1. 11 Mar, 2013 1 commit
  2. 10 Mar, 2013 1 commit
    • John Koleszar's avatar
      Optimize vp9_tree_probs_from_distribution · bd84685f
      John Koleszar authored
      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
      bd84685f
  3. 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
  4. 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
  5. 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
  6. 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
  7. 15 Feb, 2013 1 commit
  8. 14 Feb, 2013 1 commit
  9. 13 Feb, 2013 4 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
    • Paul Wilkins's avatar
      Removal of Hybrid DWT/DCT experiment. · 649be94c
      Paul Wilkins authored
      Removal of experiment to simplify code base for other
      changes.
      
      Change-Id: If0a33952504558511926ad212bc311fc2bffb19a
      649be94c
  10. 13 Jan, 2013 1 commit
    • Deb Mukherjee's avatar
      Further enhancements/fixes on dct/dwt hybrid txfm · 516db21c
      Deb Mukherjee authored
      Fixes some scaling issues. Adds an option to only compute the
      dct on the low-low subband for 32x32 and 64x64 blocks using
      only a single 16x16 dct after 1 and 2 wavelet decomposition
      levels respectively. Also adds an option to use a 8x8 dct
      as building block.
      
      Currenlty with the 2/6 filter and with a single 16x16 dct on
      the low low band, the reuslts compared to full 32x32 dct is
      as follows:
      derf: -0.15%
      yt: -0.29%
      std-hd: -0.18%
      hd: -0.6%
      These are my current recommended settings, since the 2/6 filter
      is very simple.
      
      Results with 8x8 dct are about 0.3% worse.
      
      Change-Id: I00100cdc96e32deced591985785ef0d06f325e44
      516db21c
  11. 10 Jan, 2013 1 commit
  12. 08 Jan, 2013 2 commits
    • Deb Mukherjee's avatar
      Adds 64x64 hybrid dct/dwt transform · 4b7304ee
      Deb Mukherjee authored
      This is to add to the 64x64 transform experiment as an alternative to
      a 64x64 DCT.
      Two levels of wavelet decomposition is used on a 64x64 block, followed
      by 16x16 DCT on the four lowest subbands. The highest three subbands
      are left untransformed after the first level DWT.
      
      Change-Id: I3d48d5800468d655191933894df6b46e15adca56
      4b7304ee
    • Ronald S. Bultje's avatar
      Merge superblocks (32x32) experiment. · 4455036c
      Ronald S. Bultje authored
      Change-Id: I0df99742029834a85c4933652b0587cf5b6b2587
      4455036c
  13. 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
  14. 18 Dec, 2012 3 commits
  15. 13 Dec, 2012 1 commit
    • Deb Mukherjee's avatar
      Further improvements on the hybrid dwt/dct expt · 210dc5b2
      Deb Mukherjee authored
      Modifies the scanning pattern and uses a floating point 16x16
      dct implementation for now to handle scaling better.
      Also experiments are in progress with 2/6 and 9/7 wavelets.
      
      Results have improved to within ~0.25% of 32x32 dct for std-hd
      and about 0.03% for derf. This difference can probably be bridged by
      re-optimizing the entropy stats for these transforms. Currently
      the stats used are common between 32x32 dct and dwt/dct.
      
      Experiments are in progress with various scan pattern - wavelet
      combinations.
      
      Ideally the subbands should be tokenized separately, and an
      experiment will be condcuted next on that.
      
      Change-Id: Ia9cbfc2d63cb7a47e562b2cd9341caf962bcc110
      210dc5b2
  16. 12 Dec, 2012 1 commit
    • Ronald S. Bultje's avatar
      Consistently use get_prob(), clip_prob() and newly added clip_pixel(). · 4d0ec7aa
      Ronald S. Bultje authored
      Add a function clip_pixel() to clip a pixel value to the [0,255] range
      of allowed values, and use this where-ever appropriate (e.g. prediction,
      reconstruction). Likewise, consistently use the recently added function
      clip_prob(), which calculates a binary probability in the [1,255] range.
      If possible, try to use get_prob() or its sister get_binary_prob() to
      calculate binary probabilities, for consistency.
      
      Since in some places, this means that binary probability calculations
      are changed (we use {255,256}*count0/(total) in a range of places,
      and all of these are now changed to use 256*count0+(total>>1)/total),
      this changes the encoding result, so this patch warrants some extensive
      testing.
      
      Change-Id: Ibeeff8d886496839b8e0c0ace9ccc552351f7628
      4d0ec7aa
  17. 08 Dec, 2012 1 commit
    • 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
  18. 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
  19. 28 Nov, 2012 1 commit
  20. 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
  21. 01 Nov, 2012 2 commits
  22. 31 Oct, 2012 3 commits
  23. 22 Oct, 2012 1 commit
  24. 11 Oct, 2012 1 commit
  25. 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
  26. 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
  27. 03 Aug, 2012 1 commit
    • 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
  28. 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
  29. 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
  30. 17 Jul, 2012 1 commit