  5. 03 Aug, 2012 4 commits
    • Deb Mukherjee's avatar
      Merging in high_precision_mv experiment · 2af5473a
      Deb Mukherjee authored
      Merged in the high_precision_mv experiment to make it easier
      to work on new mv encoding strategies. Also removed
      coef_update_probs3().
      
      Change-Id: I82d3b0bb642419fe05dba82528bc9ba010e90924
      2af5473a
    • Yaowu Xu's avatar
      enable interleaved decoding of mode and mv · 2e73f901
      Yaowu Xu authored
      Previouly, the decoding of mode and motion vector are done a per frame
      basis followed by residue decoding and reconstuction. The commit added
      the option to allow decoder to interleave the decoding of mode and mvs
      with the residue decoding on a per MB basis.
      
      Change-Id: Ia5316f4a7af9ba7f155c92b5a6fc97201b653571
      2e73f901
    • Jingning Han's avatar
      Replacing the 8x8 DCT with 8x8 ADST/DCT for I8x8 · fcbff9ee
      Jingning Han authored
      Fixed the code review comments.
      
      Under the htrans8x8 experiment the 8X8 DCT in the
      I8X8 mode is replaced with a combination of 8X8 ADST and
      DCT.
      
      Overall coding gains with the htrans8x8 experiment are:
      derf:   0.486
      std-hd: 1.040
      hd:     1.063
      yt:     0.506
      
      Note that part of the gain comes from bigger transforms
      (8x8 instead of 4x4) and part comes from replacing the DCT
      wth the ADST.
      
      Change-Id: I92ca6bbfce11b4165d612b81d9adfad4d010c775
      fcbff9ee
    • Daniel Kang's avatar
      16x16 DCT blocks. · fed8a183
      Daniel Kang authored
      Set on all 16x16 intra/inter modes
      
      Features:
      - Butterfly fDCT/iDCT
      - Loop filter does not filter internal edges with 16x16
      - Optimize coefficient function
      - Update coefficient probability function
      - RD
      - Entropy stats
      - 16x16 is a config option
      
      Have not tested with experiments.
      
      hd:     2.60%
      std-hd: 2.43%
      yt:     1.32%
      derf:   0.60%
      
      Change-Id: I96fb090517c30c5da84bad4fae602c3ec0c58b1c
      fed8a183
  6. 02 Aug, 2012 1 commit
    • Jingning Han's avatar
      Use 8x8 DCT transform for I8X8 prediction mode · c7846ebc
      Jingning Han authored
      Apply 2D-DCT transform of dimension 8x8 to encode prediction
      residuals of I8X8 mode.
      Brought back block type 3 probability context model for 8x8 tokens,
      which is used for the coefficients of Y blocks in I8x8 modes. The
      coefficient costs estimate of I8X8 mode in rate-distortion is also
      changed appropriately.
      Performance results:
      derf:   0.246
      yt:     0.114
      std-hd: 0.730
      hd:     0.670
      
      Change-Id: If1d970eeb4e1827c9f0d2c5b27d33089b347ea27
      c7846ebc
  7. 31 Jul, 2012 1 commit
    • Deb Mukherjee's avatar
      Merging and bug-fix in enhanced_interp experiment · 0ebf548c
      Deb Mukherjee authored
      Merged the enhanced_interp experiment.
      Found and fixed a bug in the include files framework, whereby
      certain encoder files were still using the old INTERP_EXTEND
      value of 3 instead of 4. The thresholds for mv range mcomp.c
      need a small adjustment to prevent crashes.
      
      The results are more or less unchanged.
      
      Change-Id: Iac5008390f1efc97ce1102fbb5f8989c847fb579
      0ebf548c
  8. 30 Jul, 2012 1 commit
    • Deb Mukherjee's avatar
      Adds support for switchable interpolation filters. · 52597441
      Deb Mukherjee authored
      Allows for swtiching/setting interpolation filters at the MB
      level. A frame level flag indicates whether to use a specifc
      filter for the entire frame or to signal the interpolation
      filter for each MB. When switchable filters are used, the
      encoder chooses between 8-tap and 8-tap sharp filters. The
      code currently has options to explore other variations as well,
      which will be cleaned up subsequently.
      
