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HTML 5, Codecs and the Video Tag

June 20, 2009 Leave a comment

Spending the last two days at the Open Video Conference has been a great experience, lots of interesting speakers and I’ve learned a few things. Perhaps I’ll write more in general later, however it’s worth mentioning, while still fresh in my mind, today’s sessions around royalty-free codecs and the HTML 5 <video> tag.

The main focus of the Royalty Free Codecs session seemed to be around Ogg Theora. Also present though were Sun, speaking about their new Open Media Stack, and David Schleef to represent his work on the Schroedinger Dirac library. I would have loved to hear more about what was happening with Dirac, but the crowd wanted Theora news.

A short demonstation on the projector screen showed H.263/H.264 content versus the same Ogg Theora content at various bit rates, the highest less than 500Kbps. The results, from Theora’s perspective, were very good. Visually I couldn’t pick out any differences on the large screen. I would have liked to see the demonstration done at higher, greater than 1Mbps, bitrates, though. Not the one used today, but a similar demonstration is available here.

Sun did not do themselves any favours at this Conference. A session yesterday gave them time to discuss the process they undertook to ensure there were no IP encumbrance in their new codec and Open Media Stack, but right at the end the key revelation was that they’re unable to Open Source their work.

David did not have much of a chance to talk in depth about Dirac, and I was disappointed not to have gained a better understanding the current development status, and community input velocity around Dirac. He did make a point that the BBC were using Dirac internally, which is true but only to a very small extent. In non-linear editing environments, DVCProHD, AVC-I 100 and ProRes are still the codecs of choice. In my opinion this due to the lack of tools available for Dirac work. Dirac tool development needs a great leap forward if this codec is to gain any significant traction.

The next session had representatives from all major browsers (Firefox, Webkit and Opera), except IE, present to talk about HTML 5 and the new <video> tag.

Firstly, I was particularly interested in the W3C Draft Web Fragments specification. Amongst other things, this will allow playback of just segments of video, based on a time specification in seconds. While not currently possible, if this could be extended to read an embedded timecode track and seek in a frame accurate manner, that would be truly powerful in an open standard.

With Safari on Mac, the <video> tag can be used to playback any video format for which the user has the relevant codec and QuickTime component installed. Thus we have Theora support through the XiphQT component. In the latest version of iMovie, QuickTime Pro and Final Cut Pro, users can now also choose to export or render in Ogg Theora. If only the Dirac QT component was ready.

Metavid developers also demonstrated a cute javascript library embed workaround that covered IE’s lack of support for the <video> tag. Full details are available on the Metavid website, as well as a demonstration of the code in action. Even if you’re browser doesn’t currently support the HTML 5 <video> element, this script will take care of it.

The cross fade is particularly interesting. Do we no longer need to finish clips in a non-linear editor? Can we now perform hard cuts based on an edit decision list and let the browser deal with the fading or finishing element of the job?

Hopefully there’s some exciting times ahead for open source, royalty free video codecs and ubiquity of embedded video on the Web. 

Kdenlive 0.7.4 Released, Makes it Easy to Try

June 20, 2009 Leave a comment

Although released a few weeks ago, the new Kdenlive 0.7.4 version is progressing nicely. The current release notes list the following updates:

  • Compatibility with the new 0.4.x versions of MLT
  • Rendering jobs now start one after another instead of all together
  • Rewritten DVD wizard, allowing for chapters, several buttons in menu and easy preview
  • Start of a transcoding feature, allowing to easily convert a clip in another format
  • Long list of bug fixes.

Not only are the Kdenlive team providing the usual packages for different Linux flavours (Ubuntu, Debian, Gentoo, Mandriva, OpenSUSE), they’re making it very easy for a wider range of users to try the software. The following downloads are also available:

We’re not aware of any other FOSS non-linear video editing tool that makes it so easy for new users to test and try the software.

