1. 07 Dec, 2012 1 commit
    • Ronald S. Bultje's avatar
      32x32 transform for superblocks. · c456b35f
      Ronald S. Bultje authored
      This adds Debargha's DCT/DWT hybrid and a regular 32x32 DCT, and adds
      code all over the place to wrap that in the bitstream/encoder/decoder/RD.
      
      Some implementation notes (these probably need careful review):
      - token range is extended by 1 bit, since the value range out of this
        transform is [-16384,16383].
      - the coefficients coming out of the FDCT are manually scaled back by
        1 bit, or else they won't fit in int16_t (they are 17 bits). Because
        of this, the RD error scoring does not right-shift the MSE score by
        two (unlike for 4x4/8x8/16x16).
      - to compensate for this loss in precision, the quantizer is halved
        also. This is currently a little hacky.
      - FDCT and IDCT is double-only right now. Needs a fixed-point impl.
      - There are no default probabilities for the 32x32 transform yet; I'm
        simply using the 16x16 luma ones. A future commit will add newly
        generated probabilities for all transforms.
      - No ADST version. I don't think we'll add one for this level; if an
        ADST is desired, transform-size selection can scale back to 16x16
        or lower, and use an ADST at that level.
      
      Additional notes specific to Debargha's DWT/DCT hybrid:
      - coefficient scale is different for the top/left 16x16 (DCT-over-DWT)
        block than for the rest (DWT pixel differences) of the block. Therefore,
        RD error scoring isn't easily scalable between coefficient and pixel
        domain. Thus, unfortunately, we need to compute the RD distortion in
        the pixel domain until we figure out how to scale these appropriately.
      
      Change-Id: I00386f20f35d7fabb19aba94c8162f8aee64ef2b
      c456b35f
  2. 30 Nov, 2012 1 commit
  3. 28 Nov, 2012 1 commit
  4. 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
  5. 16 Nov, 2012 1 commit
    • 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
  6. 01 Nov, 2012 2 commits
  7. 31 Oct, 2012 3 commits
  8. 22 Oct, 2012 1 commit
  9. 17 Oct, 2012 1 commit
    • John Koleszar's avatar
      Interleave modes/residual per macroblock · 6ef5a005
      John Koleszar authored
      Packs the bitstream with each mb's residual following its mode/mv
      information.
      
      TODO: There are still a few fields that should be packed into partition
      0 but are included in partition 1, due to them being serialized from
      write_kfmodes/pack_inter_mode_mvs, which execute after the first
      partition is finalized. These need to be separated out into a separate
      function, similar to mb_mode_mv_init() in decodemv.c.
      
      Change-Id: I43a46c363601ab36954d07ebe498760e1e2e3af4
      6ef5a005
  10. 11 Oct, 2012 1 commit
  11. 27 Sep, 2012 1 commit
    • Deb Mukherjee's avatar
      Entropy coding for hybrid transform · 3f5d60b3
      Deb Mukherjee authored
      Separates the entropy coding context models for 4x4, 8x8 and 16x16
      ADST variants.
      
      There is a small improvement for HD (hd/std-hd) by about 0.1-0.2%.
      Results on derf/yt are about the same, probably because there is not
      enough statistics.
      
      Results may improve somewhat once the initial probability tables are
      updated for the hybrid transforms which is coming soon.
      
      Change-Id: Ic7c0c62dacc68ef551054fdb575be8b8507d32a8
      3f5d60b3
  12. 21 Sep, 2012 1 commit
    • Deb Mukherjee's avatar
      Separating 8x8DCT use from hybridtransform8x8 · 70e21afb
      Deb Mukherjee authored
      With this change, even if hybridtransform8x8 experiment is off,
      8x8 dct is used for the I8x8 mode. However note that the gains
      observed with the hybridtransform8x8 experiment will now be less,
      since part of the gain is now merged in.
      
