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Dirac video codec 1.0 released
The Schrödinger project has announced the availability of the 1.0 version of the Dirac video codec. "Schrödinger core is implemented in ANSI C with further assembly level optimisations provided through the liboil optimisation library. The Schrödinger decoding and encoding components offer a stable ABI for developers which will enable easy integration of Dirac support for application and media framework developers. The Schrödinger project also includes a set of GStreamer plugins as an example of how to use the Schrödinger library in a modern multimedia framework."
(thanks to Timo Jyrinki)
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Dirac Posted Mar 10, 2008 16:27 UTC (Mon) by larryr (guest, #4030) [Link] Dirac is a royalty-free video codec created by BBC Research & Innovation and is the first mainstream codec using next generation wavelet technology... Dirac is an open technology-- removing licensing costs on software, hardware and content flow. "We see a powerful open source ally in the BBC...." commented Monty Montgomery, creator of Ogg Vorbis and Xiph.org."
Dirac Posted Mar 10, 2008 16:33 UTC (Mon) by jake (editor, #205) [Link] > Dirac is a royalty-free video codec ... Your point is valid. I have changed the title and text to at least give readers some idea that it is a video codec. I need to be more careful about context when putting those items together, thanks! jake
Dirac video codec 1.0 released Posted Mar 10, 2008 16:34 UTC (Mon) by pointwood (guest, #2814) [Link] That's very cool! I have high hopes for Dirac, but I couldn't find any test/example videos, anyone know of any?
Dirac video codec 1.0 released Posted Mar 10, 2008 17:31 UTC (Mon) by leoc (subscriber, #39773) [Link] How hard did you look? A google search of "dirac sample video" returned a pointer to the sourceforge page with sample videos: http://sourceforge.net/project/showfiles.php?group_id=102...
Dirac video codec 1.0 released Posted Mar 10, 2008 17:39 UTC (Mon) by pointwood (guest, #2814) [Link] Well, if I read that correctly they are from 2004, more than 3 years old. I would think a lot had happened since then.
Dirac video codec 1.0 released Posted Mar 12, 2008 4:03 UTC (Wed) by dirac (guest, #47842) [Link] The sample videos on Sourceforge are uncompressed data to be used for testing the Dirac encoder implementation. Section 4.2 in the README that comes with the software describes how to convert the sample data to the Planar YUV formats supported by Dirac. Once converted they can be used as input to the Dirac encoder.
Dirac video codec 1.0 released Posted Mar 11, 2008 11:29 UTC (Tue) by lamikr (guest, #2289) [Link]
Hi
I tested it yesterday in Mandriva 2008.
Hopefully these "Aunt Tillie" steps are useful also for others.
1) Install gstreamer0.10-devel
- urpmi libgstreamer0.10-devel
2) download, build and install the latest liboil source package
- ./autogen.sh
- make & make install
3) download, build and install the latest Schrödinger dirac decocer
with gstreamer plugin
- ./autogen.sh
- make (if gstreamer0.10 was recognized it will build gstreamer plug-in under gst
directory)
- make install
--> You should have:
lamikr@pia gstreamer-0.10]$ ls -la /usr/lib/gstreamer-0.10/libgstschro.*
-rwxr-xr-x 1 root root 1047 2008-03-10 18:51 /usr/lib/gstreamer-0.10/libgstschro.la*
-rwxr-xr-x 1 root root 264989 2008-03-10 18:51 /usr/lib/gstreamer-0.10/libgstschro.so*
4) Get some dirac file
- transfered video clip from my videocamera over firewire with Kino to DV file
- converted DV file to mp4 file with Kino (oggconvert did not handle DV files directly)
- searched oggconvert-0.3.1.tar.gz from internet (python gui frontend app)
- extracted oggconvert-0.3.1.tar.gz (can be launched from any directory)
- selected mp4 file for the source in oggconvert
- selected Dirac as a target format
- selected output file name and pressed convert
--> dirac file with ogv extension was created
5) Play the dirac file with gstreamer plug-in installed in step (3)
- gst-launch-0.10 playbin uri=file:///home/lamikr/kino/swamps_on_lake_in_winter.ogv
--> video with picture opened
Mika
Dirac video codec 1.0 released Posted Mar 11, 2008 0:23 UTC (Tue) by djabsolut (guest, #12799) [Link] They seem to use arithmetic coding to compress the quantised wavelet coefficients. If I recall correctly, arithmetic coding was first patented by IBM, and there is a whole bunch of associated patents. BBC must be walking on a very tight rope.
Dirac video codec 1.0 released Posted Mar 11, 2008 3:55 UTC (Tue) by eru (subscriber, #2753) [Link] Many of them are rather old patents. E.g. from your list, IBM's 4905297 "Arithmetic coding encoder and decoder system" was applied for in 1988-11-18, so in jurisdictions that count 20 years from the filing date like all European countries do, it would expire later this year (I am not sure if this is the relevant date for the non-US patents, but in any case the expiry is not too far off, maybe next year then). The Dirac developers may be counting on that by the time the codec sees widespread use, arithmetic coding patents that might cover it are no longer a problem.
Dirac video codec 1.0 released Posted Mar 11, 2008 17:17 UTC (Tue) by jd (guest, #26381) [Link] Software patents aren't recognized or legal in Europe. My guess is that the BBC is on very safe grounds - in Europe - but that Dirac has potential problems in the USA. (Even if the patents have expired, your average website owner or distro developer can't afford the lawyers. If the BBC muscled in to back Dirac users, or growled loud enough, that might help, but I don't recall seeing them do that. If anything, I seem to recall the BBC being rather timid when being directly hastled for putting their own concerts online.)
