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+Next Release
+ - Incompatible changes:
+ The AV1 encoder's default keyframe interval changed to 128 from 9999.
+
+2016-04-07 v0.1.0 "AOMedia Codec 1"
+ This release is the first Alliance for Open Media codec.
+2015-11-09 v1.5.0 "Javan Whistling Duck"
+ This release improves upon the VP9 encoder and speeds up the encoding and
+ decoding processes.
+
+ - Upgrading:
+ This release is ABI incompatible with 1.4.0. It drops deprecated VP8
+ controls and adds a variety of VP9 controls for testing.
+
+ The vpxenc utility now prefers VP9 by default.
+
+ - Enhancements:
+ Faster VP9 encoding and decoding
+ Smaller library size by combining functions used by VP8 and VP9
+
+ - Bug Fixes:
+ A variety of fuzzing issues
+
+2015-04-03 v1.4.0 "Indian Runner Duck"
+ This release includes significant improvements to the VP9 codec.
+
+ - Upgrading:
+ This release is ABI incompatible with 1.3.0. It drops the compatibility
+ layer, requiring VPX_IMG_FMT_* instead of IMG_FMT_*, and adds several codec
+ controls for VP9.
+
+ - Enhancements:
+ Faster VP9 encoding and decoding
+ Multithreaded VP9 decoding (tile and frame-based)
+ Multithreaded VP9 encoding - on by default
+ YUV 4:2:2 and 4:4:4 support in VP9
+ 10 and 12bit support in VP9
+ 64bit ARM support by replacing ARM assembly with intrinsics
+
+ - Bug Fixes:
+ Fixes a VP9 bitstream issue in Profile 1. This only affected non-YUV 4:2:0
+ files.
+
+ - Known Issues:
+ Frame Parallel decoding fails for segmented and non-420 files.
+
+2013-11-15 v1.3.0 "Forest"
+ This release introduces the VP9 codec in a backward-compatible way.
+ All existing users of VP8 can continue to use the library without
+ modification. However, some VP8 options do not map to VP9 in the same manner.
+
+ The VP9 encoder in this release is not feature complete. Users interested in
+ the encoder are advised to use the git master branch and discuss issues on
+ libvpx mailing lists.
+
+ - Upgrading:
+ This release is ABI and API compatible with Duclair (v1.0.0). Users
+ of older releases should refer to the Upgrading notes in this document
+ for that release.
+
+ - Enhancements:
+ Get rid of bashisms in the main build scripts
+ Added usage info on command line options
+ Add lossless compression mode
+ Dll build of libvpx
+ Add additional Mac OS X targets: 10.7, 10.8 and 10.9 (darwin11-13)
+ Add option to disable documentation
+ configure: add --enable-external-build support
+ make: support V=1 as short form of verbose=yes
+ configure: support mingw-w64
+ configure: support hardfloat armv7 CHOSTS
+ configure: add support for android x86
+ Add estimated completion time to vpxenc
+ Don't exit on decode errors in vpxenc
+ vpxenc: support scaling prior to encoding
+ vpxdec: support scaling output
+ vpxenc: improve progress indicators with --skip
+ msvs: Don't link to winmm.lib
+ Add a new script for producing vcxproj files
+ Produce Visual Studio 10 and 11 project files
+ Produce Windows Phone project files
+ msvs-build: use msbuild for vs >= 2005
+ configure: default configure log to config.log
+ Add encoding option --static-thresh
+
+ - Speed:
+ Miscellaneous speed optimizations for VP8 and VP9.
+
+ - Quality:
+ In general, quality is consistent with the Eider release.
+
+ - Bug Fixes:
+ This release represents approximately a year of engineering effort,
+ and contains multiple bug fixes. Please refer to git history for details.
+
+
+2012-12-21 v1.2.0
+ This release acts as a checkpoint for a large amount of internal refactoring
+ and testing. It also contains a number of small bugfixes, so all users are
+ encouraged to upgrade.
+
+ - Upgrading:
+ This release is ABI and API compatible with Duclair (v1.0.0). Users
+ of older releases should refer to the Upgrading notes in this
+ document for that release.
+
+ - Enhancements:
+ VP8 optimizations for MIPS dspr2
+ vpxenc: add -quiet option
+
+ - Speed:
+ Encoder and decoder speed is consistent with the Eider release.
+
+ - Quality:
+ In general, quality is consistent with the Eider release.
