Slashdot Mirror
Dirac 1.0.0 Released
dylan_- writes "According to their website, 'Dirac is an advanced royalty-free video compression format designed for a wide range of uses, from delivering low-resolution web content to broadcasting HD and beyond, to near-lossless studio editing.' Now a stable version of the dirac-research codebase, Dirac 1.0.0, has been released. The BBC have already successfully used the new codec during the Beijing Olympics and are looking to push it to more general use throughout the organisation. The latest version of VLC (the recently released 0.9.2) has support for Dirac using the Schroedinger library."
Remember when we all used GIF until somebody came out of the closet with a patent claim. How can we be sure about this one?
I tried using the Schrodinger library but I'm uncertain it works. Plus, I can't find my cat.
I see the first 4 bytes are 0xBBCD.
British Broadcasting Corporation Dirac.
From the FAQ:
What are the license conditions?
The Schrodinger software is available under any of the GPLv2, MIT or MPL licences. Libraries may also be used under LGPL.
Sounds like someone wanted there to be no question about whether it was open source.
How does it stack up to other codecs?
Do we need another codec?
http://blindscribblings.com - Tasty pop-culture in conceptual fashion.
I was wondering where I could find some vids to check out quality vs. file sizes and found this index of demo files. Looks great in VLC, quite impressive even at lower bitrates.
I hope I didn't brain my damage.
While it's very cool what the BBC is doing, and it's good to see wavelet technology being pushed, Dirac 1.0 falls extremely short in my tests (at least on animated material at medium bitrates). In the H.264 era, the quality is unacceptable. Here's hoping they'll be able to keep improving it. On the other hand, I know at least one x264 dev who's convinced that OBMC wavelets will never match the quality of MC block-based approaches without a major breakthrough.
We don't need another codec, per se, we need a royalty free codec, that can be legally implemented in FOSS situations, and others without a lot of legal overhead. Assuming it isn't markedly worse than others in performance terms, Dirac qualifies. If by some miracle(class II or greater) mpeg4 were available under such terms, there wouldn't be any point to Dirac; but that isn't exactly likely.
Dirac isn't the only royality-free, patent-unencumbered video codec there is - Xiph's OGG Theora has been around a while already, yet failed to impress quality-wise up until recently. There's some really cool development going on however, and you may see some of the results achieved over there: http://xiphmont.livejournal.com/35363.html
It's noteworthy that the changes made only affect the ENCODER, thus no changes to the DECODER (the part of a codec all applications used to play back files have included) are necessary. This bodes very well for HTML5, which will include some support for Theora on at least Mozilla (and iirc Opera) browsers.
:%s/Open Source/Free Software/g
YTARY!
How does it stack up to other codecs?
As I say below, unfortunately the quality is lacking compared to modern codecs like H.264 and even (dare I say) VC-1. Apparently that's just the nature of using wavelets. While they give a very natural style of compression on still images (JPEG-2000, etc), they do not translate well to moving sequences because, unlike all other current codecs, the image is not broken up into blocks that can then be tracked and diff'd in time. Still, it'll be interesting to follow Dirac, if only because they're taking a radical new approach with only Michael Niedermayer's Snow as a peer.
Could it be that the BBC's slowness to offer HD is related to the fact that most license payers receive their broadcasts via analogue or "Freeview" digital, neither of which currently support it? I guess they have better things to spend their limited budget on.
Nobody else has this sig.
As I state below. Most of codecs performance has to do with the encoder. At 1.0.0 its too early to tell if the format/codec design is limited.
However a great codec without a good encoder is no good at all. But its early days yet considering h.264 has been around for 5+ years.
If information wants to be free, why does my internet connection cost so much?
Dirac employs wavelet compression, instead of the discrete cosine transforms used in most older codecs (such as H.264/MPEG-4 AVC or SMPTE's VC-1). Dirac is one of several projects attempting to apply wavelets to video compression. Others include Rududu [2], Snow and Tarkin. Wavelet compression has already proven its viability in the JPEG 2000 compression standard for photographic images.