Expired patents Posted Mar 12, 2008 9:32 UTC (Wed) by eru (subscriber, #2753) [Link] Even if the patents have expired, your average website owner or distro developer can't afford the lawyers.Why should they need lawyers because of the expired patents? In some ways code known to be covered by an expired patent is on "safer ground" than code that may or may not be covered by a non-expired patent. What would be useful is if BBC or some major distro maker funded and published a professional patent analysis of the codec to find out when exactly it becomes unencumbered by patents (or if it already is). In fact it would be nice to see this done for other important codecs as well. Some people have claimed MP3 becomes unencumbered in a few years. I wonder if its predecessor MP2 (used in some DVDs, VCD, and DVB and thus very relevant to Linux multimedia) already is?
Dirac video codec 1.0 released Posted Mar 12, 2008 9:12 UTC (Wed) by tim.borer (guest, #51030) [Link] We are often asked about patents and, in particular, about arithmetic coding patents. Clearly we are aware of patents surrounding arithmetic coding and have been very careful to avoid them. We have conducted a literature search and base our arithmetic coder on prior art literature dating back to Shannons 1948 A Mathematical Theory of Communications and more directly to Rissanen & Langdons 1979 Arithmetic Coding in the IBM Journal of Research & Development as well as other literature. Patents in the US (prior to 1995) expire 17 years after grant. If there are any basic patents on arithmetic coding they have already expired or will do so soon. But, actually, we dont think there are patents on the basic concept of arithmetic coding. The patents that do exist are on practical implementations and optimisations. Most arithmetic coding patents relate to ways of avoiding multiplies and the ways of gathering symbol statistics in an efficient way that allows the use of multiplier less implementations. Bear in mind that these patents were taken out in the late 1970s and early 1980s when avoiding multipliers was a big deal. We have taken the basic concepts and produced our own version of arithmetic coding. Our version doesnt seek to avoid the use of multiplication. This is because there is no need with modern CPUs and modern (FPGA) hardware to do so, Using multipliers no longer incurs a performance penalty. That is something that has changed in the more than 20 years since arithmetic coding emerged. Since we dont seek to avoid multiplies in our arithmetic coding the claims on optimised implementations do not apply. Of course there may be those that think they have patents on the basic concepts. But, if challenged, we can produce prior art dating back many years that would prove such patents to be invalid. Even though we havent sought to optimise our arithmetic coder by eliminating multiplies we have, nevertheless, done considerable optimisation. The basic arithmetic coder is very simple and produces results that are comparable to those obtained by the arithmetic coder used in H264. We also have the advantage that arithmetic coding in Dirac is easy to parallelise, in contrast to H264. This allows us the potential for considerable software optimisation and also allows us to achieve higher bit rates (useful for professional applications). We could have patented our arithmetic coder. We chose not to do so because to patent it would have been contrary to the basic principles of the Dirac project. Our arithmetic coder is now published in our source code and so can not, now, be patented. We are confident that the intellectual property in embodied in Dirac, including that in arithmetic coding, does not require a patent licence, in Europe, the US or elsewhere.
Dirac video codec 1.0 released Posted Mar 12, 2008 15:18 UTC (Wed) by djabsolut (guest, #12799) [Link] Tim, many thanks for the considered response.
Dirac video codec 1.0 released Posted Mar 11, 2008 6:20 UTC (Tue) by colesen (guest, #26593) [Link] The sourceforge page has Dirac at release 0.9.1. Is the Schroedinger project a fork? a takeover? or has the sf page just not been updated yet?
Dirac video codec 1.0 released Posted Mar 11, 2008 7:21 UTC (Tue) by aleXXX (subscriber, #2742) [Link] Schroedinger is the high-performance implementation of the Dirac codec. AFAIK Dirac also has codec software, but this isn't focussed on performance, but just to demonstrate how it works. Alex
Dirac video codec 1.0 released Posted Mar 11, 2008 8:28 UTC (Tue) by andka (subscriber, #974) [Link] See here: http://dirac.sourceforge.net/ Quote: The purpose of the Dirac codebase has changed over time. It is no longer intended as the basis of a real-time practical implementation: for that you want Schrodinger. End of quote
Dirac video codec 1.0 released Posted Mar 12, 2008 9:22 UTC (Wed) by tim.borer (guest, #51030) [Link] The Schro coder is an optimised version of the Dirac codec. It is an independent implementation, not a fork. The development has been supported by the BBC who have been working with Fluendo to produce Schro. We are currently working to ensure that both Schro and Dirac are interoperable and conform to the specification. Schro and Dirac are currently interoperable and we code video using Dirac and play back with the Schro decoder. Schro is an implementation of Dirac. Both codec implementations have their own advantages and disadvanatges, particularly the coders. The Dirac coder, currently, has the edge on the Schro coder in terms of compression performance, but the Schro coder is faster. We will be working on the Schro coder to improve its compression performance over the next few months. Sometime later in the year I expect the Schro coder to equal the compression performance of the Dirac coder. We intend to maintain the Dirac codebase, at least for the time being. I expect another release of Dirac (0.9.2) in a few weeks and this will not be the last. Dirac has an advantage as an experimental test bed. Improvements incorporated in Dirac will probably later be integrated with Schro. Nevertheless Dirac and Schro will remain interoperable.
Dirac video codec 1.0 released Posted Mar 13, 2008 4:52 UTC (Thu) by zooko (subscriber, #2589) [Link] Sweet -- Schrödinger 1.0 is already in Ubuntu Hardy? http://packages.ubuntu.com/hardy/libschroedinger-1.0-0 That was fast.
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