1. 26 Apr, 2013 1 commit
  2. 22 Apr, 2013 3 commits
  3. 19 Apr, 2013 1 commit
  4. 11 Apr, 2013 3 commits
  5. 10 Apr, 2013 1 commit
    • Ronald S. Bultje's avatar
      Make SB coding size-independent. · a3874850
      Ronald S. Bultje authored
      Merge sb32x32 and sb64x64 functions; allow for rectangular sizes. Code
      gives identical encoder results before and after. There are a few
      macros for rectangular block sizes under the sbsegment experiment; this
      experiment is not yet functional and should not yet be used.
      
      Change-Id: I71f93b5d2a1596e99a6f01f29c3f0a456694d728
      a3874850
  6. 26 Mar, 2013 4 commits
    • Ronald S. Bultje's avatar
      Add col/row-based coefficient scanning patterns for 1D 8x8/16x16 ADSTs. · d9094d8f
      Ronald S. Bultje authored
      These are mostly just for experimental purposes. I saw small gains (in
      the 0.1% range) when playing with this on derf.
      
      Change-Id: Ib21eed477bbb46bddcd73b21c5c708a5b46abedc
      d9094d8f
    • Ronald S. Bultje's avatar
      Redo banding for all transforms. · 3120dbdd
      Ronald S. Bultje authored
      Now that the first AC coefficient in both directions use the same DC
      as their context, there no longer is a purpose in letting both have
      their own band. Merging these two bands allows us to split bands for
      some of the very high-frequency AC bands.
      
      In addition, I'm redoing the banding for the 1D-ADST col/row scans. I
      don't think the old banding made any sense at all (it merged the last
      coefficient of the first row/col in the same band as the first two of
      the second row/col), which was clearly an oversight from the band being
      applied in scan-order (rather than in their actual position). Now,
      coefficients at the same position will be in the same band, regardless
      what scan order is used. I think this makes most sense for the purpose
      of banding, which is basically "predict energy for this coefficient
      depending on the energy of context coefficients" (i.e. pt).
      
      After full re-training, together with previous patch, derf gains about
      1.2-1.3%, and hd/stdhd gain about 0.9-1.0%.
      
      Change-Id: I7a0cc12ba724e88b278034113cb4adaaebf87e0c
      3120dbdd
    • Ronald S. Bultje's avatar
      Use above/left (instead of previous in scan-order) as token context. · 790fb132
      Ronald S. Bultje authored
      Pearson correlation for above or left is significantly higher than for
      previous-in-scan-order (absolute values depend on position in scan, but
      in general, we gain about 0.1-0.2 by using either above or left; using
      both basically just makes this even better). For eob branch skipping,
      we continue to use the previous token in scan order.
      
      This helps about 0.9% on derf after re-training on a limited data set.
      Full re-training and results on larger-resolution clips are pending.
      
      Note that this commit breaks trellis, so we can probably get further
      gains out of it by fixing trellis at some later point.
      
      Change-Id: Iead68e296fc3a105cca746b5e3da9555d6010cfe
      790fb132
    • Deb Mukherjee's avatar
      Modeling default coef probs with distribution · fd18d5df
      Deb Mukherjee authored
      Replaces the default tables for single coefficient magnitudes with
      those obtained from an appropriate distribution. The EOB node
      is left unchanged. The model is represeted as a 256-size codebook
      where the index corresponds to the probability of the Zero or the
      One node. Two variations are implemented corresponding to whether
      the Zero node or the One-node is used as the peg. The main advantage
      is that the default prob tables will become considerably smaller and
      manageable. Besides there is substantially less risk of over-fitting
      for a training set.
      
      Various distributions are tried and the one that gives the best
      results is the family of Generalized Gaussian distributions with
      shape parameter 0.75. The results are within about 0.2% of fully
      trained tables for the Zero peg variant, and within 0.1% of the
      One peg variant.
      
      The forward updates are optionally (controlled by a macro)
      model-based, i.e. restricted to only convey probabilities from the
      codebook. Backward updates can also be optionally (controlled by
      another macro) model-based, but is turned off by default. Currently
      model-based forward updates work about the same as unconstrained
      updates, but there is a drop in performance with backward-updates
      being model based.
      
      The model based approach also allows the probabilities for the key
      frames to be adjusted from the defaults based on the base_qindex of
      the frame. Currently the adjustment function is a placeholder that
      adjusts the prob of EOB and Zero node from the nominal one at higher
      quality (lower qindex) or lower quality (higher qindex) ends of the
      range. The rest of the probabilities are then derived based on the
      model from the adjusted prob of zero.
      
      Change-Id: Iae050f3cbcc6d8b3f204e8dc395ae47b3b2192c9
      fd18d5df
  7. 12 Mar, 2013 1 commit
  8. 09 Mar, 2013 1 commit
    • Deb Mukherjee's avatar
      Continued experiment with nonzero count · a28139c8
      Deb Mukherjee authored
      Adds probability updates for extra bits for the nzcs, code for
      getting nzc stats, plus some minor cleanups and fixes.
      
