1. 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
  2. 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
  3. 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
  4. 26 Jul, 2012 1 commit
  5. 23 Jul, 2012 1 commit
  6. 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
  7. 18 Jul, 2012 2 commits
    • Yaowu Xu's avatar
      removed floating point version 8x8 fdct · d632bf8c
      Yaowu Xu authored
      the integer version has very good precision, the float version is no
      longer useful. this commit also removes the experiment option from
      configure script.
      
      Change-Id: Ibb92e63c9f5083357cdf89c559d584a7deb3353f
      d632bf8c
    • Yaowu Xu's avatar
      cleanup experiments in configure · 11e23e67
      Yaowu Xu authored
      this commit removes a number of experiment options from configure
      script. the associated experiments are already fully merged, the
      options in configure script have no effect at all.
      
      Change-Id: I8054ccaee0a04610162ed76ac9e59c4538217113
      11e23e67
  8. 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
  9. 27 Jun, 2012 1 commit
    • Adrian Grange's avatar
      Added Prediction Filter to Mode Selection · bbc926dc
      Adrian Grange authored
      Added the ability to optionally filter the prediction data
      when inter modes are selected (excludes SPLITMV, for now).
      
      The mode selection loop considers both the filtered and
      non-filtered prediction data when choosing mode. The filter
      can be turned on/off at the frame-level, or signaled for
      each MB.
      
      Change-Id: I1b783c71d95a361ab36c761b07e8a6b06bc36822
      bbc926dc
  10. 18 Jun, 2012 1 commit
  11. 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
  12. 15 May, 2012 2 commits
    • Deb Mukherjee's avatar
      Adds new Directional Intra prediction modes. · c5ddb7f0
      Deb Mukherjee authored
      Adds 6 directional intra predictiom modes for 16x16 and 8x8 blocks.
      
      Change-Id: I25eccc0836f28d8d74922e4e9231568a648b47d1
      c5ddb7f0
    • Yaowu Xu's avatar
      Changed to use integer 8x8 dct · b22cc559
      Yaowu Xu authored
      The commit added an integer version of 8x8 forward DCT, based on the
      orginal forward DCT from VP6. The constants, roundings, and shifts
      were adjusted to improve the accuracy. The latest patch has a very
      similar accuracy in term of round trip error against the floating
      point version.
      
      It should be noted here that the purpose of the patch is to help
      encoding speed and facilitate all other experiments. There will be
      futher review in combination with inverse DCT before finalization.
      
      configure with "--enable--int_8x8fdct" to use the integer version
      
      Change-Id: I5a4f80507429f0e07cf02a13768ec81cbfddc5bc
      b22cc559
  13. 11 May, 2012 2 commits
  14. 04 May, 2012 1 commit
  15. 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
  16. 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
  17. 21 Mar, 2012 1 commit
  18. 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
  19. 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
  20. 29 Feb, 2012 1 commit
  21. 28 Feb, 2012 1 commit
    • Paul Wilkins's avatar
      Merge new loop filter. · 19b9d28f
      Paul Wilkins authored
      Merge of the NEWLPF configuration experiment so it is always on.
      
      Change-Id: I7054772b6eab28bad1ff807bfa54d98f83de9308
      19b9d28f
  22. 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
  23. 15 Feb, 2012 2 commits
    • Paul Wilkins's avatar
      Experimental code base simplification. · 46f9ad2c
      Paul Wilkins authored
      Remove error concealment code.
      
      Change-Id: I882705174fbfea212e96f7f684e47a671dbe5c67
      46f9ad2c
    • Yaowu Xu's avatar
      moved segment based LPF level selection under CONFIG_FEATUREUPDATES · d327dcf3
      Yaowu Xu authored
      This commit moved segment based loop filter level selection into
      the experiment of CONFIG_FEATUREUPDATES. As previous commit noted,
      the segment based loop filter selection helps the compression by
      ~0.1% on cif set, the ongoing experiment CONFIG_FEATUREUPDATES
      made encoding updates of the segment based LPF level more efficient,
      hence, another .04% gain on cif set. The commit also fixed an issue
      previously where encoder/decoder may use different loop filter level
      for one of the segments.
      
      Change-Id: Ia978b14aae95bb107d561ba53a7a2bb6ff01faf3
      d327dcf3
  24. 14 Feb, 2012 1 commit
  25. 13 Feb, 2012 1 commit
    • Jim Bankoski's avatar
      vp8 - config_featureupdates · af8f1928
      Jim Bankoski authored
      Added a bit to signify that the feature changed since
      the last time we sent it, or not so that we don't need
      to send all the databits for every feature change.
      
      added config
      
      Change-Id: I8d3064ce90d4500bf0d5c6b87c664e46138dfcac
      af8f1928
  26. 10 Feb, 2012 2 commits
  27. 02 Feb, 2012 1 commit
    • Adrian Grange's avatar
      Added encoding in Superblock Order · 5d0b5a17
      Adrian Grange authored
      As a precursor to encoding 32x32 blocks this cl adds the
      ability to encode the frame superblock (=32x32 block) at
      a time. Within a SB the 4 indiviual MBs are encoded in
      raster-order (NW,NE,SW,SE).
      
      This functionality is added as an experiment which can be
      enabled by ispecifying --enable-superblocks in the
      command line specified to configure (CONFIG_SUPERBLOCKS
      macro in the code).
      
      To make this work I had to disable the two intra
      prediction modes that use data from the top-right of the
      MB.
      
