1. 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
  2. 17 Jul, 2012 1 commit
  3. 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
  4. 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
  5. 01 Mar, 2012 1 commit
  6. 11 Nov, 2011 1 commit
    • Yaowu Xu's avatar
      changed function name for clarity · e01b3925
      Yaowu Xu authored
      The dequantizer functions for 2nd order haar block had confusing 8x8
      in their names. this commit fixed their name to avoid confusion.
      
      Change-Id: I6ae4e7888330865f831436313637d4395b1fc273
      e01b3925
  7. 21 Jul, 2011 1 commit
    • Yaowu Xu's avatar
      fix more merge issues · 8c31484e
      Yaowu Xu authored
      With this fix, the experimental branch now builds and encodes correctly
      with the following two configure options respectively:
      --enable-experimental --enable-t8x8
      --enable-experimental
      
      Change-Id: I3147c33c503fe713a85fd371e4f1a974805778bf
      8c31484e
  8. 20 Jul, 2011 1 commit
  9. 10 Feb, 2011 1 commit
    • John Koleszar's avatar
      Fix relative include paths · 02321de0
      John Koleszar authored
      Allow compiling without adding vp8/{common,encoder,decoder} to the
      include paths.
      
      Change-Id: Ifeb5dac351cdfadcd659736f5158b315a0030b6c
      02321de0
  10. 09 Sep, 2010 1 commit
  11. 23 Aug, 2010 1 commit
    • Fritz Koenig's avatar
      Rework idct calling structure. · 93c32a55
      Fritz Koenig authored
      Moving the eob structure allows for a non-struct based
      function to handle decoding an entire mb of
      idct/dequant/recon data.  This allows for SIMD functions
      to idct/dequant/recon multiple blocks at once.
      
      SSE2 implementation gives 3% gain on Atom.
      
      Change-Id: I8a8f3efd546ea4e0535f517d94f347cfb737c9c2
      93c32a55
  12. 26 Jul, 2010 1 commit
    • Johann's avatar
      update arm idct functions · 56f5a9a0
      Johann authored
      Jeff Muizelaar posted some changes to the idct/reconstruction c code.
      This is the equivalent update for the arm assembly.
      
      This shows a good boost on v6, and a minor boost on neon.
      Here are some numbers for highway in qcif, 2641 frames:
      HEAD neon: ~161 fps
      new neon:  ~162 fps
      HEAD v6:   ~102 fps
      new v6:    ~106 fps
      
      The following functions have been updated for armv6 and neon:
      vp8_dc_only_idct_add
      vp8_dequant_idct_add
      vp8_dequant_dc_idct_add
      
      Conflicts:
      
      	vp8/decoder/arm/armv6/dequantdcidct_v6.asm
      	vp8/decoder/arm/armv6/dequantidct_v6.asm
      
      Resolved by removing these files. When I rewrote the functions, I also
      moved the files to dequant_dc_idct_v6.asm/dequant_idct_v6.asm
      
      Change-Id: Ie3300df824d52474eca1a5134cf22d8b7809a5d4
      56f5a9a0
  13. 23 Jul, 2010 1 commit
    • Jeff Muizelaar's avatar
      Combine idct and reconstruction steps · b2fa74ac
      Jeff Muizelaar authored
      This moves the prediction step before the idct and combines the idct and
      reconstruction steps into a single step. Combining them seems to give an
      overall decoder performance improvement of about 1%.
      
      Change-Id: I90d8b167ec70d79c7ba2ee484106a78b3d16e318
      b2fa74ac
  14. 18 Jun, 2010 1 commit
    • John Koleszar's avatar
      cosmetics: trim trailing whitespace · 94c52e4d
      John Koleszar authored
      When the license headers were updated, they accidentally contained
      trailing whitespace, so unfortunately we have to touch all the files
      again.
      
      Change-Id: I236c05fade06589e417179c0444cb39b09e4200d
      94c52e4d
  15. 04 Jun, 2010 1 commit
  16. 18 May, 2010 1 commit