FFmpeg Announces High-Performance VP8 Decoder

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FFmpeg Announces High-Performance VP8 Decoder

Posted by Soulskill on Saturday July 24, 2010 @01:16AM from the harder-better-faster-stronger dept.

An anonymous reader writes "Three FFmpeg developers — Ronald Bultje, David Conrad, and x264 developer Jason Garrett-Glaser — have written the first independent, free implementation of a VP8 video decoder. Benchmarks show that it's as much as 65% faster than Google's official libvpx. The announcement also gives a taste of what went into the development process, as well as the optimization techniques used. Currently it's only fully optimized on x86, but ARM and PowerPC optimizations are next in line for development."

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Spec' Writing Course by Manip · 2010-07-24 01:23 · Score: 5, Interesting

As someone who spends most of their work day implementing someone else's specifications I know exactly where they are coming from. I honestly cannot tell if people are bad at writing spec's because they're simply lazy or if they need to be trained to document their file formats completely.
When I think back to my University days we never really learned how to write a specification and wonder if that wouldn't be a course worth teaching. Perhaps you get the students to write a program that outputs a set of complex information into a format, and then get them to write an end to end specification to both read and write that format.
My favourite moments are when you realise that the current implementation not only doesn't follow the spec' but directly contracts it (e.g. A "bool" that can be TRUE, FALSE, "", "null", or "nan").
1. Re:Spec' Writing Course by Anonymous Coward · 2010-07-24 01:47 · Score: 1, Informative
  
  e.g. A "bool" that can be TRUE, FALSE, "", "null", or "nan"
  Well since TRUE and FALSE are uppercase (meaning preprocessor definitions/value constants) it's obvious that "bool" was not meant to be a unique type in this hypothetical language, and instead was a typedef for an integer type. Nothing a coding standard can't rectify.
2. Re:Spec' Writing Course by Nerdfest · 2010-07-24 02:07 · Score: 1
  
  Where I went to school we actually did have a course in business writing that included writing specifications, proposal requests, etc. I didn't enjoy it at the time but it has come in useful on many occasions.
3. Re:Spec' Writing Course by daveime · 2010-07-24 02:44 · Score: 4, Funny
  
  Come one, everyone knows that a boolean can have the values TRUE, FALSE and FILE_NOT_FOUND.
4. Re:Spec' Writing Course by sdiz · 2010-07-24 02:52 · Score: 2, Insightful
  
  "specifications" in business writing class is not technical specification.
  You don't describe how you convert colorspace, inverts the matrix, etc in them
5. Re:Spec' Writing Course by daemonc · 2010-07-24 04:36 · Score: 1
  
  When I think back to my University days we never really learned how to write a specification and wonder if that wouldn't be a course worth teaching.
  
  At WVU we had Software Engineering, which was pretty much entirely about writing specs, and is required for all CS majors.
  Most people think we're just a party school (which, for the most part, is true), but the more I hear about other universities, the more I realize that our computer science and engineering programs are probably some of the best in the country.
  
  --
  All that we see or seem is but a dream within a dream.
6. Re:Spec' Writing Course by Anonymous Coward · 2010-07-24 05:22 · Score: 1, Funny
  
  "Oh, Fry, I love you more than the moon and the stars and the - POETIC IMAGE NUMBER 37 NOT FOUND."
7. Re:Spec' Writing Course by Anonymous Coward · 2010-07-24 06:12 · Score: 0
  
  When I think back to my University days we never really learned how to write a specification and wonder if that wouldn't be a course worth teaching.
  At WVU we had Software Engineering, which was pretty much entirely about writing specs, and is required for all CS majors.
  Most people think we're just a party school (which, for the most part, is true)
  hahahaha, it's funny because it's true
8. Re:Spec' Writing Course by badkarmadayaccount · 2010-07-28 01:48 · Score: 1
  
  s/FILE_NOT_FOUND/NULL
  <me action='self-whoosh' />
  
  --
  I know tobacco is bad for you, so I smoke weed with crack.
We need WebM by ciaran_o_riordan · 2010-07-24 01:35 · Score: 5, Informative
Abolishing software patents will take years. Most of the short-term goals are a waste of time, or a distraction by companies that don't really want to end the problem, but WebM is a project that would have a big impact, and has a good chance of succeeding. Great to hear that Xiph continues to support it!
File formats and compatibility are the biggest problem caused by software patents. They're how monopolies get too powerful, and they're how companies with people-friendly terms get locked out of commercial software development. (Commerce isn't the only valid form of software development, but it's important for the sustainability of a project.)
--
Expert in software patents or patent law? Contribute to the ESP wiki!
1. Re:We need WebM by ccr · 2010-07-24 06:29 · Score: 1
  