+
+ Minor tweaks to ARNR filtering
+ Minor improvements to real time encoding with multiple temporal layers
+
+ - Bug Fixes:
+ Fixes multithreaded encoder race condition in loopfilter
+ Fixes multi-resolution threaded encoding
+ Fix potential encoder dead-lock after picture resize
+
+
+2012-05-09 v1.1.0 "Eider"
+ This introduces a number of enhancements, mostly focused on real-time
+ encoding. In addition, it fixes a decoder bug (first introduced in
+ Duclair) so all users of that release are encouraged to upgrade.
+
+ - Upgrading:
+ This release is ABI and API compatible with Duclair (v1.0.0). Users
+ of older releases should refer to the Upgrading notes in this
+ document for that release.
+
+ This release introduces a new temporal denoiser, controlled by the
+ VP8E_SET_NOISE_SENSITIVITY control. The temporal denoiser does not
+ currently take a strength parameter, so the control is effectively
+ a boolean - zero (off) or non-zero (on). For compatibility with
+ existing applications, the values accepted are the same as those
+ for the spatial denoiser (0-6). The temporal denoiser is enabled
+ by default, and the older spatial denoiser may be restored by
+ configuring with --disable-temporal-denoising. The temporal denoiser
+ is more computationally intensive than the spatial one.
+
+ This release removes support for a legacy, decode only API that was
+ supported, but deprecated, at the initial release of libvpx
+ (v0.9.0). This is not expected to have any impact. If you are
+ impacted, you can apply a reversion to commit 2bf8fb58 locally.
+ Please update to the latest libvpx API if you are affected.
+
+ - Enhancements:
+ Adds a motion compensated temporal denoiser to the encoder, which
+ gives higher quality than the older spatial denoiser. (See above
+ for notes on upgrading).
+
+ In addition, support for new compilers and platforms were added,
+ including:
+ improved support for XCode
+ Android x86 NDK build
+ OS/2 support
+ SunCC support
+
+ Changing resolution with vpx_codec_enc_config_set() is now
+ supported. Previously, reinitializing the codec was required to
+ change the input resolution.
+
+ The vpxenc application has initial support for producing multiple
+ encodes from the same input in one call. Resizing is not yet
+ supported, but varying other codec parameters is. Use -- to
+ delineate output streams. Options persist from one stream to the
+ next.
+
+ Also, the vpxenc application will now use a keyframe interval of
+ 5 seconds by default. Use the --kf-max-dist option to override.
+
+ - Speed:
+ Decoder performance improved 2.5% versus Duclair. Encoder speed is
+ consistent with Duclair for most material. Two pass encoding of
+ slideshow-like material will see significant improvements.
+
+ Large realtime encoding speed gains at a small quality expense are
+ possible by configuring the on-the-fly bitpacking experiment with
+ --enable-onthefly-bitpacking. Realtime encoder can be up to 13%
+ faster (ARM) depending on the number of threads and bitrate
+ settings. This technique sees constant gain over the 5-16 speed
+ range. For VC style input the loss seen is up to 0.2dB. See commit
+ 52cf4dca for further details.
+
+ - Quality:
+ On the whole, quality is consistent with the Duclair release. Some
+ tweaks:
+
+ Reduced blockiness in easy sections by applying a penalty to
+ intra modes.
+
+ Improved quality of static sections (like slideshows) with
+ two pass encoding.
+
+ Improved keyframe sizing with multiple temporal layers
+
+ - Bug Fixes:
+ Corrected alt-ref contribution to frame rate for visible updates
+ to the alt-ref buffer. This affected applications making manual
+ usage of the frame reference flags, or temporal layers.
+
+ Additional constraints were added to disable multi-frame quality
+ enhancement (MFQE) in sections of the frame where there is motion.
+ (#392)
+
+ Fixed corruption issues when vpx_codec_enc_config_set() was called
+ with spatial resampling enabled.
+
+ Fixed a decoder error introduced in Duclair where the segmentation
+ map was not being reinitialized on keyframes (#378)
+
+
+2012-01-27 v1.0.0 "Duclair"
+ Our fourth named release, focused on performance and features related to
+ real-time encoding. It also fixes a decoder crash bug introduced in
+ v0.9.7, so all users of that release are encouraged to upgrade.
+
+ - Upgrading:
+ This release is ABI incompatible with prior releases of libvpx, so the
+ "major" version number has been bumped to 1. You must recompile your
+ applications against the latest version of the libvpx headers. The
+ API remains compatible, and this should not require code changes in most
+ applications.
+
+ - Enhancements:
+ This release introduces several substantial new features to the encoder,
+ of particular interest to real time streaming applications.
+
+ Temporal scalability allows the encoder to produce a stream that can
+ be decimated to different frame rates, with independent rate targetting
+ for each substream.