      One issue with the framework is that encoding is slow. I
      tried to do some tricks to speed things up but it is still slow.
      Decoding speed should not be affected since the number of
      filter taps remain unchanged.
      
      With the current version, we are up 0.5% on derf on average but
      some videos city/mobile improve by close to 4 and 2% respectively.
      If we did a full-search by turning the SEARCH_BEST_FILTER flag
      on, the results are somewhat better.
      
      The framework can be combined with filtered prediction, and I
      seek feedback regarding that.
      
      Rebased.
      
      Change-Id: I8f632cb2c111e76284140a2bd480945d6d42b77a
      52597441
  9. 27 Jul, 2012 1 commit
    • Deb Mukherjee's avatar
      Merges several experiments · 9984a155
      Deb Mukherjee authored
      The following five experiments are merged:
      
      newentropy
      newupdate
      adaptive_entropy (also includes a couple of parameter changes
                        that improves results a little
                        in common/entropymode.c and encoder/modecosts.c
                        that were not merged from the internal branch)
      newintramodes
      expanded_coef_context
      
      Change-Id: I8a142a831786ee9dc936f22be1d42a8bced7d270
      9984a155
  10. 19 Jul, 2012 1 commit
    • Jingning Han's avatar
      Adds hybrid transform · 9824230f
      Jingning Han authored
      Adds ADST/DCT hybrid transform coding for Intra4x4 mode.
      The ADST is applied to directions in which the boundary
      pixels are used for prediction, while DCT applied to
      directions without corresponding boundary prediction.
      
      Adds enum TX_TYPE in b_mode_infor to indicate the transform
      type used.
      
      Make coding style consistent with google style.
      Fixed the commented issues.
      
      Experimental results in terms of bit-rate reduction:
      derf:   0.731%
      yt:     0.982%
      std-hd: 0.459%
      hd:     0.725%
      
      Will be looking at 8x8 transforms next.
      
      Change-Id: I46dbd7b80dbb3e8856e9c34fbc58cb3764a12fcf
      9824230f
  11. 17 Jul, 2012 1 commit
  12. 16 Jul, 2012 1 commit
  13. 29 Jun, 2012 1 commit
    • Hui Su's avatar
      Add lossless compression mode. · e44ee38a
      Hui Su authored
      This commit adds lossless compression capability to the experimental
      branch. The lossless experiment can be enabled using --enable-lossless
      in configure. When the experiment is enabled, the encoder will use
      lossless compression mode by command line option --lossless, and the
      decoder automatically recognizes a losslessly encoded clip and decodes
      accordingly.
      
      To achieve the lossless coding, this commit has changed the following:
          1. To encode at lossless mode, encoder forces the use of unit
      quantizer, i.e, Q 0, where effective quantization is 1. Encoder also
      disables the usage of 8x8 transform and allows only 4x4 transform;
          2. At Q 0, the first order 4x4  DCT/IDCT have been switched over
      to a pair of forward and inverse Walsh-Hadamard Transform
      (http://goo.gl/EIsfy),  with proper scaling applied to match the range
      of the original 4x4 DCT/IDCT pair;
          3. At Q 0, the second order remains to use the previous
      walsh-hadamard transform pair. However, to maintain the reversibility
      in second order transform at Q 0, scaling down is applied to first
      order DC coefficients prior to forward transform, and scaling up is
      applied to the second order output prior to quantization. Symmetric
      upscaling and downscaling are added around inverse second order
      transform;
          4. At lossless mode, encoder also disables a number of minor
      features to ensure no loss is introduced, these features includes:
              a. Trellis quantization optimization
              b. Loop filtering
              c. Aggressive zero-binning, rounding and zero-bin boosting
              d. Mode based zero-bin boosting
      
      Lossless coding test was performed on all clips within the derf set,
      to verify that the commit has achieved lossless compression for all
      clips. The average compression ratio is around 2.57 to 1.
      (http://goo.gl/dEShs)
      
      Change-Id: Ia3aba7dd09df40dd590f93b9aba134defbc64e34
      e44ee38a
  14. 26 Jun, 2012 1 commit
    • Deb Mukherjee's avatar
      Continued adaptive entropy coding · f3dff402
      Deb Mukherjee authored
      Incorporates mv_ref, mbsplit and second_mv into the adaptive
      entropy framework. The mv_ref framework has been modified from
      before.
      