  Umm, excuse me, but FFmpeg project has nothing to do with Xiph.
So what should I do with my DVD collection? by Anonymous Coward · 2010-07-24 01:35 · Score: 2, Interesting

I usually rip my DVDs to ~1.2GiB Xvid avi files at native res using mencoder (not reencoding the audio), and have been doing this for many years. Does anyone know what combination of muxer and audio/video codecs is preferred nowadays? I'm thinking of using Matroska with Vorbis for audio but I'm completely lost as to what video codec to use. As for which tools to use, I find most of what I need in the Debian repositories but I'm open to suggestions.
Also, I prefer quality over size but over 1.2GiB for a 90 minutes DVD is too much IMHO.
1. Re:So what should I do with my DVD collection? by shaitand · 2010-07-24 02:18 · Score: 1
  
  x264 in avi container is the most popular. x264 is going to take a little better than double the cpu to playback. The quality is better xvid even for dvd source but not dramatically better. It is substantially better for HD rips.
  If you use a weaker cpu for playback you are going to want to stick to xvid. And if you are concerned about 1.2GB of disc space when 1TB HDD are less than $100 you probably are.
  "I'm thinking of using Matroska with Vorbis for audio but I'm completely lost as to what video codec to use."
  So you currently use full source quality audio but you are thinking about crunching it down and calling it an upgrade? Its your call, but you can kill the audio with your xvid avi's too.
2. Re:So what should I do with my DVD collection? by TheRaven64 · 2010-07-24 02:21 · Score: 2, Insightful
  
  Also, I prefer quality over size but over 1.2GiB for a 90 minutes DVD is too much IMHO.
  Really? It's still a factor of 5-10 improvement over the DVD...
  When I got my first DVD drive, it went in a computer with a 20GB hard disk. For about half what I paid for that disk now (less when you factor in inflation), I can buy a 1.5TB disk. Most DVDs aren't full, they only use 6-8GB of space, so that's enough for 200 DVDs. At that price, why bother messing around with transcoders and recreating the menus - just store them as disk images and then you can transcode them later if you want.
  
  --
  I am TheRaven on Soylent News
3. Re:So what should I do with my DVD collection? by Anonymous Coward · 2010-07-24 02:28 · Score: 1, Informative
  
  use x264 to encode video to h.264, audio can be anything you like if you mux into matroska. If you care about quality then forget about using xvid. OK, it seemed great several years ago, but next to video encoded with x264 it is *pitifully* bad. You can use ffmpeg or mencoder to handle the cropping, scaling, muxing, encoding parameters etc. ffmpeg is better in some ways because it can mux successfully into mkv or mp4 while mencoder is only really useful for avi or outputting raw video.
  If a movie looks good at 1.2GB made with xvid, it will usually look equally good at 700MB in h.264. The same movie at 1.2GB in h.264 will be so much better you'll wonder why you ever though xvid doesn't look like shit.
  x264 encoding initially seems horribly complex, but google for x264 presets and ffmpeg x264 presets and read the docs that come with ffmpeg and x264 and you'll soon be producing rips that look indistinguishable from the source DVD or VOB *and* are smaller than your xvid avi files.
4. Re:So what should I do with my DVD collection? by Anonymous Coward · 2010-07-24 02:46 · Score: 1, Informative
  
  Personally, I've been going with H.264 and native audio (either AAC or DTS), in an MKV file. I usually throw the subtitles, and any director commentary (downmixed MP3 96kbps stereo 44.1) tracks.
  I've been doing the same with my blu-ray rips, but get frustrated because handbrake and VLC can't handle the subtitles on-disk.
5. Re:So what should I do with my DVD collection? by Anonymous Coward · 2010-07-24 02:55 · Score: 1, Insightful
  