+
+ Multiframe quality enhancement postprocessing can make visual quality
+ more consistent in the presence of frames that are substantially
+ different quality than the surrounding frames, as in the temporal
+ scalability case and in some forced keyframe scenarios.
+
+ Multiple-resolution encoding support allows the encoding of the
+ same content at different resolutions faster than encoding them
+ separately.
+
+ - Speed:
+ Optimization targets for this release included the decoder and the real-
+ time modes of the encoder. Decoder speed on x86 has improved 10.5% with
+ this release. Encoder improvements followed a curve where speeds 1-3
+ improved 4.0%-1.5%, speeds 4-8 improved <1%, and speeds 9-16 improved
+ 1.5% to 10.5%, respectively. "Best" mode speed is consistent with the
+ Cayuga release.
+
+ - Quality:
+ Encoder quality in the single stream case is consistent with the Cayuga
+ release.
+
+ - Bug Fixes:
+ This release fixes an OOB read decoder crash bug present in v0.9.7
+ related to the clamping of motion vectors in SPLITMV blocks. This
+ behavior could be triggered by corrupt input or by starting
+ decoding from a P-frame.
+
+
+2011-08-15 v0.9.7-p1 "Cayuga" patch 1
+ This is an incremental bugfix release against Cayuga. All users of that
+ release are strongly encouraged to upgrade.
+
+ - Fix potential OOB reads (cdae03a)
+
+ An unbounded out of bounds read was discovered when the
+ decoder was requested to perform error concealment (new in
+ Cayuga) given a frame with corrupt partition sizes.
+
+ A bounded out of bounds read was discovered affecting all
+ versions of libvpx. Given an multipartition input frame that
+ is truncated between the mode/mv partition and the first
+ residiual paritition (in the block of partition offsets), up
+ to 3 extra bytes could have been read from the source buffer.
+ The code will not take any action regardless of the contents
+ of these undefined bytes, as the truncated buffer is detected
+ immediately following the read based on the calculated
+ starting position of the coefficient partition.
+
+ - Fix potential error concealment crash when the very first frame
+ is missing or corrupt (a609be5)
+
+ - Fix significant artifacts in error concealment (a4c2211, 99d870a)
+
+ - Revert 1-pass CBR rate control changes (e961317)
+ Further testing showed this change produced undesirable visual
+ artifacts, rolling back for now.
+
+
+2011-08-02 v0.9.7 "Cayuga"
+ Our third named release, focused on a faster, higher quality, encoder.
+
+ - Upgrading:
+ This release is backwards compatible with Aylesbury (v0.9.5) and
+ Bali (v0.9.6). Users of older releases should refer to the Upgrading
+ notes in this document for that release.
+
+ - Enhancements:
+ Stereo 3D format support for vpxenc
+ Runtime detection of available processor cores.
+ Allow specifying --end-usage by enum name
+ vpxdec: test for frame corruption
+ vpxenc: add quantizer histogram display
+ vpxenc: add rate histogram display
+ Set VPX_FRAME_IS_DROPPABLE
+ update configure for ios sdk 4.3
+ Avoid text relocations in ARM vp8 decoder
+ Generate a vpx.pc file for pkg-config.
+ New ways of passing encoded data between encoder and decoder.
+
+ - Speed:
+ This release includes across-the-board speed improvements to the
+ encoder. On x86, these measure at approximately 11.5% in Best mode,
+ 21.5% in Good mode (speed 0), and 22.5% in Realtime mode (speed 6).
+ On ARM Cortex A9 with Neon extensions, real-time encoding of video
+ telephony content is 35% faster than Bali on single core and 48%
+ faster on multi-core. On the NVidia Tegra2 platform, real time
+ encoding is 40% faster than Bali.
+
+ Decoder speed was not a priority for this release, but improved
+ approximately 8.4% on x86.
+
+ Reduce motion vector search on alt-ref frame.
+ Encoder loopfilter running in its own thread
+ Reworked loopfilter to precalculate more parameters
+ SSE2/SSSE3 optimizations for build_predictors_mbuv{,_s}().
+ Make hor UV predict ~2x faster (73 vs 132 cycles) using SSSE3.
+ Removed redundant checks
+ Reduced structure sizes
+ utilize preload in ARMv6 MC/LPF/Copy routines
+ ARM optimized quantization, dfct, variance, subtract
+ Increase chrow row alignment to 16 bytes.
+ disable trellis optimization for first pass
+ Write SSSE3 sub-pixel filter function
+ Improve SSE2 half-pixel filter funtions
+ Add vp8_sub_pixel_variance16x8_ssse3 function
+ Reduce unnecessary distortion computation
+ Use diamond search to replace full search
+ Preload reference area in sub-pixel motion search (real-time mode)
+
+ - Quality:
+ This release focused primarily on one-pass use cases, including
+ video conferencing. Low latency data rate control was significantly
+ improved, improving streamability over bandwidth constrained links.
