1. 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
  2. 22 Sep, 2011 1 commit
  3. 24 Aug, 2011 1 commit
    • Scott LaVarnway's avatar
      Removed bmi copy to/from BLOCKD · b870947d
      Scott LaVarnway authored
      for SPLITMV and B_PRED modes.  Modified code to use the bmi
      found in mode_info_context instead of BLOCKD.  On the decode
      side, the uvmvs are calculated only when required, instead of
      every macroblock.  This is WIP. (bmi should eventually be
      removed from BLOCKD)
      Small performance gains noticed for RT encodes and decodes.(VGA)
      
      Change-Id: I2ed7f0fd5ca733655df684aa82da575c77a973e7
      b870947d
  4. 22 Jul, 2011 2 commits
    • Johann's avatar
      fix sharpness bug and clean up · a04ed0e8
      Johann authored
      sharpness was not recalculated in vp8cx_pick_filter_level_fast
      
      remove last_filter_type. all values are calculated, don't need to update
      the lfi data when it changes.
      
      always use cm->sharpness_level. the extra indirection was annoying.
      
      don't track last frame_type or sharpness_level manually. frame type
      only matters for motion search and sharpness_level is taken care of in
      frame_init
      
      move function declarations to their proper header
      
      Change-Id: I7ef037bd4bf8cf5e37d2d36bd03b5e22a2ad91db
      a04ed0e8
    • Yunqing Wang's avatar
      Preload reference area to an intermediate buffer in sub-pixel motion search · 20bd1446
      Yunqing Wang authored
      In sub-pixel motion search, the search range is small(+/- 3 pixels).
      Preload whole search area from reference buffer into a 32-byte
      aligned buffer. Then in search, load reference data from this buffer
      instead. This keeps data in cache, and reduces the crossing cache-
      line penalty. For tulip clip, tests on Intel Core2 Quad machine(linux)
      showed encoder speed improvement:
        3.4%   at --rt --cpu-used =-4
        2.8%   at --rt --cpu-used =-3
        2.3%   at --rt --cpu-used =-2
        2.2%   at --rt --cpu-used =-1
      
      Test on Atom notebook showed only 1.1% speed improvement(speed=-4).
      Test on Xeon machine also showed less improvement, since unaligned
      data access latency is greatly reduced in newer cores.
      
      Next, I will apply similar idea to other 2 sub-pixel search functions
      for encoding speed > 4.
      
      Make this change exclusively for x86 platforms.
      
      Change-Id: Ia7bb9f56169eac0f01009fe2b2f2ab5b61d2eb2f
      20bd1446
  5. 13 Jun, 2011 1 commit
  6. 02 Jun, 2011 1 commit
    • Scott LaVarnway's avatar
      Removed B_MODE_INFO · 773768ae
      Scott LaVarnway authored
      Declared the bmi in BLOCKD as a union instead of B_MODE_INFO.
      Then removed B_MODE_INFO completely.
      
      Change-Id: Ieb7469899e265892c66f7aeac87b7f2bf38e7a67
      773768ae
  7. 26 May, 2011 1 commit
  8. 24 May, 2011 1 commit
    • Scott LaVarnway's avatar
      MODE_INFO size reduction · e11f21af
      Scott LaVarnway authored
      Declared the bmi in MODE_INFO as a union instead of B_MODE_INFO.
      This reduced the memory footprint by 518,400 bytes for 1080
      resolutions.  The decoder performance improved by ~4% for the
      clip used and the encoder showed very small improvements. (0.5%)
      This reduction was first mentioned to me by John K. and in a
      later discussion by Yaowu.
      This is WIP.
      
      Change-Id: I8e175fdbc46d28c35277302a04bee4540efc8d29
      e11f21af
  9. 12 May, 2011 1 commit
    • Scott LaVarnway's avatar
      Using int_mv instead of MV · 6b25501b
      Scott LaVarnway authored
      The compiler produces better assembly when using int_mv
      for assignments.  The compiler shifts and ors the two 16bit
      values when assigning MV.
      
      Change-Id: I52ce4bc2bfbfaf3f1151204b2f21e1e0654f960f
      6b25501b
  10. 21 Apr, 2011 1 commit
    • Scott LaVarnway's avatar
      Removed dc_diff from MB_MODE_INFO · 3698c1f6
      Scott LaVarnway authored
      The dc_diff flag is used to skip loopfiltering.  Instead
      of setting this flag in the decoder/encoder, we now check
      for this condition in the loopfilter.
      