      Change-Id: If2814e7f04fb52f5025ad9f400f3e6c50a00b543
      a28139c8
  9. 07 Mar, 2013 1 commit
    • Deb Mukherjee's avatar
      Coding con-zero count rather than EOB for coeffs · eb6ef241
      Deb Mukherjee authored
      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
      eb6ef241
  10. 05 Mar, 2013 1 commit
    • Ronald S. Bultje's avatar
      Make superblocks independent of macroblock code and data. · 111ca421
      Ronald S. Bultje authored
      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
      111ca421
  11. 23 Feb, 2013 2 commits
    • Ronald S. Bultje's avatar
      Split coefficient token tables intra vs. inter. · 0c9e2e9a
      Ronald S. Bultje authored
      Change-Id: I5416455f8f129ca0f450d00e48358d2012605072
      0c9e2e9a
    • Paul Wilkins's avatar
      Further changes to coefficient contexts. · c17672a3
      Paul Wilkins authored
      This patch alters the balance of context between the
      coefficient bands (reflecting the position of coefficients
      within a transform blocks) and the energy of the previous
      token (or tokens) within a block.
      
      In this case the number of coefficient bands is reduced
      but more previous token energy bands are supported.
      
      Some initial rebalancing of the default tables has been
      by running multiple derf clips at multiple data rates using
      the ENTOPY_STATS macro. Further balancing needs to be
      done using larger image formatsd especially in regard to
      the bigger transform sizes which are not as well represented
      in encodings of smaller image formats.
      
      Change-Id: If9736e95c391e711b04aef6393d26f60f36e1f8a
      c17672a3
  12. 15 Feb, 2013 1 commit
  13. 14 Feb, 2013 1 commit
  14. 13 Feb, 2013 3 commits
    • Paul Wilkins's avatar
      Abstract selection of coef band. · 9255ad10
      Paul Wilkins authored
      This patch abstracts the selection of the coefficient band
      context into a function as a precursor to further experiments
      with the coefficient context.
      
      It also removes the large per TX size coefficient band structures
      and uses a single matrix for all block sizes within the test function.
      
      This may have an impact on quality (results to follow) but is only an
      intermediate step in the process of redefining the context. Also the
      quality impact will be larger initially because the default tables will
      be out of step with the new banding.
      
      In particular the 4x4 will in this case only use 7 bands. If needed we
      can add back block size dependency localized within the function, but
      this can follow on after the other changes to the definition of the
      context.
      
      Change-Id: Id7009c2f4f9bb1d02b861af85fd8223d4285bde5
      9255ad10
    • Paul Wilkins's avatar
      Abstract the selection of coefficient context. · 0d284ffe
      Paul Wilkins authored
      This is an initial step to facilitate experimentation
      with changes to the prior token context used to code
      coefficients to take better account of the energy of
      preceding tokens.
      
      This patch merely abstracts the selection of context into
      two functions and does not alter the output.
      
      Change-Id: I117fff0b49c61da83aed641e36620442f86def86
      0d284ffe
    • Paul Wilkins's avatar
      Remove NEWCOEFCONTEXT experiment. · 6a9f0c61
      Paul Wilkins authored
      Removal of the  NEWCOEFCONTEXT experiment to
      reduce code clutter and make it easier to experiment with
      some other changes to the coefficient coding context.
      
      Change-Id: Icd17b421384c354df6117cc714747647c5eb7e98
      6a9f0c61
  15. 10 Jan, 2013 1 commit
  16. 08 Jan, 2013 1 commit
  17. 20 Dec, 2012 1 commit
    • Deb Mukherjee's avatar
      New previous coef context experiment · 08f0c7cc
      Deb Mukherjee authored
      Adds an experiment to derive the previous context of a coefficient
      not just from the previous coefficient in the scan order but from a
      combination of several neighboring coefficients previously encountered
      in scan order.  A precomputed table of neighbors for each location
      for each scan type and block size is used. Currently 5 neighbors are
      used.
      
      Results are about 0.2% positive using a strategy where the max coef
      magnitude from the 5 neigbors is used to derive the context.
      
      Change-Id: Ie708b54d8e1898af742846ce2d1e2b0d89fd4ad5
      08f0c7cc
  18. 18 Dec, 2012 2 commits
  19. 08 Dec, 2012 2 commits
    • Yaowu Xu's avatar
      experiment with CONTEXT conversion · ab480ced
      Yaowu Xu authored
      This commit changed the ENTROPY_CONTEXT conversion between MBs that
      have different transform sizes.
      
      In additioin, this commit also did a number of cleanup/bug fix:
      1. removed duplicate function vp9_fix_contexts() and changed to use
      vp8_reset_mb_token_contexts() for both encoder and decoder
      2. fixed a bug in stuff_mb_16x16 where wrong context was used for
      the UV.
      3. changed reset all context to 0 if a MB is skipped to simplify the
      logic.
      
      Change-Id: I7bc57a5fb6dbf1f85eac1543daaeb3a61633275c
      ab480ced
    • Ronald S. Bultje's avatar
      Introduce vp9_coeff_probs/counts/stats/accum types. · 885cf816
      Ronald S. Bultje authored
      Use these, instead of the 4/5-dimensional arrays, to hold statistics,
      counts, accumulations and probabilities for coefficient tokens. This
      commit also re-allows ENTROPY_STATS to compile.
      
      Change-Id: If441ffac936f52a3af91d8f2922ea8a0ceabdaa5
      885cf816
  20. 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
  21. 30 Nov, 2012 1 commit
  22. 28 Nov, 2012 1 commit
  23. 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
  24. 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
  25. 01 Nov, 2012 2 commits
  26. 31 Oct, 2012 2 commits