BBC R&DTV Episode 2 Released

June 20, 2009 Leave a comment

We’re only about two weeks late noticing that the BBC has released the second episode in their R&DTV series. Again they’re providing a whole bunch of different video codecs – including Ogg Theora, but they’re still not their offering files encoded in their own Dirac codec. More information available on the main page or the BBC Backstage blog, but a wider selection of files can also be found directly on the FTP site where both 30 minute and 5 minute versions are available, as well as an entire asset bundle with rushes.

This episode features interviews with David Kirby on the BBC’s Ingex project, Matt Biddulph CTO of Dopplr and Jason Calacanis CEO of Mahalo.com.

The BBC has released this content under a Creative Commons attribution licence, allowing everyone to remix as they see fit, providing an original BBC credit is maintained.

Our post regarding Episode 1 of R&DTV goes into some more details regarding the technical details of the available files.

Interview with Edward Hervey about the PiTiVI video editor

May 13, 2009 Leave a comment

If you don’t already know, PiTiVI is an open source non-linear video editor. It’s still in the relatively early stages of development, with quite limited functionality compared to some of the well known commercial tools, used in production environments. PiTiVI is written in Python and uses the Gstreamer framework to do the back-end heavy lifting. While PiTiVI still has a long way to go, the last 12 months has seen some good advances and dedicated resources being assigned to the team by Collabora Multimedia.

Here’s an interesting interview with lead developer Edward Hervey, talking about the past, present and future plans for PiTiVI.

I’ve tried to use PiTiVI in the past, but unfortunately found it too limited for my editing needs. Subsequently I switched to Blender, which while predominantly a 3D authoring tool, does include a reasonably powerful video sequence editor. The learning curve for Blender is quite steep, so it’s not for everyone. Let’s hope a tool like PiTiVI can emerge to make open source video editing much easier and accessible for everyone.

Irony at NAB

May 8, 2009 Leave a comment

A couple of weeks ago I attended the yearly National Association of Broadcasters (NAB) trade show in Las Vegas. This year the show itself was a little quieter than usual – for example the RED camera circus wasn’t in town, drawing hundreds, blocking aisles and making a nuisance of itself – which generally meant it was easier to walk around, talk to people and actually learn a few things.

There wasn’t a lot of Open Source video products around that I could see. At least no one was openly touting their Open Source credentials. Smartjog were there, and they use FFmpeg as the back end transcoding solution in their servers.
However, I was highly amused by the irony of Microsoft, demonstrating new Silverlight 3.0 features, and using Big Buck Bunny as the demonstration footage. Could they not afford to license footage from elsewhere for their big screens? A small dose of irony in my day.
Big Buck Bunny and Silverlight

Kdenlive 0.7.3 Released

April 18, 2009 Leave a comment

April 15th saw the latest release of increasingly popular Linux Non-Linear Video editing software, Kdenlive. Now at version 0.7.3, this video editor seems to be one of the few in the Linux arena making regular progress and updates.

Occasionally a new PiTiVi blog post if made about future plans or minor improvements. Open Movie Editor has been very quiet for many months. It feels like Kdenlive and Blendor are the only two Linux video editors still making solid advances.

Anyway, Kdenlive 0.7.3’s major new features are as follows:

  • Clip grouping
  • Creation of rendering scripts for delayed rendering
  • Double pass encoding for rendering (just add “pass=2″ to your profile)
  • Track locking
  • Configurable monitor background color for better previewing
  • Web updates: you can now download new rendering profiles from Kdenlive’s web site
  • Split audio, allows you to separate a clip in it’s audio and video parts
  • Improved compatibility with Kdenlive 0.5 project files

Read more of the Release Notes on the Kdenlive website.

Kdenlive is starting to increasingly look like the Linux NLE of choice, for those who don’t have the time or inclination to figure out Blender’s complex User Interface.

BBC R&DTV – Creative Commons Tech TV

April 18, 2009 1 comment

In an interesting, and to be applauded, move from the BBC, they are now releasing a technology based television programme under a Creative Commons non-commercial attribution licence. R&DTV’s first episode is now available for free download in a number of file formats. There is a full 30 minute version available, a shorter 5 minute highlight version, as well as a complete Asset Bundle, which includes rushes that may not have made it into the final programme versions.