      Adds some clean-ups and fixes.
      
      Results with the adaptive entropy experiment are currently up by
      +1.93% on derf; +2.33% std-hd and +1.87% yt-hd.
      
      Fixed a nasty intermittent bug.
      
      Change-Id: I4b1ac9f9483b48432597595195bfec05f31d1e39
      f3dff402
  15. 19 Jun, 2012 1 commit
  16. 15 Jun, 2012 1 commit
    • Deb Mukherjee's avatar
      Adaptive entropy coding of coefficients, modes, mv. · 1fe85a35
      Deb Mukherjee authored
      This patch incorporates adaptive entropy coding of coefficient tokens,
      and mode/mv information based on distributions encountered in a frame.
      Specifically, there is an initial forward update to the probabilities
      in the bitstream as before for coding the symbols in the frame, however
      at the end of decoding each frame, the forward update to the
      probabilities is reverted and instead the probabilities are updated
      towards the actual distributions encountered within the frame.
      The amount of update is weighted by the number of hits within each
      context.
      
      Results on derf/hd/std-hd are all up by 1.6%.
      
      On derf, the most of the gains come from coefficients, however for the
      hd and std-hd sets, the most of the gains come from the mode/mv
      information updates.
      
      Change-Id: I708c0e11fdacafee04940fe7ae159ba6844005fd
      1fe85a35
  17. 12 Jun, 2012 1 commit
    • Yaowu Xu's avatar
      changed to use a fixed number for update probabity · 074a38b1
      Yaowu Xu authored
      This commit is to remove two arrays, which contain the probabilities
      of how likely each probability in coef_probs table is updated. The
      commit changed to use a fixed number "252".
      
      Surprisedly, the overall impact on quality is close to zero, which
      basically says the two big static arrays are not helpful at all.
      derf: -0.016%, -0.020%
      std-hd: 0.000%, -0.013%
      yt: -0.022%, +0.007%
      yt-hd: -0.038%, +0.034%
      
      Change-Id: Ifee94d28a37dcab4f1d2b994bd5b07575be42b72
      074a38b1
  18. 09 May, 2012 1 commit
  19. 08 May, 2012 1 commit
    • Yaowu Xu's avatar
      a number of fixes to entropy stats collection · 54cf1d9a
      Yaowu Xu authored
      1. block types
      There are only three types of blocks for 8x8 transformed MBs, i.e. Y
      block with DC does not exist for 8x8 transformed MBs as all MB using
      8x8 transform have 2nd order haar transform. This commit introduced
      a new macro BLOCK_TYPES_8X8 to reflect such fact.
      
      2. context counters
      This commit also fixed the mixed of context_counters between 4x4 and
      8x8 transformed MBs. The mixed use of the counters leads me to think
      the existing the context probabilities were not properly generated
      from 8x8 transformed MBs.
      
      3. redundant collecting in recoding
      The commit also corrected the code that accumulates entropy stats by
      making sure stats only collected for final packing, not during the
      recode loop
      
      Change-Id: I029f09f8f60bd0c3240cc392ff5c6d05435e322c
      54cf1d9a
  20. 04 May, 2012 1 commit
  21. 26 Apr, 2012 1 commit
    • Deb Mukherjee's avatar
      Adds search option for best interpolation filter. · acdda50a
      Deb Mukherjee authored
      Adds a speed feature to conduct a brute force search among a set of
      available interpolation filters for the best one in an RD sense.
      
      There is a gain of 0.4% on derf, 1.0% on Std-HD.
      
      Patch 2: A macro added to determine if the encoder state is reset
      for each new filter tried.
      
      Patch 3: rebase, also fixes a bug (decodframe.c) introduced by a
      couple of missing function pointer assignements.
      
      Patch 4: rebase.
      