Yes it does :|
16mm is a perfectly viable format for 24p HD, so your question is something of a contradiction. Sure, the quality might not be as good as it could be, but it serves a niche market for low budget HD output on 'quality' drama. Comparing the BBC's HD drama output to the stuff in the States is disingenuous, not least because HD penetration in the UK is extremely low but also because shows in the UK tend to run on lower budgets anyway than prime-time US serials.
In a nutshell, yes. HD is also not much of a big deal to the vast majority of television viewers either. The only reason there is such a fuss over it in the United States is mostly because they are rolling out HD and digital at the same time: most of the improvement has come from the change to digital, not HD. In Europe it's not such a big deal because we've already switched to digital. HD is "nice" but it's not the huge leap in visual quality some people would like you to believe.
And I thought that was some kind of UK New Wave artsy Duane Hopkins/dogma thing they were going for.
Once again, I mistake incompetence for artistic innovation.
You are welcome on my lawn.
Someone's evidentially not been watching Top Gear, which features some of the best camera work on TV and film.
The codec is new, give it a few months.
Early DVDs looked like shitty 90% compressed jpegs too, you know.
Windows is not 99% of the world. It is, depending on who you ask, between 88% and 95% of all desktop computer users. Of course, most of those don't give a damn about encoding Dirac files; the proportion of Windows users among highly IT literate, technically minded people is somewhat lower.
Hmmm... "Killer application" drives adoption of platform.
Most people on Windows only consume, not produce.
Flower chase the sunshine.
Stick Men
I downloaded the code from sourceforge and compiled the code using Visual Studio 2008.
Looks like the encoder is distributed in source format only. I could not locate any pre-built binaries.
I am having trouble figuring out what the command-line parameters mean from the README supplied in the source tarball.
This certainly needs better documentation for non technical users.
The samples certainly look impressive. I will try to compare it against my current favorite encoder -- x264 -- over the weekend.
Update: I've been told by the devs that Dirac is optimized for HD live action, wheres my tests have thus far involved SD animated content, so, YMMV. I'll have to try some live action sources next.
Exactly, Matroska is great and all from a freedom standpoint, but technically it's far behind the encumbered ones.
At least we have ogg for audio, it seems like nothing can beat it in terms of quality/bitrate:-)
93rd rule of Slashdot: No matter how obvious my sarcasm is, my comment will be taken seriously by someone.
It's development software; new innovative software tends to be one platform, generally whatever the devs are most comfortable with. I don't know a thing about windows software engineering since early xp, but if I make something cool enough for linux someone else will probably be interested in porting it.
Video processing is commonly done on non-windows platforms because then you don't need a per-computer license for each node in the render farm, and FOSS software can follow an edl as easily as the proprietary stuff that created it. Maybe that's what bbc is using?
Just a guess
93rd rule of Slashdot: No matter how obvious my sarcasm is, my comment will be taken seriously by someone.
I strongly disagree that "most of the improvement has come from the change to digital, not HD". TVs don't magically become a higher resolution when you add a digital decoder! The main benefit(?) of digital has been more channels.
I see a huge difference in quality between SD and HD. The most damaging thing for HD that I've seen is that many retailers used to play SD content on HDTVs, which isn't particularly suited for a TFT/LCD screen and can look terrible.
Matroska is a container, not a codec.
Matroska is not a codec. It is a container format, and it beats any closed-source competitions hands own on features (e.g. as far as I know it is the only format that supports embedding custom TrueType fonts for subtitles).
The best video encoding combo right now is:
- Matroska as the container
- H.264 for video
- Ogg Vorbis for audio
- ASS for subtitles
Those who would give up liberty to obtain working drivers, deserve neither liberty nor working drivers.
Yeah I realized that after I wrote this:-) I meant Theora. Oopsie.
93rd rule of Slashdot: No matter how obvious my sarcasm is, my comment will be taken seriously by someone.
Who on earth modded that insightful? It makes no sense! It's completely wrong. It has nothing to do with the broadcast format, but the recording format. Using 16mm film is FAR, FAR more expensive than HD video.
It also means that other countries are less likely to buy their output. Thus ending in a downward spiral of quality, due to less money being available for production.