The BBC’s RAD blog has a launch announcement about this, followed up by another post 24 hours later outlining some small fixes.

The programme is PAL 720×576. The aspect appears to be 14:9 anamorphic. The little person inside me who wants the greatest and the best all the time, wonders why the filming wasn’t done in HD, even HDV would do.

I thought the “formats” described on the R&DTV website were a bit vague. What does QuickTime format and Matroska format really mean? Sure, I know about QuickTime and Matroska containers, but this doesn’t say anything about the video and audio essence contained therein. The best way to find out about this is to download each video and let FFmpeg take a look.

QuickTime Format (461.3MB):

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from ‘RDTV_ep1_5mins.mov':
Duration: 00:05:59.08, start: 0.000000, bitrate: 10777 kb/s
Stream #0.0(eng): Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
Stream #0.1(eng): Video: h264, yuv420p, 720×576, 25 tbr, 25 tbn, 50 tbc

That’s H.264 video with PCM audio. Strange they didn’t use AAC audio in a QuickTime file. Looking at that 10Mbps bitrate though, I’m guessing perhaps the BBC is expecting people to use this version for editing. But then why use H.264, rather than something that’s I-Frame only like IMX50? There’s also an Uncompressed version and another QuickTime version, which we’ll come to later.
 
Matroska Format (28.4MB):

Input #0, matroska, from ‘RDTV_ep1_5mins.mkv':
Duration: 00:05:59.04, start: 0.000000, bitrate: N/A
Stream #0.0(eng): Video: mpeg4, yuv420p, 720×576 [PAR 1:1 DAR 5:4], 25 tbr, 1k tbn, 25 tbc
Stream #0.1(eng): Audio: aac, 48000 Hz, stereo, s16

Generic mpeg4 video this time (Xvid perhaps) and here’s our AAC audio!

MP4 Format (65.4MB):

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from ‘RDTV_ep1_5mins.mp4′:
Duration: 00:05:59.10, start: 0.000000, bitrate: 1526 kb/s
Stream #0.0(eng): Video: h264, yuv420p, 720×576 [PAR 1:1 DAR 5:4], 25 tbr, 48k tbn, 50 tbc
Stream #0.1(eng): Audio: aac, 48000 Hz, stereo, s16

H.264 video again and AAC audio again. When opening this file with Totem to view, the Comments section says “HandBrake 0.9.3 2008121800″. Nice to know the BBC is using Open Source software for at least some of their video transcoding.

AVI Format (63MB):

Input #0, avi, from ‘RDTV_ep1_5mins.avi':
Duration: 00:05:59.04, start: 0.000000, bitrate: 1470 kb/s
Stream #0.0: Video: mpeg4, yuv420p, 720×576 [PAR 1:1 DAR 5:4], 25 tbr, 25 tbn, 25 tbc
Stream #0.1: Audio: mp3, 48000 Hz, stereo, s16, 160 kb/s

Generic mpeg4 video again, but this time with mp3 audio.

FLV Format (37.4MB)

Input #0, flv, from ‘RDTV_ep1_5mins.flv':
Duration: 00:05:59.07, start: 0.000000, bitrate: 844 kb/s
Stream #0.0: Video: vp6f, yuv420p, 1024×576, 716 kb/s, 25 tbr, 1k tbn, 1k tbc
Stream #0.1: Audio: mp3, 44100 Hz, stereo, s16, 128 kb/s

VP6 for the video codec and mp3 for the audio. No surprises there then. The bitrate is quite low though for VP6 content, quality will suffer.

Ogg Format:

Input #0, ogg, from ‘RDTV_ep1_5mins.ogg':
Duration: 00:05:59.08, start: 0.000000, bitrate: 683 kb/s
Stream #0.0: Video: theora, yuv420p, 720×576, PAR 1:1 DAR 5:4, 25 tbr, 25 tbn, 25 tbc
Stream #0.1: Audio: vorbis, 48000 Hz, 5.1, s16, 516 kb/s

Theora for the video and vorbis for the audio, again no surprises there. 5.1 audio is a nice touch though. However, again, the bitrate is very low. Why would the BBC do this? The MP4 version, with H.264 video at a higher bitrate, is going to look far superior.