+ Added support for error concealment, allowing frames to maintain
+ visual quality in the presence of substantial packet loss.
+
+ Add rc_max_intra_bitrate_pct control
+ Limit size of initial keyframe in one-pass.
+ Improve framerate adaptation
+ Improved 1-pass CBR rate control
+ Improved KF insertion after fades to still.
+ Improved key frame detection.
+ Improved activity masking (lower PSNR impact for same SSIM boost)
+ Improved interaction between GF and ARFs
+ Adding error-concealment to the decoder.
+ Adding support for independent partitions
+ Adjusted rate-distortion constants
+
+
+ - Bug Fixes:
+ Removed firstpass motion map
+ Fix parallel make install
+ Fix multithreaded encoding for 1 MB wide frame
+ Fixed iwalsh_neon build problems with RVDS4.1
+ Fix semaphore emulation, spin-wait intrinsics on Windows
+ Fix build with xcode4 and simplify GLOBAL.
+ Mark ARM asm objects as allowing a non-executable stack.
+ Fix vpxenc encoding incorrect webm file header on big endian
+
+
+2011-03-07 v0.9.6 "Bali"
+ Our second named release, focused on a faster, higher quality, encoder.
+
+ - Upgrading:
+ This release is backwards compatible with Aylesbury (v0.9.5). Users
+ of older releases should refer to the Upgrading notes in this
+ document for that release.
+
+ - Enhancements:
+ vpxenc --psnr shows a summary when encode completes
+ --tune=ssim option to enable activity masking
+ improved postproc visualizations for development
+ updated support for Apple iOS to SDK 4.2
+ query decoder to determine which reference frames were updated
+ implemented error tracking in the decoder
+ fix pipe support on windows
+
+ - Speed:
+ Primary focus was on good quality mode, speed 0. Average improvement
+ on x86 about 40%, up to 100% on user-generated content at that speed.
+ Best quality mode speed improved 35%, and realtime speed 10-20%. This
+ release also saw significant improvement in realtime encoding speed
+ on ARM platforms.
+
+ Improved encoder threading
+ Dont pick encoder filter level when loopfilter is disabled.
+ Avoid double copying of key frames into alt and golden buffer
+ FDCT optimizations.
+ x86 sse2 temporal filter
+ SSSE3 version of fast quantizer
+ vp8_rd_pick_best_mbsegmentation code restructure
+ Adjusted breakout RD for SPLITMV
+ Changed segmentation check order
+ Improved rd_pick_intra4x4block
+ Adds armv6 optimized variance calculation
+ ARMv6 optimized sad16x16
+ ARMv6 optimized half pixel variance calculations
+ Full search SAD function optimization in SSE4.1
+ Improve MV prediction accuracy to achieve performance gain
+ Improve MV prediction in vp8_pick_inter_mode() for speed>3
+
+ - Quality:
+ Best quality mode improved PSNR 6.3%, and SSIM 6.1%. This release
+ also includes support for "activity masking," which greatly improves
+ SSIM at the expense of PSNR. For now, this feature is available with
+ the --tune=ssim option. Further experimentation in this area
+ is ongoing. This release also introduces a new rate control mode
+ called "CQ," which changes the allocation of bits within a clip to
+ the sections where they will have the most visual impact.
+
+ Tuning for the more exact quantizer.
+ Relax rate control for last few frames
+ CQ Mode
+ Limit key frame quantizer for forced key frames.
+ KF/GF Pulsing
+ Add simple version of activity masking.
+ make rdmult adaptive for intra in quantizer RDO
+ cap the best quantizer for 2nd order DC
+ change the threshold of DC check for encode breakout
+
+ - Bug Fixes:
+ Fix crash on Sparc Solaris.
+ Fix counter of fixed keyframe distance
+ ARNR filter pointer update bug fix
+ Fixed use of motion percentage in KF/GF group calc
+ Changed condition for using RD in Intra Mode
+ Fix encoder real-time only configuration.
+ Fix ARM encoder crash with multiple token partitions
+ Fixed bug first cluster timecode of webm file is wrong.
+ Fixed various encoder bugs with odd-sized images
+ vp8e_get_preview fixed when spatial resampling enabled
+ quantizer: fix assertion in fast quantizer path
+ Allocate source buffers to be multiples of 16
+ Fix for manual Golden frame frequency
+ Fix drastic undershoot in long form content
+
+
+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!
+