      Change-Id: Ic9ccca9d8c35c6af557449ae867391a2f996cc29
      acdda50a
  22. 24 Apr, 2012 1 commit
    • Deb Mukherjee's avatar
      Differential encoding of probability updates · c6f1bf43
      Deb Mukherjee authored
      Adds differential encoding of prob updates using a subexponential
      code centered around the previous probability value.
      Also searches for the most cost-effective update, and breaks
      up the coefficient updates into smaller groups.
      
      Small gain on Derf: 0.2%
      
      Change-Id: Ie0071e3dc113e3d0d7ab95b6442bb07a89970030
      c6f1bf43
  23. 19 Apr, 2012 1 commit
  24. 18 Apr, 2012 1 commit
  25. 11 Apr, 2012 1 commit
    • Adrian Grange's avatar
      Superblock encoding order · 9daf3154
      Adrian Grange authored
      This is the first patch to add superblock (32x32) coding
      order capabilities. It does not yet do any mode selection
      at the SB level, that will follow in a further patch.
      
      This patch encodes rows of SBs rather than
      MBs, each SB contains 2x2 MBs.
      
      Two intra prediction modes have been disabled since they
      require reconstructed data for the above-right MB which
      may not have been encoded yet (e.g. for the bottom right
      MB in each SB).
      
      Results on the one test clip I have tried (720p GIPS clip)
      suggest that it is somewhere around 0.2dB worse than the
      baseline version, so there may be bugs.
      
      It has been tested with no experiments enabled and with
      the following 3 experiments enabled:
        --enable-enhanced_interp
        --enable-high_precision_mv
        --enable-sixteenth_subpel_uv
      in each case the decode buffer matches the recon buffer
      (using "cmp" to compare the dumped/decoded frames).
      Note: Testing these experiments individually created
      errors.
      
      Some problems were found with other experiments but it
      is unclear what state these experiments are in:
        --enable-comp_intra_pred
        --enable-newentropy
        --enable-uvintra
      
      This code has not been extensively tested yet, so there
      is every likelihood that further bugs remain. I also
      intend to do some code cleanup & refactoring in tandem
      with the next patch that adds the 32x32 modes.
      
      Change-Id: I1eba7f740a70b3510df58db53464535ef881b4d9
      9daf3154
  26. 21 Mar, 2012 2 commits
    • Yaowu Xu's avatar
      enable 8x8 transform for MBs in intra frames · 2823173e
      Yaowu Xu authored
      When ac_yquant>171, a key frame is enabled to use 8x8 transform. In
      such case, MBs with DC_PRED or TM_PRED are selected to use T8x8. This
      change helped the full STD-HD set by ~.1% or so, which is reasonable
      considering how often key frame occurs in these encodings.
      
      Change-Id: Id17009ef6327252177b19e6bf0d6628827febaf1
      2823173e
    • Deb Mukherjee's avatar
      Making subpel filters switchable at frame level · 475d5d56
      Deb Mukherjee authored
      Various refactoring to make the subpel motion compensation
      filters switchable by a frame level field.
      Two types of 8-tap filters are supported in addition to the existing
      bilinar and sixtap filters. One is the default 8-tap and the
      other has a sharper cut-off for use with frames with substantial
      edge content.
      
      Patch 2: Added a preliminary strategy for filter selection based on
      edginess detecton. Also includes some filter changes.
      
      Change-Id: I866085bda5ae143cfdf2ec88157feaabdf7bd63a
      475d5d56
  27. 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
  28. 07 Mar, 2012 1 commit
    • Paul Wilkins's avatar
      Snapshot candidate · 68033ca4
      Paul Wilkins authored
      Pulled out super block code for the snapshot as this
      is not quite ready and will need an extensive re-merge.
      
      Change-Id: I436369b511257447a7b0ea064016cb63f5011849
      68033ca4
  29. 01 Mar, 2012 1 commit
  30. 29 Feb, 2012 1 commit
  31. 28 Feb, 2012 3 commits
    • Deb Mukherjee's avatar
      Initial refactoring of high_precision mv code. · 3e1cad9c
      Deb Mukherjee authored
      This is the first patch for refactoring of the code related to
      high-precision mv, so that 1/4 and 1/8 pel motion vectors can
      co-exist in the same bit-stream by use of a frame level flag.
      The current patch works fine for only use of 1/4th and
      only use of 1/8th pel mv, but there are some issues with the
      mode switching in between. Subsequent patches on this change Id
      will fix the remaining issues.
      
