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An Interview With the Developers of FFmpeg 80

An anonymous reader writes "Following the long-awaited release of FFmpeg 0.5, Phoronix has conducted an interview with three FFmpeg developers (Diego Biurrun, Baptiste Coudurier, and Robert Swain) about this project's recent release. In this interview they talk about moving to a 3/6-month release cycle, the criteria for version 1.0, Blu-Ray support on Linux, OpenCL and GPGPU acceleration, multi-threading FFmpeg, video APIs, their own video codecs, and legal challenges they have run into."
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An Interview With the Developers of FFmpeg

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  • Whither Google? (Score:3, Insightful)

    by negatonium ( 1103503 ) on Friday March 13, 2009 @12:56PM (#27182623)
    They say they have trouble implementing code due to time and motivational constraints. Seems to me that if Google/YouTube has built a very successful website around the FFmpeg engine then Google ought to pony up some programming help with improving the project. Wouldn't that be "The right thing to do" (TM)?
  • Anyone know what kind of performance increase VDPAU can give compared with software decoding?

    That application I'm working on needs to decode lots of H.264 streams so being able to offload that to a GPU would be a godsend.

    • Re: (Score:2, Interesting)

      by nerdguy0 ( 101358 )
      Take a look at this article [] linked to in TFA. Seems like a pretty big boost.
    • Re:VDPAU sounds cool (Score:5, Interesting)

      by limaxray ( 1292094 ) on Friday March 13, 2009 @01:52PM (#27183467)
      It works VERY well. Decoding a 1080p H.264 video using software on my dual-core 3GHz machine pegs the cores back and forth to around 80-90%, but plays fairly well. Using an mplayer build patched to support VDPAU, my CPU remains idle (clock drops to 1GHz, and 1-3% CPU usage) and plays equally as well, if not better. Furthermore, I was still able to go about my business with no noticeable impact on performance, even when using hardware-dependent Compiz. I have not though, tried this on multiple streams.

      Oh, and this is using some cheap NVidia 8600 something-or-other card that I picked up new for ~$50. I, for one, was truly impressed by VDPAU and what it means for low-cost HD content.
    • Pretty good, you can easily decode 1080p H264 video with a cheap nvidia card. It is also consume less power and cooler than using CPU for decoding, so VDPAU = great for HD video on laptop.

      I also find it interesting that VDPAU can help decoding H264 video that I can't decode using its counterpart on Windows (DxVA) :)

  • by Anonymous Coward on Friday March 13, 2009 @01:46PM (#27183379)

    hall of shame []

    • The first I randomly clicked on that list (Orb) has apparently complied with the license. It just hasn't been verified that the source they provide compiles. Isn't it a bit over the top to include projects like that in a Hall of Shame?
    • by Twinbee ( 767046 )

      Paradoxically, it could be doing those sites a favour, as there isn't a 'nofollow' in the links, so all the PR is passed on.

    • by trawg ( 308495 )

      Heh, interestingly AVS Video Converter is in there - I've seen that advertised on Slashdot a bunch lately

  • ffmpeg is a godsend to the FOSS community. Great work to the ffmpeg developers and I know I speak for a lot of people when I say that I'm looking forward to the fruits of their hard work.
  • has posted some project ideas [] for Google Summer of Code projects, including "VDPAU state tracker for Gallium. Admit it, it would be pretty cool."

  • Legal Issues? (Score:5, Interesting)

    by Paul Slocum ( 598127 ) on Friday March 13, 2009 @04:11PM (#27185503) Homepage Journal
    In the "Legal Issues" section of the article, I expected to see something about the issue of FFMPEG potentially infringing on existing patents. Instead there's just some stuff about violating the GPL. Seems like a major oversight to me.

    What *is* up with the patent issue? Is it possible to use FFMPEG legally in commercial software if you adhere to the GPL and buy licenses for the patents that you're using? Since I already paid for software that includes encoders for some of these patented codecs, does that allow me to legally use FFMPEG? In my lifetime, how many times do I have to pay the patent fees for MPEG2 encoding?
    • Re: (Score:2, Informative)

      by Anonymous Coward

      The "official" answers to that are here:
      And no, I don't think you will find them useful, a lawyer is the right place to get legal advice.

    • Re: (Score:3, Informative)

      by LackThereof ( 916566 )

      From the FFMPEG website:

      Patent Mini-FAQ

      A lot of legal questions surrounding patents arise when discussing multimedia technology. This mini-FAQ attempts to address these issues. Note that much of this discussion is based on precedent, or what has happened in the past under similar circumstances. Very little consideration is given to what could happen. If you use your imagination, you can visualize any dire scenario and cease doing any productive work.

      Q: Does FFmpeg use patented algorithms?
      A: We do not know, we are not lawyers so we are not qualified to answer this. Also we have never read patents to implement any part of FFmpeg, so even if we were qualified we could not answer it as we do not know what is patented. Furthermore the sheer number of software patents makes it impossible to read them all so no one (lawyer or not) could answer such a question with a definite no, those who do lie. What we do know is that various standards FFmpeg supports contain vague hints that any conforming implementation might be subject to some patent rights in some jurisdictions, examples for such statements are:
      For H.264:

      ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process.