  Using a modern audio codec like Vorbis is hardly "killing" the audio. Vorbis is generally transparent at around q3 and still quite respectable below that, and can thus offer savings ranging from "pretty good" (~1/2 with 192kbps AC-3) to "very significant" (~1/16 with raw PCM).
  Also, H.264 in AVI is an abomination, like sex with other men or eating shrimp. If you really want to risk eternal suffering in the fiery depths of encoding hell, go right ahead, but don't say I didn't warn you.
6. Re:So what should I do with my DVD collection? by fandingo · 2010-07-24 03:01 · Score: 3, Interesting
  
  That's sort of what I do, but I would like to watch my DVDs on a dedicated device, which doesn't support ISOs.
  I have a 3TB RAID array that I'm just beginning to populate. I rip the full ISO, and then rip the videos (usually TV episodes) into h.264+aac in mp4. I used to use mkv, but it doesn't have good device support. I use a UPnP server on my Linux box to share with my PS3, which works great. Also, mp4 (really m4v) is great for iDevices as well, so I have that flexibility if I want.
  I encode with handbrake, which is ok, although I'm not happy with the Linux support. Since it's so Mac-centric, there isn't any support for the most recent release of Gnome (so no distros released after March 2010 work), so I have to run a dev version. I want really high quality encodes. I get pretty much perfect quality from the encodes and they run about 600-800MB/hr for film; animation is all over the place, but quality is good: 280-600MB/hr.
  I don't plan to delete the ISOs until my disk space is full. This way if technology changes, then I can still encode from source rather than from another encode.
  That being said, I think that h.264 will be around for many years.
7. Re:So what should I do with my DVD collection? by imroy · 2010-07-24 03:08 · Score: 1
  Here's what I use:
  
  MPEG-4 AVC video (a.k.a "h.264")
  MPEG-4 AAC audio
  MPEG-4 container
  Notice a pattern there?
  For Debian users, add the debian-multimedia repository and install x264, faac, and gpac (for the MP4Box tool).
8. Re:So what should I do with my DVD collection? by shaitand · 2010-07-24 03:09 · Score: 1
  
  "Using a modern audio codec like Vorbis is hardly "killing" the audio"
  It is compared with using the source multi-channel audio.
9. Re:So what should I do with my DVD collection? by Anonymous Coward · 2010-07-24 03:13 · Score: 0
  
  AAC for audio blows away everything else. There is no point in even discussing anything else. AAC is the most modern and best performing audio encoding out there.
  Matroska is a good choice because it's easy to convert to any other container type as needed.
  As others mentioned, H.264 (eg. x264 encoder) is the way to go these days. Hardware support is getting better and it's the future (most commercial digital sources these days use H.264 or a variation).
  I encode everything using Matroska, H.264 (x264) at 1200 kbps (2-pass), with AAC Dolby Pro Logic II surround (the best compromise between space usage and still having surround-sound). This results in ~1GB or so per 90 minutes but varies depending on the actual length. Superb quality there.
10. Re:So what should I do with my DVD collection? by smallfries · 2010-07-24 03:36 · Score: 1
  
  Not only does this make sense, but sometimes later never comes.
  I rip DVDs straight to a drive array as plain isos. The original plan was to get around to re-encoding the video as h264 when the drives were full / I could be bothered. I don't buy new drives very often but the drive array is still growing faster than it is filling.
  The next hike is 2GB drives to replace some of the oldest in the array now that they are down to 100 quid. As this is prompted by errors starting to show up on an old drive rather than a need for space it seems possible that cheap storage has exceeded my needs for storage space.
  
  --
  Slashdot: where don knuth is an idiot because he cant grasp the awesome power of php
11. Re:So what should I do with my DVD collection? by Anonymous Coward · 2010-07-24 03:52 · Score: 0
  
  AAC for audio blows away everything else. There is no point in even discussing anything else. AAC is the most modern and best performing audio encoding out there.
  Nice troll...
  Are seriously trying to imply that AAC doesn't have a worse quality/compression ratio than Vorbis? Yes, it does has nice features and strengths over Vorbis, but performance is not one of them.
12. Re:So what should I do with my DVD collection? by Anonymous Coward · 2010-07-24 04:03 · Score: 0
  
  It certainly is killing the audio. DVDs tend to have 5.1 sound, AC3 at 640kbps or DTS at 1500kbps. Why would you want to destroy that into a format that isn't supported by 99+% of the HT hardware?
13. Re:So what should I do with my DVD collection? by Anonymous Coward · 2010-07-24 04:30 · Score: 0
  
  DVDs tend to have 5.1 sound
  Which Vorbis can do. That's if he needs that at all, which hasn't been stated anywhere.
  