      Change-Id: I9afb3880906fd0a1368a374041fc08efcf060c54
      70e21afb
  13. 30 Aug, 2012 1 commit
    • Jingning Han's avatar
      hybrid transform of 16x16 dimension · de6dfa6b
      Jingning Han authored
      Enable ADST/DCT of dimension 16x16 for I16X16 modes. This change provides
      benefits mostly for hd sequences.
      
      Set up the framework for selectable transform dimension.
      
      Also allowing quantization parameter threshold to control the use
      of hybrid transform (This is currently disabled by setting threshold
      always above the quantization parameter. Adaptive thresholding can
      be built upon this, which will further improve the coding performance.)
      
      The coding performance gains (with respect to the codec that has all
      other configuration settings turned on) are
      
      derf:   0.013
      yt:     0.086
      hd:     0.198
      std-hd: 0.501
      
      Change-Id: Ibb4263a61fc74e0b3c345f54d73e8c73552bf926
      de6dfa6b
  14. 03 Aug, 2012 3 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
    • 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
  15. 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
  16. 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
  17. 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
  18. 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
  19. 17 Jul, 2012 1 commit
  20. 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
  21. 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
  22. 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
  23. 09 May, 2012 1 commit
  24. 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
  25. 04 May, 2012 2 commits
  26. 02 May, 2012 1 commit
    • Yaowu Xu's avatar
      slight adjustment to coef band definition · bd69b7d4
      Yaowu Xu authored
      This commit adjusted slightly the 4x4 coefficents band definition to
      better classify coefficients with similar distributions and usages.
      It helps derf set about .1%, it is alos slightly positive for std-hd
      set, where 4x4 blocks are used less frequently.
      
      The commit also removed a const array not in use.
      
      Change-Id: I78d16905d4036641ec905b0c32c190c1def5b249
      bd69b7d4
  27. 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
  28. 17 Apr, 2012 1 commit
    • Attila Nagy's avatar
      Makes all global data in entropy.c const · a91b42f0
      Attila Nagy authored
      Removes all runtime initialization of global data in entropy.c.
      Precalculated values are used for initializing all entropy related
      tabels.
      
      First patch in a series to make sure code is reentrant.
      
      Change-Id: I9aac91a2a26f96d73c6470d772a343df63bfe633
      a91b42f0
  29. 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
  30. 01 Mar, 2012 1 commit
  31. 09 Feb, 2012 1 commit
  32. 03 Nov, 2011 1 commit
    • Paul Wilkins's avatar
      Segment Features. Removal of #ifdefs · a10a268e
      Paul Wilkins authored
      Removal of configure #ifdefs so that segment features
      always available. Removal of code supporting old
      segment feature method.
      
      Still a good deal of tidying up to do.
      
      Change-Id: I397855f086f8c09ab1fae0a5f65d9e06d2e3e39f
      a10a268e
  33. 02 Nov, 2011 1 commit
    • Paul Wilkins's avatar
      Segmentation: Reference frames · 87ff8620
      Paul Wilkins authored
      Modify reference frame segmentation so that ONE or MORE
      reference frames may be marked as a available for a given
      segment.
      
      Fixed bugs relating to segment coding of INTRA and some
      INTER modes at the segment level.
      
      Modified Q boost for static areas based on ambient average Q.
      
      Strong results now on clips with significant static areas.
      (some data points in derf set as high as 9% and some static &
      slide show type content in YT set > 20%)
      
      Change-Id: Ia79f912efa84b977f35a23683ae3643251e24f0c
      87ff8620
  34. 13 Sep, 2011 1 commit
    • Paul Wilkins's avatar
      Segment Features: · dfbc61f3
      Paul Wilkins authored
      Some basic plumbing added for a range of segment level features.
      MB_LVL_* changed to SEG_LVL_* to better reflect meaning.
      
      Change-Id: Iac96da36990aa0e40afc0d86e990df337fd0c50b
      dfbc61f3