      Patch 2: Adds fixes to make sure that multiple mv precisions can
      co-exist in the bit-stream. Frame level switching has been tested
      to work correctly.
      
      Patch 3: Fixes lines exceeding 80 char
      
      Patch 4:
      http://www.corp.google.com/~debargha/vp8_results/enhinterp.html
      
      Results on derf after ssse3 bugfix, compared to everything
      enabled but the 8-tap, 1/8-subpel and 1/16-subpel uv. Overall the
      gains are about 3% now. Hopefully there are no more bugs lingering.
      Apparently the sse3 bug affected the quartel subpel results more than
      the eighth pel ones (which is understandabale because one bad predictor
      due to the bug, matters less if there are a lot more subpel options
      available as in the 1/8 subpel case).
      The results in the 4th column correspond to the current settings.
      The first two columns correspond to two settings of adaptive switching
      of the 1/4 or 1/8 subpel mode based on initial Q estimate. These
      do not work as good as just using 1/8 all the time yet.
      
      Change-Id: I3ef392ad338329f4d68a85257a49f2b14f3af472
      3e1cad9c
    • Paul Wilkins's avatar
      Experimental branch code clean up. · 25c127f5
      Paul Wilkins authored
      Removal of some further code relating to partitions
      and error resilience.
      
      Spelling correction.
      
      Change-Id: I36067aae67a4a23bec359541dda3400b0bbf26d0
      25c127f5
    • Paul Wilkins's avatar
      Code Simplification · b6f02c85
      Paul Wilkins authored
      Removal of code relating to token partitioning
      
      Change-Id: Iaf3c88d6758639a55bd92c3be5c51e6bed407a3c
      b6f02c85
  32. 27 Feb, 2012 1 commit
    • Paul Wilkins's avatar
      Corrected spelling · b00ed02a
      Paul Wilkins authored
      Apparently the correct spelling of segement is segment !
      
      Change-Id: I88593ee0523f251b3a96794c6166ef8c7898a029
      b00ed02a
  33. 23 Feb, 2012 1 commit
    • Deb Mukherjee's avatar
      Supporting high precision 1/8-pel motion vectors · 18e90d74
      Deb Mukherjee authored
      This is the initial patch for supporting 1/8th pel
      motion. Currently if we configure with enable-high-precision-mv,
      all motion vectors would default to 1/8 pel. Encode and
      decode syncs fine with the current code. In the next phase
      the code will be refactored so that we can choose the 1/8
      pel mode adaptively at a frame/segment/mb level.
      
      Derf results:
      http://www.corp.google.com/~debargha/vp8_results/enhinterp_hpmv.html
      (about 0.83% better than 8-tap interpoaltion)
      
      Patch 3: Rebased. Also adding 1/16th pel interpolation for U and V
      
      Patch 4: HD results.
      http://www.corp.google.com/~debargha/vp8_results/enhinterp_hd_hpmv.html
      Seems impressive (unless I am doing something wrong).
      
      Patch 5: Added mmx/sse for bilateral filtering, as well as enforced
      use of c-versions of subpel filters with 8-taps and 1/16th pel;
      Also redesigned the 8-tap filters to reduce the cut-off in order to
      introduce a denoising effect. There is a new configure option
      sixteenth-subpel-uv which will use 1/16 th pel interpolation for
      uv, if the motion vectors have 1/8 pel accuracy.
      
      With the fixes the results are promising on the derf set. The enhanced
      interpolation option with 8-taps alone gives 3% improvement over thei
      derf set:
      http://www.corp.google.com/~debargha/vp8_results/enhinterpn.html
      
      Results on high precision mv and on the hd set are to follow.
      
      Patch 6: Adding a missing condition for CONFIG_SIXTEENTH_SUBPEL_UV in
      vp8/common/x86/x86_systemdependent.c
      
      Patch 7: Cleaning up various debug messages.
      
      Patch 8: Merge conflict
      
      Change-Id: I5b1d844457aefd7414a9e4e0e06c6ed38fd8cc04
      18e90d74