Dirac

A new release of Schrödinger is available. Schrödinger (or “schro”
for short) is a cross-platform implementation of the Dirac video
compression specification as a C library. Many media frameworks
such as GStreamer and ffmpeg and applications such as VLC use schro
to encode and decode Dirac video.

Information: diracvideo.org/
Download:
diracvideo.org/download/schroedinger/schroedinger-1.0.10.tar.gz

The Dirac project maintains two encoder implementations: dirac-research,
a research encoder, and Schrödinger, which is meant for user applications.
Schrödinger outperforms dirac-research in most encoding situations, both
in terms of encoding speed and visual quality.

Roadmap: Only a few people are working on schro, and only part time,
so new features will happen only slowly.

Contributors to this release:

David Schleef (Entropy Wave)

Information about Orc:

code.entropywave.com/projects/orc/

New in 1.0.10
=============

– Build fixes on various platforms
– Speed increases for low-delay syntax
– Fix unaligned access in orc code, which was uncovered by a recent
Orc bug fix. Bump orc requirement to 0.4.10, which makes sure
everyone works right.
– No encoder changes

A new release of Schrödinger is available. Schrödinger (or “schro” for short) is a cross-platform implementation of the Dirac video compression specification as a C library. Many media frameworks such as GStreamer and ffmpeg and applications such as VLC use schro to encode and decode Dirac video.

Information: diracvideo.org/
Download: diracvideo.org/download/schroedinger/schroedinger-1.0.9.tar.gz

The Dirac project maintains two encoder implementations: dirac-research, a research encoder, and Schrödinger, which is meant for user applications. As of this release, Schrödinger outperforms dirac-research in most encoding situations, both in terms of encoding speed and visual quality.

It’s been a long time since the last release, and there have been a *lot* of changes.  This is an exciting release: most of the encoding tools in dirac-research have been ported over to Schrödinger, so now schro has the same or better compression efficiency as dirac-research. Second, we’ve switched over to using Orc instead of liboil for signal processing code.  Dirac is a very configurable format, and normally would require thousands of lines of assembly code — Orc generates this at runtime from simple rules.  (Hey, it was easier to write Orc than write all that assembly!)

Third, we now have an encoder quality testing system in place to check how well new encoding tools work and to make sure bugs that affect quality are quickly fixed.

Roadmap:  Only a few people are working on schro, and only part time, so new features will happen only slowly.  However, now that merging is done and the release is out, there are several new features that are easy to add that will improve encoder quality.  We’d like to get back to more frequent releases, perhaps one a month, introducing a new encoder feature each time.

Other News: Portions of the Dirac specification are now standardized as SMPTE VC-2.  VC-2 is mostly used in high bit rate applications, such as intermediate formats for editing and storage and a low delay format for studio application.

Contributors to this release:

Andrea Gabriellini (BBC)
Anuradha Suraparaju (BBC)
David Schleef (Entropy Wave)

Information about Orc:

code.entropywave.com/projects/orc/

New in 1.0.9

• Orc: Complete conversion to Orc and removal of liboil dependency.
• Added a lot of orc code to make things faster.  A lot faster.
• New motion vector generation, enabled by default.
• New CBR rate control, enabled by default.
• New scene change detection, enabled by default.
• Encoder went through several rounds of tuning, improving quality greatly.
• New encoder setting “force-profile”.  Allows easy access to one of three VC-2 profiles (vc2_low_delay, vc2_simple, vc2_main) for intermediate coding.  Default is same as before: long-GOP Dirac.
• Improved lossless encoding.  Works in concert with force-profile.

A new release of Schrödinger is available. Schrödinger (or “schro”
for short) is a cross-platform implementation of the Dirac video
compression specification as a C library. Many media frameworks
such as GStreamer and ffmpeg use schro to encode and decode Dirac
video.

Information: diracvideo.org/
Download:
diracvideo.org/download/schroedinger/schroedinger-1.0.7.tar.gz

The Dirac project maintains two encoder implementations: dirac-research,
a research encoder, and Schrödinger, which is faster but lower quality.