  AC3 at 640kbps or DTS at 1500kbps
  More bits doesn't mean more better.
  
  Why would you want to destroy that into a format that isn't supported by 99+% of the HT hardware?
  The fact that the OP himself said he is considering Vorbis certainly suggests he isn't going to be using something that doesn't support it. And you still haven't made a credible argument as to how it's "destroying" anything.
14. Re:So what should I do with my DVD collection? by cheesybagel · 2010-07-24 04:39 · Score: 1
  
  IMO AAC is about the same quality as Vorbis. Matroska is indeed much superior to the MPEG-4 container. H.264 is still the best video codec standard (haven't seen any WebM videos yet).
  It was good that Google did this. Theora is better than H.263, but was much inferior to H.264. I suspect as WebM implementations gets more work we will see a codec with similar quality to H.264.
  IMO there are good free sound codecs across the spectrum: vorbis for compressed music, flac for uncompressed music, speex for sound, etc. It's video that has been the issue.
15. Re:So what should I do with my DVD collection? by Bert64 · 2010-07-24 05:28 · Score: 1
  
  But if you have 5.1 vorbis, how do you play it back?
  I have optical cables to my receiver, when playing a dvd the raw ac3 sound is sent over this cable to the received and decoded there... I don't think it has the capability to send 5.1 channels of raw pcm audio over this link, so the only way to get it to the receiver is to either encode it back to ac3 or use the 8 individual analog channel inputs on the receiver which would get extremely messy with long cables...
  
  --
  http://spamdecoy.net - free throwaway anonymous email - avoid spam!
16. Re:So what should I do with my DVD collection? by willy_me · 2010-07-24 05:44 · Score: 1
  
  At that price, why bother messing around with transcoders and recreating the menus
  Well, I for one would rather the menus not be there. If I want them I'll use the physical DVD. The other reason for transcoding is to reduce the file size so that it streams over wireless. Those little media players are cheap and work great - but often people do not have a CAT5 cable going to their TV. And while wireless might be fast enough most of the time, a little interference and you will notice the player start to stutter. Lower bandwidth requirements result in more reliable streaming.
17. Re:So what should I do with my DVD collection? by Anonymous Coward · 2010-07-24 05:58 · Score: 0
  
  I've used RipBot for HD-DVD rips and it works very well. Should be similar for Blu-Ray. Handles subtitles, but doesn't seem to support multiple audio tracks.
18. Re:So what should I do with my DVD collection? by ObsessiveMathsFreak · 2010-07-24 10:13 · Score: 1
  
  I usually rip my DVDs to ~1.2GiB Xvid avi files at native res using mencoder (not reencoding the audio), and have been doing this for many years. Does anyone know what combination of muxer and audio/video codecs is preferred nowadays?
  
  Speaking for myself, I use XviD for video, raw ac3 or perhaps ogg for audio and mux everything together in an mkv file for best results.
  The big question I've faced is whether to use h264 or not for video. After considering this for a long time, I finally came to the conclusion that for personal videos on your own hard drive, XviD is probably a better option. There are two reasons for this.
  Firstly, when it comes to personal videos I tend to encode at a high bitrate (>1200 kbits/s). I can spare the hard drive space for this and the codec usually does very well. Indeed at such high bitrates, while h264 probably still does a better job, it's own inherent artefact (usually in the form of a slight "blur", can allow subjective argument about which codec is doing a better job. Basically, at bitrates like these, you're far more into subjective than objective territory.
  The second reason is probably more important. One of the huge disadvantages of h264 is its encode times. A 90 minute DVD movie can take up to five hours to encode, whereas the equivalent XviD may take less than one. Given that you may only watch this film three or four times over the rest of your life, you have to question why the encoding process should be longer than the films expected use time.
  Clearly, this logic runs entirely contrary to those that someone encoding for web distribution would have. But since h264 has largely been developed for mass/web distribution anyway, I don't think this is surprising. If this VP8 codec performs well and speedily at higher bitrates, I might change my current setup; but for now, I would recommend sticking to XviD for home DVD->Hard Drive encoding.
  