      On the tests that I have run the results produce
      almost exactly the same PSNRs & SSIMs with a very
      slightly higher average data rate (and slightly higher
      data rate than just disabling the two intra modes in
      the original code).
      
      NOTE: This will also break the multi-threaded code.
      
      This replaces the abandoned change:
      Iebebe0d1a50ce8c15c79862c537b765a2f67e162
      
      Change-Id: I1bc1a00f236abc1a373c7210d756e25f970fcad8
      5d0b5a17
  28. 31 Jan, 2012 1 commit
    • Paul Wilkins's avatar
      Added common prediction modules. · b2f64dff
      Paul Wilkins authored
      This function adds the common prediction modules,  some data structures
      and a config option but does not use them.
      
      It also corrects a bug in clearing down  the MODE_INFO border and introduces
      a new element that indicates if an entry corresponds to an "in image" macro block
      or is part of the border.
      
      Change-Id: Ib69eec0876173ebe9d1de9df9537d0b2447702e0
      b2f64dff
  29. 26 Jan, 2012 1 commit
  30. 18 Jan, 2012 1 commit
    • Yaowu Xu's avatar
      new loop filter functions for macroblock boundaries · 5e7d7d3d
      Yaowu Xu authored
      The commit adds a new set of loop filter for macroblock edge filtering.
      The new loop filter has a mask to detect so-called "flat" regions. The
      detection checks 5 pixels of each side of an edge. If the all pixels
      have value with +/-1 from the edge pixel on the same side, the region
      is treated as a "flat" region. For such case, a 7 tap filter is used
      to change 3 pixel values on each side. The 7 taps are:
                     [1, 1, 1, 2, 1, 1, 1]/8
      The furthest away pixels used as input are +/-5 away from edge. For
      non-flat region, we fall back to old filtering. It should be noted
      here that the thresholds and filter taps may require more optimization
      for best possible results.
      
      Tests on a set of hd clips showed consistent gains:
      http://www.corp.google.com/~yaowu/no_crawl/mblpf_hd.html
      (avg psnr: .83% glb psnr: .77% ssim: .82%)
      
      Tests on derf set also showed consistent gains:
      http://www.corp.google.com/~yaowu/no_crawl/mblpf_derf.html
      (avg psnr: .24% glb psnr: .22% ssim: .48%)
      
      Change-Id: I0855b1ff48e79e1175c20b81967137e18b2af352
      5e7d7d3d
  31. 07 Dec, 2011 2 commits
    • Yaowu Xu's avatar
      Removed #if CONFIG_MULCONTEXT · b70f23ca
      Yaowu Xu authored
      This commit removed the macro CONFIG_MULCONTEXT, which was used to
      indicate the experiment code for using separate context for altref
      and normal frames. This commit made the change fully merged in.
      
      Change-Id: I525f927f68e2365d37b340ef23b836a136a4f70b
      b70f23ca
    • 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
  32. 06 Dec, 2011 1 commit
    • Ronald S. Bultje's avatar
      Dual 16x16 inter prediction. · 60cb39da
      Ronald S. Bultje authored
      This patch introduces the concept of dual inter16x16 prediction. A
      16x16 inter-predicted macroblock can use 2 references instead of 1,
      where both references use the same mvmode (new, near/est, zero). In the
      case of newmv, this means that two MVs are coded instead of one. The
      frame can be encoded in 3 ways: all MBs single-prediction, all MBs dual
      prediction, or per-MB single/dual prediction selection ("hybrid"), in
      which case a single bit is coded per-MB to indicate whether the MB uses
      single or dual inter prediction.
      
      In the future, we can (maybe?) get further gains by mixing this with
      Adrian's 32x32 work, per-segment dual prediction settings, or adding
      support for dual splitmv/8x8mv inter prediction.
      
      Gain (on derf-set, CQ mode) is ~2.8% (SSIM) or ~3.6% (glb PSNR). Most
      gain is at medium/high bitrates, but there's minor gains at low bitrates
      also. Output was confirmed to match between encoder and decoder.
      
      Note for optimization people: this patch introduces a 2nd version of
      16x16/8x8 sixtap/bilin functions, which does an avg instead of a
      store. They may want to look and make sure this is implemented to
      their satisfaction so we can optimize it best in the future.
      
      Change-ID: I59dc84b07cbb3ccf073ac0f756d03d294cb19281
      60cb39da
  33. 02 Dec, 2011 1 commit
    • Yaowu Xu's avatar
      changed configure script to enable new experimental options · 8a40d2f5
      Yaowu Xu authored
      Added two experimental options to the configure script:
      1. newnear:
         new scheme of doing mv encoding that include a motion vector from
         last frame in nearest and near mv search
      2. mulcontext:
         tracks entropy context separately for regular frames and alt ref
         frames.
      
      Change-Id: If6e0d5d593351707b497a26eb6a763e080f77e6f
      8a40d2f5
  34. 04 Nov, 2011 1 commit
    • Yaowu Xu's avatar
      make uv intra mode coding adaptive to Y mode · 2bbde250
      Yaowu Xu authored
      This commit tries to do UV intra mode coding adaptive to Y intra mode.
      Entropy context is defined as conditional PDF of uv intra mode given
      the Y mode. All constants are normalized with 256 to be fit in 8 bits.
      
      This provides further coding efficiency beyond the quantizer adaptive
      y intra mode coding. Consistent gains were observed on all clips and
      all bit rates for HD all key encoding tests.
      
      To test, configure with
      --enable-experimental --enable-uvintra
      
      Change-Id: I2d78d73f143127f063e19bd0bac3b68c418d756a
      2bbde250