QuickTime 2 Format (155MB):

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from ‘RDTV_ep1_5mins_2.mov':
Duration: 00:05:59.08, start: 0.000000, bitrate: 3627 kb/s
Stream #0.0(eng): Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
Stream #0.1(eng): Video: h264, yuv420p, 720×576, 25 tbr, 25 tbn, 50 tbc

H.264 video and PCM audio. This second QuickTime file is found only on the FTP site and not linked to directly from the main page. The bitrate is much lower than the previous QuickTime file.

QuickTime Uncompressed Format (7GB):

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from ‘RDTV_ep1_5mins_uncompressed.mov':
Duration: 00:05:59.08, start: 0.000000, bitrate: 167428 kb/s
Stream #0.0(eng): Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
Stream #0.1(eng): Video: rawvideo, uyvy422, 720×576, 25 tbr, 25 tbn, 25 tbc

There we go, raw video in the 4:2:2 colour space at 165Mbps, with PCM audio again. I wonder whether the content was filmed at anywhere near this resolution. Given that the programme is only SD, I’m guessing that the highest quality recording would have been done direct to Digital Betacam, which is only the equivalent of 90Mbps, unless of course the whole thing was done tapeless, which I must admit to doubting.

One last puzzlement is why a Dirac version wasn’t supplied, given that this is the BBC’s own R&D developed codec.
 

Categories: FFmpeg, Video Tags: , , , ,

Interview with FFmpeg Developers

March 11, 2009 Leave a comment

Two posts in two days after such a long silence, who’d have thought it…… And again it’s about FFmpeg.

This time Phoronix has posted an interesting interview summary with Diego Biurrun,
Baptiste Coudurier, and Robert Swain, three of the many, but very key, developers working on the FFmpeg project. The interview covers some interesting topics about the future of FFmpeg, the difficulties of maintaining such a large project, managing developer motivation for writing codecs and the limited corporate sponsorship the project has so far received.

I’ve known Baptiste for a year or so, having met at the National Association of Broadcasters (NAB) convention in Las Vegas in April 2008. I’d like to personally thank him for the work he has done on implementing DNxHD in FFmpeg.

Anyway, read the interview and learn something about behind the scenes at FFmpeg.

Also worth a read, which I just found today, is the Phoronix tests on NVIDIAs VDPAU drivers on a cheap chipset and graphics card.

FFmpeg Makes an Official Release!

March 10, 2009 Leave a comment

It’s been a long while since I’ve posted on this blog, but finally today something has spurned me into action. 

The FFmpeg team have finally made a release – version 0.5 – with a silly long name. Previously, users were always told to download and compile the latest SVN version of FFmpeg, if they expected any support from the mailing lists.
Now it would seem that there is a stable release, only a few years since the last one, that can be used by software developers and packagers everywhere. I still expect that many mailing list issues will be dealt with by the instruction to download from the SVN or Git repository and compile. I also expect that bug fixes and enhancements will make it into SVN quite quickly, but that also the next release might be some time away.
Release notes are available on the FFmpeg changelog (long!) and there’s a lively, as always, Slashdot discussion around this momentous event.

New Version of PiTiVi – 0.11.2

October 30, 2008 Leave a comment

The news is a couple of weeks old now, but I thought PiTiVi was dead and wasn’t bothered visiting their website for updates anymore. The link to their Forum still goes to a default Apache page.

Anyway, GStreamer and Python based video editor, PiTiVi, released version 0.11.2 on October 15th, after almost a year of project silence. It’s good to know progress is still being made.
The 0.11.2 release is not yet meant to be production ready, but does include a number of updates and bug fixes. Full details as always on the Release Notes page.
There also seems to be a reasonable amount of activity on the PiTiVi Wiki and mailing list. Not only that, various blog posts on the Gstreamer Planet feed indicate that Collabora Multimedia have hired a part-time programmer to work specifically in PiTiVi, and are looking for another head as well. The target is a April 2009 for a “usable release”.
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