      Change-Id: Ie2b9cdf9e0f4e8b932bbd36e0878c05bffd28931
      3698c1f6
  11. 20 Apr, 2011 1 commit
  12. 24 Feb, 2011 1 commit
  13. 19 Jan, 2011 1 commit
    • Henrik Lundin's avatar
      Implement error tracking in the decoder · 67fb3a51
      Henrik Lundin authored
      A new vpx_codec_control called VP8D_GET_FRAME_CORRUPTED. The output
      from the function is non-zero if the last decoded frame contains
      corruption due to packet losses.
      
      The decoder is also modified to accept encoded frames of zero length.
      A zero length frame indicates to the decoder that one or more frames
      have been completely lost. This will mark the last decoded reference
      buffer as corrupted. The data pointer can be NULL if the length is
      zero.
      
      Change-Id: Ic5902c785a281c6e05329deea958554b7a6c75ce
      67fb3a51
  14. 28 Oct, 2010 2 commits
    • Timothy B. Terriberry's avatar
      Eliminate more warnings. · 97b766a4
      Timothy B. Terriberry authored
      This eliminates a large set of warnings exposed by the Mozilla build
       system (Use of C++ comments in ISO C90 source, commas at the end of
       enum lists, a couple incomplete initializers, and signed/unsigned
       comparisons).
      It also eliminates many (but not all) of the warnings expose by newer
       GCC versions and _FORTIFY_SOURCE (e.g., calling fread and fwrite
       without checking the return values).
      There are a few spurious warnings left on my system:
      
      ../vp8/encoder/encodemb.c:274:9: warning: 'sz' may be used
       uninitialized in this function
      gcc seems to be unable to figure out that the value shortcut doesn't
       change between the two if blocks that test it here.
      
      ../vp8/encoder/onyx_if.c:5314:5: warning: comparison of unsigned
       expression >= 0 is always true
      ../vp8/encoder/onyx_if.c:5319:5: warning: comparison of unsigned
       expression >= 0 is always true
      This is true, so far as it goes, but it's comparing against an enum,
       and the C standard does not mandate that enums be unsigned, so the
       checks can't be removed.
      
      Change-Id: Iead6cd561a2afaa3d801fd63f1d8d58953da7426
      97b766a4
    • Timothy B. Terriberry's avatar
      Eliminate more warnings. · c4d7e5e6
      Timothy B. Terriberry authored
      This eliminates a large set of warnings exposed by the Mozilla build
       system (Use of C++ comments in ISO C90 source, commas at the end of
       enum lists, a couple incomplete initializers, and signed/unsigned
       comparisons).
      It also eliminates many (but not all) of the warnings expose by newer
       GCC versions and _FORTIFY_SOURCE (e.g., calling fread and fwrite
       without checking the return values).
      There are a few spurious warnings left on my system:
      
      ../vp8/encoder/encodemb.c:274:9: warning: 'sz' may be used
       uninitialized in this function
      gcc seems to be unable to figure out that the value shortcut doesn't
       change between the two if blocks that test it here.
      
      ../vp8/encoder/onyx_if.c:5314:5: warning: comparison of unsigned
       expression >= 0 is always true
      ../vp8/encoder/onyx_if.c:5319:5: warning: comparison of unsigned
       expression >= 0 is always true
      This is true, so far as it goes, but it's comparing against an enum, and the C
       standard does not mandate that enums be unsigned, so the checks can't be
       removed.
      
      Change-Id: Iaf689ae3e3d0ddc5ade00faa474debe73b8d3395
      c4d7e5e6
  15. 22 Oct, 2010 1 commit
    • Timothy B. Terriberry's avatar
      Convert [4][4] matrices to [16] arrays. · 8f75ea6b
      Timothy B. Terriberry authored
      Most of the code that actually uses these matrices indexes them as
       if they were a single contiguous array, and coverity produces
       reports about the resulting accesses that overflow the static
       bounds of the first row.
      This is perfectly legal in C, but converting them to actual [16]
       arrays should eliminate the report, and removes a good deal of
       extraneous indexing and address operators from the code.
      