      And for MPEG-4:

      The user's attention is called to the possibility that, for some of the processes specified in this part of ISO/IEC 14496, conformance with this specification may require use of an invention covered by patent rights. By publication of this part of ISO/IEC 14496, no position is taken with respect to the validity of this claim or of any patent rights in connection therewith.

      Q: Is it legal to use such patented algorithms?
      A: Patent laws change wildly between jurisdictions. Besides, even in places where software patents are recognized, there is serious doubt about the legitimacy of such legislation. Note that patents on algorithms are illegal in many countries. Plus the use of patents to prevent the usage of a format or codec on a specific operating system or together with specific other software might violate antitrust laws.

      Q: Bottom line: Should I be worried about patent issues if I use FFmpeg?
      A: Are you a private user working with FFmpeg for your own personal purposes? If so, there is remarkably little reason to be concerned. Are you using FFmpeg in a commercial software product? Read on to the next question...

      Q: Since FFmpeg is licensed under the LGPL, is it perfectly alright to incorporate the whole FFmpeg core into my own commercial product?
      A: You might have a problem here. Sure, the LGPL allows you to incorporate the code. However, there have been cases where companies have used FFmpeg in their projects, usually for such capabilities as superior MPEG-4 decoding. These companies found out that once you start trying to make money from certain technologies, the alleged owners of the technologies will come after their protection money. Most notably, MPEG-LA (licensing authority) is vigilant and diligent about collecting for MPEG-related technologies.

      Q: You called the patent license fee protection money, is this a joke?
      A: No. The legal validity of these patents is highly questionable. Still in many current legal systems it is very easy to ruin a company with patents even if the patents are invalid. Paying the (small) license fee is much cheaper than a patent lawsuit during which you would not be able to sell your product as the patent would be valid until you win the lawsuit 5+ years in the future. That is assuming you did not go bankrupt in the meantime...

      Q: Can I be safe if I have paid my protection money.
      A: You can never be safe as long as your country recognizes software patents as valid. There are companies that own many patents, pay and cross-license for other companies patents, but even such companies are being found guilty of infringing some obscure little-known patent and end up paying millions for it. That's why lobbying against software patents is in your own interest. Of course none of this is related to you using FFmpeg or another codec implementation. If you want to be safe the only option is not to touch any software at all.

      • There is this new thing on the internet, called "hyperlinks", so you don't have to copy content around anymore.
        Now I could link to a introduction, but that would probably confuse you. So:

        <<< imagine content of here >>>

    • Re: (Score:3, Interesting)

      by HTH NE1 ( 675604 )

      In the "Legal Issues" section of the article, I expected to see something about the issue of FFMPEG potentially infringing on existing patents. Instead there's just some stuff about violating the GPL. Seems like a major oversight to me.

      So that's not why I can't get ffmpeg to strip the "Copy once" broadcast flag out of my HD recording of 24 "Day 7: 6:00 PM - 8:00 PM"?

      I can hear all the audio, but I can't see anything other than the cable-inserted ads. VLC will play it but not transcode it. MPEG Streamclip will rip the audio but not the video. Mencode with copy and copy fails. Mplayer saving to tga files works but takes up too much disk space and QuickTime Player doesn't offer converting an image sequence to video at 59.97 fps.

      I just want t

      • by iMacGuy ( 199233 )
        ffmpeg has no idea what a broadcast flag is; your file is probably encrypted, which it won't deal with.
        • Re: (Score:3, Interesting)

          by HTH NE1 ( 675604 )

          If it were encrypted, VLC and MPlayer would not be able to play it, but they can and do.

          But ffmpeg not knowing about the flag would explain why it wouldn't strip what it didn't know about. Not sure why Mencoder would choke with an audio complaint trying to do the same thing.

          Hasn't anyone created a filter that just clears the broadcast flag from a recorded transport stream? If I had that then MPEG Streamclip would handle everything else for me.

  • To anyone involved in maintaining ports of third-party software to a particular OS (or even a distro), working with a release of that software is quite important. Unfortunately, ffmpeg-developers couldn't be bothered with such things. Here is a rather arrogant response [] I got two years ago from them:

    We have them [releases -mi]. They are called nightly snapshots. Now, if you were to ask us to spend our time on evaluating and telling you which of the snapshots we consider to be more stable than the other ones

    • Wow. Just wow. So, you're all pissy because although they're giving you something amazing for free, they're not also giving you extra stuff that you want but they're not interested in. Do you also insult people at christmas when they don't give you exactly the presents you want?

      • by mi ( 197448 )

        So, you're all pissy because although they're giving you something amazing for free [...]

        Having been contributing to Open Source for over a decade myself, I'm long past your stage. It is only "free" if your own time is worthless. Mine is not. If I spend hours porting ffmpeg-2008FOO to FreeBSD to make, say, mplayer work well and then realize, that I must repeat most of that porting effort to make cinerella (which comes with its own, slightly different ffmpeg-2008BAR) build correctly, I will wonder, why the h

  • I have some notes on my efforts to compile ffmpeg with all available codecs (using PLF repositories) for Mandriva 2009.0 on my blog, []. Comments appreciated.
    • Re: (Score:2, Informative)

      by Anonymous Coward

      -O3 and -funroll-loops are likely to increase code size, and thus increase cache pressure. Particularly for H.264 this in our limited experience is more likely to slow things down that speed them up. Generally it is a bad idea to "speed-optimize" without benchmarking.

The absent ones are always at fault.