  --
  May the Maths Be with you!
19. Re:So what should I do with my DVD collection? by cynyr · 2010-07-24 11:45 · Score: 1
  
  analog out a high end sound card, into some single channel amps into some nice speakers.
  
  --
  All of the above was encrypted with a Quad ROT-13 method. Unauthorized decryption is in violation of the DMCA.
20. Re:So what should I do with my DVD collection? by h7 · 2010-07-25 19:01 · Score: 0
  
  It's not just the most of one 1TB drive, but the continuous problem with keeping one running out of space. Though I have the bandwidth, I keep DVD quality backups. Even then, my over 3TB space is running low, not to mention the hassle of interchanging external hard drives.
21. Re:So what should I do with my DVD collection? by h7 · 2010-07-25 19:06 · Score: 0
  
  I think the best option while ripping is do the highest resolution and file format that your mobile device uses. E.g. in my case ipod touch 2G supports 640*480, and x264 which is what I use. That is good enough of casual viewing on a TV or computer as well.
22. Re:So what should I do with my DVD collection? by ttsiod · 2010-07-25 21:58 · Score: 1
  
  Which UPnP server SW did you use under your Linux?
any dvd professional by Anonymous Coward · 2010-07-24 01:53 · Score: 0

ill rip my dvds to x264 that are a bit smaller and better quality then your xvids
if vp8 can give me as good a quality viewing in less space it wins
OTHER WISE
im not moving anywhere
1. Re:any dvd professional by shaitand · 2010-07-24 02:11 · Score: 2, Informative
  
  "ill rip my dvds to x264 that are a bit smaller and better quality then your xvids"
  True enough. Not automatically preferable though because they require more than double the cpu to decode.
  "if vp8 can give me as good a quality viewing in less space it wins"
  Probably not. x264 has a number of innate visual advantages to compressing video that were previously mpeg compressed. VP8 generally seems to win on raw uncompressed video in the races I've seen.
  As for cpu, it does count, especially if you are streaming to a set top box or old pc for playback). I don't know what kind of cpu power is required to play back VP8.
2. Re:any dvd professional by drinkypoo · 2010-07-24 02:21 · Score: 2, Insightful
  
  Probably not. x264 has a number of innate visual advantages to compressing video that were previously mpeg compressed. VP8 generally seems to win on raw uncompressed video in the races I've seen.
  And the problem is, where do you find raw, uncompressed video? About the only place you will find it is if you are transferring an analog source to a dedicated internal capture card. Virtually everything else uses some form of MPEG or H.264 compression.
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
3. Re:any dvd professional by Anonymous Coward · 2010-07-24 02:28 · Score: 4, Informative
  
  > Probably not. x264 has a number of innate visual advantages to compressing video that were previously mpeg compressed. VP8 generally seems to win on raw uncompressed video in the races I've seen.
  You are right and wrong at the same time. x264 has many psycho-visual optimizations (these lower PSNR) that make it look better, while VP8 is optimized for PSNR, which doesn't necessarily look good. If you compare x264 in baseline profile (not what you'd use for a DVD rip) and VP8 at best settings, VP8 might beat x264 at PSNR, but it'll still look worse.
  Now, for recompression: This is basically misinformation, based on a comment made by the VP8 devs in the MSU test, where VP8 did relatively better on the only uncompressed source. Of course this source (moving calendar) also has very peculiar properties with regards to motion compensation, which is more likely the reason for different performance. MPEG compressed content doesn't actually bias against VP8 more than against H.264, since VP8's block transform is actually more similar to MPEG2's than that of H.264.
  Long story short: Until VP8 gets psycho-visual optimizations, it'll always look worse than x264 at the same bitrate. Once it does get them, it might be possible for VP8 to reach x264 quality in baseline profile. Baseline is only used for phones and the like, though.
4. Re:any dvd professional by Anonymous Coward · 2010-07-24 02:37 · Score: 0
  
  Oops, forgot to reply to this one:
  > As for cpu, it does count, especially if you are streaming to a set top box or old pc for playback). I don't know what kind of cpu power is required to play back VP8.
  VP8 takes about the same amount of CPU power to decode as H.264. Before this decoder was created, it actually took way more!
5. Re:any dvd professional by PhrostyMcByte · 2010-07-24 02:52 · Score: 1
  