The changeover has nothing to do with cost, and everything to do with resistance to change and a erroneous, misguided elitism that film is better. 35mm might be for some things, but 16mm is dead tech, other than as a training medium for 35mm.
Not to mention that Top Gear looks absolutely stunning in HD - check the Polar Special, it is definitive HD demo material.
But the grandparent has a point. Digital terrestial TV is kind-of half baked in most European countries because they went with DVB-T (MPEG 2). (As did my country, Finland). That means that without new boxes the terrestial customers are left with SD until the next "big change". And since the as in the UK and in Finland there are similiar terrestial networks the national TV companies (BBC in the UK, YLE here) are not that interested in producing HD content for cable customers. YLE did the Beijing Games in HD as a test for a small ammount of terrestial customers living withing coverage of one broadcast tower, though.
I'm not an advocate of delaying transition to digital TV, but in countries where there is a strong public tv company (like in UK and in Finland) it might have been better to wait for DVB-T2 and MPEG4 and transition to HD at the same time. Here in Finland YLE promises HD content maybe in 2016, until that it is cable and satellite and no public tv in HD I fear...
And to those who think public TV is crap and I should go for commercial cable / sat receiving anyway: What we have from YLE here is quite good actually - quality news and documentry (of course to be applied with the normal critical thinking and not believing the only source) and for an example recently they bought the rights for all the HBO shows and BBC material is also quite common. HD would be very, very nice, thankyou...
Yes,it is nice to have HD,the problem is that the big companies will ruin it by compressing the hell out of it to squeeze in more channels. personally,seeing as how many artifacts end up in the overly compressed HD,I'd personally rather have uncompressed SD than HD,thank you very much. I'm just lucky I'm on a small cableco that is going to stick with SD until they are finished upgrading their network,which they figure will take around 2 years. New servers,lots of fiber being laid,and with each new piece my Internet connection gets a little faster and snappier. But if all the providers start compressing the hell out of the HD signals I don't see HD adoption taking off. Who in the hell would want HD if they compress it so bad it looks like a low bitrate .wmv? But as always this is my 02c,YMMV
ACs don't waste your time replying, your posts are never seen by me.
Also, try to encode with the newer versions of Theora. It has gotten much improvements in the last year - quality problems were never in the decoding as some will have you believe, but that the encoder pretty much sucked.
Not sure what you expect and I'm no video buff... but it sure looks a LOT better.
(You may still be right, of course. I've just found that 99% of all who state anything about anythings quality usually have formed their opinion once, maybe years ago, and then keep on repeating it).
This came up in yesterday's discussion of the Canonical codec pack.
Standardized codecs, like VC-1 and H.264, have full open specifications and typically even reference source code implementations that can be reused in a variety of ways.
However, they also require patent fees depending on use and jurisdiction.
The issue of free software has always been asserted to be about "speech, not beer" but it seems like there's an assumption that it has to be free as in "speech AND beer." I'm sure all kind of arguments can be made that it should be that way, but everything I've read recently sort of begs that question by conflating the issues of closed source and patent licensing. When to me they look like pretty orthogonal issues; all of the reasons why people say they like open source are still delivered if the source is open, irrespective of whether a patent fee is paid. And MEPG-LA makes patent administration and payment pretty straightforward under RAND terms.
Did I just miss some prior discussions?
My video compression blog
How does Vorbis really compare against AAC? Besides the whole royalty/patent free issue, does Vorbis really beat out AAC? (Ignoring royalty/patent issues here because you also mentioned H264)
been waiting a long time.
I've seen only one episode (vsiting a friend who watches TV more than I do, and who gets more channels), but it made me want to see many more. (The one I saw was about zooming and crunching through East Africa in beaters purchased in-country -- pretty impressive how they all held up, actually, though all suffered pretty badly.)
Thanks for your support, TV licensees of Britain!
timothy
jrnl: http://tinyurl.com/c2l8yr / foes: http://tinyurl.com/ckjno5
What about Dirac being a wavelet based codec that has inter-frame motion compensation? Wavelet is superior to DCT-based codec, like mpeg-1, 2, and h.264. Dirac's inter-frame encoding is also something that motion JPEG 2000 doesn't have.
I once had a signature.
