aom/CHANGELOG

2010-10-28 v0.9.5 "Aylesbury"
  Our first named release, focused on a faster decoder, and a better encoder.

  - Upgrading:
    This release incorporates backwards-incompatible changes to the
    ivfenc and ivfdec tools. These tools are now called vpxenc and vpxdec.

    vpxdec
      * the -q (quiet) option has been removed, and replaced with
        -v (verbose). the output is quiet by default. Use -v to see
        the version number of the binary.

      * The default behavior is now to write output to a single file
        instead of individual frames. The -y option has been removed.
        Y4M output is the default.

      * For raw I420/YV12 output instead of Y4M, the --i420 or --yv12
        options must be specified.

          $ ivfdec -o OUTPUT INPUT
          $ vpxdec --i420 -o OUTPUT INPUT

      * If an output file is not specified, the default is to write
        Y4M to stdout. This makes piping more natural.

          $ ivfdec -y -o - INPUT | ...
          $ vpxdec INPUT | ...

      * The output file has additional flexibility for formatting the
        filename. It supports escape characters for constructing a
        filename from the width, height, and sequence number. This
        replaces the -p option. To get the equivalent:

          $ ivfdec -p frame INPUT
          $ vpxdec --i420 -o frame-%wx%h-%4.i420 INPUT

    vpxenc
      * The output file must be specified with -o, rather than as the
        last argument.

          $ ivfenc <options> INPUT OUTPUT
          $ vpxenc <options> -o OUTPUT INPUT

      * The output defaults to webm. To get IVF output, use the --ivf
        option.

          $ ivfenc <options> INPUT OUTPUT.ivf
          $ vpxenc <options> -o OUTPUT.ivf --ivf INPUT


  - Enhancements:
      ivfenc and ivfdec have been renamed to vpxenc, vpxdec.
      vpxdec supports .webm input
      vpxdec writes .y4m by default
      vpxenc writes .webm output by default
      vpxenc --psnr now shows the average/overall PSNR at the end
      ARM platforms now support runtime cpu detection
      vpxdec visualizations added for motion vectors, block modes, references
      vpxdec now silent by default
      vpxdec --progress shows frame-by-frame timing information
      vpxenc supports the distinction between --fps and --timebase
      NASM is now a supported assembler
      configure: enable PIC for shared libs by default
      configure: add --enable-small
      configure: support for ppc32-linux-gcc
      configure: support for sparc-solaris-gcc

  - Bugs:
      Improve handling of invalid frames
      Fix valgrind errors in the NEON loop filters.
      Fix loopfilter delta zero transitions
      Fix valgrind errors in vp8_sixtap_predict8x4_armv6().
      Build fixes for darwin-icc

  - Speed:
      20-40% (average 28%) improvement in libvpx decoder speed,
      including:
        Rewrite vp8_short_walsh4x4_sse2()
        Optimizations on the loopfilters.
        Miscellaneous improvements for Atom
        Add 4-tap version of 2nd-pass ARMv6 MC filter.
        Improved multithread utilization
        Better instruction choices on x86
        reorder data to use wider instructions
        Update NEON wide idcts
        Make block access to frame buffer sequential
        Improved subset block search
        Bilinear subpixel optimizations for ssse3.
        Decrease memory footprint

      Encoder speed improvements (percentage gain not measured):
        Skip unnecessary search of identical frames
        Add SSE2 subtract functions
        Improve bounds checking in vp8_diamond_search_sadx4()
        Added vp8_fast_quantize_b_sse2

  - Quality:
      Over 7% overall PSNR improvement (6.3% SSIM) in "best" quality
      encoding mode, and up to 60% improvement on very noisy, still
      or slow moving source video

        Motion compensated temporal filter for Alt-Ref Noise Reduction
        Improved use of trellis quantization on 2nd order Y blocks
        Tune effect of motion on KF/GF boost in two pass
        Allow coefficient optimization for good quality speed 0.
        Improved control of active min quantizer for two pass.
        Enable ARFs for non-lagged compress

2010-09-02 v0.9.2
  - Enhancements:
      Disable frame dropping by default
      Improved multithreaded performance
      Improved Force Key Frame Behaviour
      Increased rate control buffer level precision
      Fix bug in 1st pass motion compensation
      ivfenc: correct fixed kf interval, --disable-kf
  - Speed:
      Changed above and left context data layout
      Rework idct calling structure.
      Removed unnecessary MB_MODE_INFO copies
      x86: SSSE3 sixtap prediction
      Reworked IDCT to include reconstruction (add) step
      Swap alt/gold/new/last frame buffer ptrs instead of copying.
      Improve SSE2 loopfilter functions
      Change bitreader to use a larger window.
      Avoid loopfilter reinitialization when possible
  - Quality:
      Normalize quantizer's zero bin and rounding factors
      Add trellis quantization.
      Make the quantizer exact.
      Updates to ARNR filtering algorithm
      Fix breakout thresh computation for golden & AltRef frames
      Redo the forward 4x4 dct
      Improve the accuracy of forward walsh-hadamard transform
      Further adjustment of RD behaviour with Q and Zbin.
  - Build System:
      Allow linking of libs built with MinGW to MSVC
      Fix target auto-detection on mingw32
      Allow --cpu= to work for x86.
      configure: pass original arguments through to make dist
      Fix builds without runtime CPU detection
      msvs: fix install of codec sources
      msvs: Change devenv.com command line for better msys support
      msvs: Add vs9 targets.
      Add x86_64-linux-icc target
  - Bugs:
      Potential crashes on older MinGW builds
      Fix two-pass framrate for Y4M input.
      Fixed simple loop filter, other crashes on ARM v6
      arm: fix missing dependency with --enable-shared
      configure: support directories containing .o
      Replace pinsrw (SSE) with MMX instructions
      apple: include proper mach primatives
      Fixed rate control bug with long key frame interval.
      Fix DSO link errors on x86-64 when not using a version script
      Fixed buffer selection for UV in AltRef filtering


2010-06-17 v0.9.1
  - Enhancements:
      * ivfenc/ivfdec now support YUV4MPEG2 input and pipe I/O
      * Speed optimizations
  - Bugfixes:
      * Rate control
      * Prevent out-of-bounds accesses on invalid data
  - Build system updates:
      * Detect toolchain to be used automatically for native builds
      * Support building shared libraries
      * Better autotools emulation (--prefix, --libdir, DESTDIR)
  - Updated LICENSE
      * http://webmproject.blogspot.com/2010/06/changes-to-webm-open-source-license.html


2010-05-18 v0.9.0
  - Initial open source release. Welcome to WebM and VP8!