  Probably not. x264 has a number of innate visual advantages to compressing video that were previously mpeg compressed. VP8 generally seems to win on raw uncompressed video in the races I've seen.
  Then you've been fooled. The study you're referring to used videos pre-compressed with other MPEG standards, and the VP8 guys claimed that that biased it toward other MPEG-like codecs. They said VP8 got better with an uncompressed source.
  VP8 got better. On a single test. A single test is not conclusive for anything but that single test. Note that, even for that single test, it still didn't beat H.264 -- it merely got better.
  What we know (not assume), is that the core of VP8 is almost identical to the H.264 Baseline profile. VP8 is an MPEG-like codec! It's got a few small tweaks, some that help and some that don't. The features that would give it an obvious advantage or disadvantage on pre-compressed video are identical.
6. Re:any dvd professional by shaitand · 2010-07-24 02:54 · Score: 3, Insightful
  
  Agreed. The fact that VP8 generally does hold its own side by side with x264 is a pretty impressive testament to the codec.
  But who cares if VP8 is technically a better codec if it doesn't actually produce superior results with the source video we work with? If it cuts CPU for decoding while offering on par quality that would be a solid advantage.
7. Re:any dvd professional by drinkypoo · 2010-07-24 03:54 · Score: 5, Interesting
  
  If it produces adequate results, then I for one will use it simply because of the stance it takes with regards to patent encumbrance. To me that is perfectly sufficient, because I'm not trying to create any HD video... yet? I don't want to get into building disk farms. Anyway, I shouldn't have to worry about things like whether the camera that says pro on it has a professional H.264 license associated with it, or whether the video editing software whose name ends in pro has a professional H.264 license... but last I heard, there were rather high-profile examples of each indeed not having same. This is not something that I want to have to worry about. Indeed, I would say that an intellectual property law system which permits this to become something you have to worry about is broken as designed.
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
8. Re:any dvd professional by cynyr · 2010-07-24 04:23 · Score: 2, Informative
  
  I rip h.264(libx264 level 4.1 high profile), with ACC 5.1 and 2.0(muxed properly combine left front/rear, split center) sound in a mpeg4 container. because that is what my ps3 will play back. i use ffmpeg's -cfq setting.
  # ffmpeg -i ${INFILE_THAT_FFMPEG_CAN_DECODE} -map 0:0 -map 0:1 -deinterlace -vcodec libx264 -vpre hq -crf 22 -threads 0 -level 41 -acodec libfaac -ac 6 -ab 256kb -r 24000/1001 ${INFILE_THAT_FFMPEG_CAN_DECODE%.*}.mp4 -map 0:1 -acodec libfaac -ab 256kb -newaudio
  The above gets generated with a lengthy python script that i'm till slowly working bugs out of.
  
  --
  All of the above was encrypted with a Quad ROT-13 method. Unauthorized decryption is in violation of the DMCA.
9. Re:any dvd professional by westlake · 2010-07-24 04:40 · Score: 1
  
  last I heard, there were rather high-profile examples of each indeed not having same.
  Of course there are.
  You owe MPEG LA nothing until you are distributing product on a commercial scale - and by commercial I mean the premium cable channel with a minimum of 100,000 paying subscribers. The broadcast station serving 500,000 households.
  H.264 royalties on sales of your 30 minute Star Trek fan-flick max out at 2 cents a disk or download. Wake them when you have a check for $20,000 to deliver.
10. Re:any dvd professional by isorox · 2010-07-24 04:58 · Score: 1
  
  And the problem is, where do you find raw, uncompressed video? About the only place you will find it is if you are transferring an analog source to a dedicated internal capture card. Virtually everything else uses some form of MPEG or H.264 compression.
  You don't. I work in the TV industry and don't get much access to uncompressed video, not from a camera anyway. In the SD world, the camera gets dropped down to a 270mbit stream (165mbit of video data), which uses YUV, compressing the chroma, and uses interlaced video, compressing the vertical resolution. We use anamorphic pictures too, so horizontal res is compressed. Even graphics tend to be a yuv422 stream. That's about the closest I get to uncompressed.
  In the HD world it's a similar issue, with 1080i at 1.5gbit (I've never seen 3gbit outside of IBC).
  While codecs exist for higher bitrates (2:1, 3:1 etc, upto about 80mbit), most of our SD work is 50mbt d10, 30mbit d10, and even dv25, giving a massive amount of compression before it even gets onto the editing system. HD tends to be 100mbit at most.
11. Re:any dvd professional by drinkypoo · 2010-07-24 04:59 · Score: 1
  
  H.264 royalties on sales of your 30 minute Star Trek fan-flick max out at 2 cents a disk or download.
  