Took me a while to figure I needed to use YUV input. :(
Unfortunately, it looks like Dirac is no match for x264.
Even VC-1 beats Dirac.
How will you use it?
If it's really important to you, don't guess; do your own test. The Hydrogen Audio folks know something about this.
http://wiki.hydrogenaudio.org/index.php?title=Choosing_the_best_codec
These days HD content is more likely to be recorded onto a high end digital video format like HDCAM. Many of the cameras are descended from the old DigiBeta camcorders seen on news cameramens' shoulders. There are also cameras such as the Sony F23, Thomson Grassvalley Viper, the Panavision Genesis and the Arri D20 which bear a closer resemblance to those from the world of film. These are mostly used on features, commercials and music videos.
The main benefit(?) of digital has been more channels.
The main benefit to consumers is less noise in the signal, drastically improving the quality. Resolution isn't the only measure of quality.
Exactly! And "most of the improvement" is more channels! Outside of (a subset of) Slashdot and a few A/V forums, nobody really gives a shit about HD!
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
Hey, I KNEW those Atomic Physics courses I took way back in University would come in handy!
.
Who needs to compress time, when all you hafta do is compress the video.
If I took a video of my cat, and then compressed it with this new codec, would the cat be...
Umm.. never mind...!
.
.
- aqk
F U
The same people that think youtube videos are good enough or even good. Really a lot of people don't see the artifacts. I showed my wife what some look like and she kicked me, because now she can see them too. I also find that when you up the bitrate for "artifact" free encoding, h.264/mpeg4 etc all perform about the same. The differences come out at low bitrate where I'm not all that interested.
If information wants to be free, why does my internet connection cost so much?
Right now Ogg/Vorbis is the overall BEST quality lossy compression codec. Check out the wikipedia page.
The porn-viewing experience just gets better and better.
You seem to be confusing motion estimation/compensation with residual coding. Dirac does break the image into blocks, using overlapped block motion compensation. However, the residual image is coded as a whole, thanks to wavelets. This should greatly reduce blocking artifacts.
Especially since (in Europe at least) most people don't use wall sized TVs and hence don't care all that much about resolution.
Although maybe 70inch diagonal sets may be common in the US... Here I don't know anybody who would see the point of going beyond 35 or 40.
May contain traces of nut.
Made from the freshest electrons.
Strictly speaking, DVB-T defines only the transmission aspects. As such, DVB-T2 may introduce notable changes but it seems to still use the MPEG-2 transport stream and thus will likely refer to the same specifications as DVB-T. It is true that as far as codecs are concerned it was not until 2005 (publication date of ETSI TS 101 154 V1.6.1) that optional support for improved AV codecs was introduced (H.264/AVC and HE AAC, with VC-1 added in version 1.8.1). However, aside from the resulting chicken-or-egg problem, this does not preclude DVB-T stations from using the newer codecs, and some are already doing so.
I too feel that the deployment is somewhat shoddy, but the theory is that there is no need to wait for a big change because buying a new decoder is relatively inexpensive. I don't quite agree because apart from being wasteful it is consumer-unfriendly to discover that an HD TV set sold as DVB-capable doesn't support some (HD) content because of the codec (beside the fact that it might not support HD DVB-T streams at all depending on whether it is HD ready, HD TV, Full HD or whatever the current marketspeak is), and that after somehow upgrading to get over that deficiency one is bound to learn that the system still doesn't support MHP or whatever technology under the DVB umbrella gets highlighted in the following months.
Someone's evidentially not been watching Top Gear, which features some of the best camera work on TV and film.
Yes, well, you know, to some of us a show about cars is about as exciting as a show about computers would be to the general public (look ! it's got wheels ! and seats ! whoohoo ! -- yawn)
May contain traces of nut.
Made from the freshest electrons.
Top Gear isn't about cars, they're just used to give the presenters something to argue about.
"Welcome to our world. We are the wasted youth. And we are the future too." Yes, I know these are stupid lyrics.
According to Wikipedia aoTuV beta 4 Vorbis encoder beats WMA, MP3 and AAC at 64-128 kbit/s.
Those who would give up liberty to obtain working drivers, deserve neither liberty nor working drivers.