Schroedinger 1.0.7 is primarily a bugfix release.

New in this release:

– Change encoder default to constant quality, quality=5.0
– Fix several encoding and decoding bugs in the GStreamer elements
and base classes.
– Fix starting/stopping of worker threads
– Port recent threading changes to all backends
– Sanitize invalid clean area in sequence header
– Protect against unexpected backwards skips of picture number
– Discard dangling fields at EOS
– Various other fixes.

A new release of Schrödinger is available. Schrödinger (or “schro” for short) is a cross-platform implementation of the Dirac video compression specification as a C library. Many media frameworks such as GStreamer and ffmpeg use schro to encode and decode Dirac video.

Information: diracvideo.org/
Download: diracvideo.org/download/schroedinger/schroedinger-1.0.6.tar.gz

The Dirac project maintains two encoder implementations: dirac-research, a research encoder, and Schrödinger, which is faster but lower quality. Some encoding features from dirac-research have been moved to schro for this release, more will be in future releases.

New in this release:

– Requires liboil-0.3.16
– New configure flag '–disable-encoder' useful for embedded
systems that don't require the encoder.
– New constant-quality encoding mode, enabled by setting the encoder
setting 'rate-control' to 6, and adjusting 'quality' from 0 to 10.
(Interesting range is 3-7).
– Various encoder improvements
– Speed improvements in decoder
– API additions for parsing streams in the decoder
– API improvements handling interlaced video
– Rewrite of the GStreamer elements, including new base classes
for video encoding and decoding
– Moved extra GStreamer elements to Cog
– Experimental code that uses Orc instead of liboil (–enable-orc)

The release tar-ball can be downloaded from diracvideo.org/download/dirac-research or sourceforge.net/projects/dirac.

Changes is this release are:
- Compliance with Dirac Bytestream specification 2.2.3
- Improved motion estimation.
- Improved compression efficiency at low bit-rates and small pictures
- Fixed bugs in DC subband handling
- New 422 <-> 420 conversion utilities for interlaced video.
- DirectShow Filter released to be able to play back Dirac v2.2.3 files in Window Media Player and
MPlayer Classic
- New utility ffmpeg2dirac released. This utility transcodes any multimedia format that can be decoded
by FFmpeg into Dirac (for video) and Vorbis (audio) muxed in Ogg.

I've written a brief white paper on speeding up the arithmetic decoding and encoding processes in Dirac – it's at diracvideo.org/download/arith-speedups/arith-speedups.pdf. Hopefully it'll be the first in a series of documents of this sort.

A new major release of VLC media player has been made this week that includes support for decoding Dirac video using the Schroedinger library. VLC provides cross platform video playback, encoding and multiplexing functions for a wide variety of media types.

You can download the new version of VLC from www.videolan.org.

VLC 0.9.2 can decode Dirac video multiplexed into Ogg or MPEG Transport Stream containers, in addition to raw Dirac bytestreams. Work is continuing to add extra Dirac functionality to VLC, including extra container formats, multiplexing and encoding.

A stable version of the dirac-research codebase, Dirac 1.0.0, has been released. The release tar-ball can be downloaded from diracvideo.org/download/dirac-research or sourceforge.net/projects/dirac.

Changes is this release are:
- Compliance with Dirac Bytestream specification 2.2.2
- Adaptive GOP structure
- Improved motion estimation.
- Improved pre-filtering.
- Major code refactor of encoder classes.
- Added conversion utility for horizontal 3/4 filtering.
- DirectShow Filter released to be able to play back Dirac v2.2.2 files
raw bytestreams and Dirac wrapped in AVI in Windows Media Player and
MPlayer Classic.

We have received confirmation of the codec identifier 'drac' for use in the ISO media file format and QuickTime. Also, an Object Type Indication for use in the MPEG4 systems layer has been assigned for Dirac video.

See www.mp4ra.org/codecs.html for details of the registration.

We received confirmation today that the format identifier for encapsulating Dirac video within MPEG2 transport streams has been registered with the SMPTE.

See smpte-ra.org/mpegreg/drac.html for the official registration.