      Change-Id: Ibda479e2232b3e51f9edf3b355b8640520fdbf23
      8f75ea6b
  16. 14 Oct, 2010 1 commit
    • Yunqing Wang's avatar
      Fix one gcc compiler warning · 7804befb
      Yunqing Wang authored
      ../libvpx/vp8/encoder/bitstream.c: In function ‘pack_inter_mode_mvs’:
      ../libvpx/vp8/encoder/bitstream.c:1026: warning: array subscript has type ‘char’
      
      Change-Id: Ic77491e0a172fa1821e5b3e914d0dc41fe87c00f
      7804befb
  17. 29 Sep, 2010 1 commit
    • John Koleszar's avatar
      Fix loopfilter delta zero transitions · b9be7a46
      John Koleszar authored
      Loopfilter deltas are initialized to zero on keyframes in the decoder.
      The values then persist from the previous frame unless an update bit
      is set in the bitstream. This data is not included in the entropy
      data saved by the 'refresh entropy' bit in the bitstream, so it is
      effectively an additional contextual element beyond the 3 ref-frames
      and the entropy data.
      
      The encoder was treating this delta update bit as update-if-nonzero,
      meaning that the value would be refreshed even if it hadn't changed,
      and more significantly, if the correct value for the delta changed
      to zero, the update wouldn't be sent, and the decoder would preserve
      the last (presumably non-zero) value.
      
      This patch updates the encoder to send an update only if the value
      has changed from the previously transmitted value. It also forces the
      value to be transmitted in error resilient mode, to account for lost
      context in the event of lost frames.
      
      Change-Id: I56671d5b42965d0166ac226765dbfce3e5301868
      b9be7a46
  18. 09 Sep, 2010 1 commit
  19. 03 Sep, 2010 1 commit
    • Scott LaVarnway's avatar
      Reduced the size of MB_MODE_INFO · 0de458f6
      Scott LaVarnway authored
      Moved partition_bmi and partition_count out of MB_MODE_INFO and
      placed into MACROBLOCK.  Also reduced the size of other members
      of the MB_MODE_INFO struct.  For 1080p, the memory was reduced
      by 1,209,516 bytes.  The decoder performance appeared to improve
      by 3% for the clip used.
      Note:  The main goal for this change is to improve the decoder
      performance.  The encoder will be revisited at a later date for
      further structure cleanup.
      
      Change-Id: I4733621292ee9cc3fffa4046cb3fd4d99bd14613
      0de458f6
  20. 31 Aug, 2010 1 commit
    • Scott LaVarnway's avatar
      Changed above and left context data layout · e85e6315
      Scott LaVarnway authored
      The main reason for the change was to reduce cycles in the token
      decoder. (~1.5% gain for 32 bit)  This layout should be more
      cache friendly.
      
      As a result of this change, the encoder had to be updated.
      
      Change-Id: Id5e804169d8889da0378b3a519ac04dabd28c837
      Note: dixie uses a similar layout
      e85e6315
  21. 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
  22. 12 Aug, 2010 1 commit
    • Scott LaVarnway's avatar
      Removed unnecessary MB_MODE_INFO copies · 9c7a0090
      Scott LaVarnway authored
      These copies occurred for each macroblock in the encoder and decoder.
      Thetemp MB_MODE_INFO mbmi was removed from MACROBLOCKD.  As a result,
      a large number compile errors had to be fixed.
      
      Change-Id: I4cf0ffae3ce244f6db04a4c217d52dd256382cf3
      9c7a0090
  23. 11 Aug, 2010 1 commit
  24. 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
  25. 09 Jun, 2010 1 commit
    • John Koleszar's avatar
      Remove secondary mv clamping from decode stage · 3085025f
      John Koleszar authored
      This patch removes the secondary MV clamping from the MV decoder. This
      behavior was consistent with limits placed on non-split MVs by the
      reference encoder, but was inconsistent with the MVs generated in the
      split case.
      
      The purpose of this secondary clamping was only to prevent crashes on
      invalid data. It was not intended to be a behaviour an encoder could or
      should rely on. Instead of doing additional clamping in a way that
      changes the entropy context, the secondary clamp is removed and the
      border handling is made implmentation specific. With respect to the
      spec, the border is treated as essentially infinite, limited only by
      the clamping performed on the near/nearest reference and the maximum
      encodable magnitude of the residual MV.
      
      This does not affect any currently produced streams.
      
      Change-Id: I68d35a2fbb51570d6569eab4ad233961405230a3
      3085025f
  26. 04 Jun, 2010 1 commit
  27. 18 May, 2010 1 commit