  I will not knowingly support any scheme that penalizes my media's popularity, however trivial it might be.
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
12. Re:any dvd professional by isorox · 2010-07-24 05:06 · Score: 1
  
  270mbit stream (165mbit of video data)
  And I should add, that as it's interlaced, ffmpeg's x264 encode/decode unfortunately wins out against both vp8 and dirac at around 4mbit.
13. Re:any dvd professional by TJamieson · 2010-07-24 05:15 · Score: 1
  
  Nice script, but two things..
  First, ffmpeg's deinterlacer kinda sucks. Especially if you're working with NTSC broadcast (60000/1001fps) content, because really you want to be doing a pullup. Since in your example you're using 24000/1001, I guess it's progressive content. In that case, do you really need to deinterlace at all? If you do, you might be interested in the "top" parameter (see the manpage) for setting which field is first in interlaced content; usually it won't be necessary, but it's nice to have the ability. Just throw "-top -1" somewhere in there so it'll always autodetect, or if you want to get fancy, leverage ffprobe to tell you which field is first; I think you can do that with 'ffprobe -show_streams'.
  Second, I find a crf of 18 to 20 to be ideal for DVD content, particularly fast motion. Higher values tend to *just barely* starve the encoder of data during high/fast motion; it's more noticeable on a scaled-up display IMO.
  What are the opinions of other ffmpeg+x264 users out there?
  
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14. Re:any dvd professional by Anonymous Coward · 2010-07-24 05:25 · Score: 0
  
  So no WebM for you then. If you don't use a format that's widely supported today like Xvid & Mp3 in Avi or H.264 with AC3 or AAC audio in MKV or MP4 respectively that will severely penalize your media's popularity.
15. Re:any dvd professional by cynyr · 2010-07-24 11:42 · Score: 1
  
  Normally i'm doing dvd some progressive, some interlaced/telecine'ed content, some of it is interlaced, most isn't. I was under the impression that -deinterlace didn't do anything if the content wasn't interlaced. I'll look into the -top option. The full python code can be found at, http://github.com/cynyr/ps3enc It is a huge mess i know.
  
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16. Re:any dvd professional by TJamieson · 2010-07-24 12:48 · Score: 1
  
  Hey thanks for the link! A mess isn't a problem; hell, it's better than what I have -- nothing!
  I could be wrong about -deinterlace using cycles when it isn't necessary; I'm very much an amateur at this stuff still. For me, I've been using mencoder with -vf pullup,softskip for telecine'd content. It's slower, but the results (IMO) look better than ffmpeg, particularly for animation. For the mencoder tasks, I use a modified version of the script found at this blog: http://blog.dastrup.com/?p=34
  
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  For the last time, PIN Number and ATM Machine are redundancies!
17. Re:any dvd professional by PhillC · 2010-07-25 21:38 · Score: 1
  
  If you intend to edit the HD content, you might like it to be more than 100Mbps. For example, the default settings for ProRes HQ 50i content results in variable bitrate files up to 185Mbps and DNxHD 50i is 184Mbps. (60i content differs, with DNxHD at 220Mbps). AVC-Ultra (and AVC-Intra derivative) is up to 200Mbps.
  There are other sub-100Mbps options, such as XDCAM HD422 @ 50Mbps, but it really depends on your productions - high-end natural history and drama, then I'd want as much more than 100Mbps as my systems could handle. Factual, comedy and news/current affairs would most likely be fine at the lower bitrates. HD content is broadcast at atrociously low bitrates anyway. However, from an archival point of view, I'd like to see higher bitrates used.
  HDCamSR is only compressed at 440Mbps.
  
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18. Re:any dvd professional by isorox · 2010-07-26 05:34 · Score: 1
  
  If you intend to edit the HD content, you might like it to be more than 100Mbps.
  I might, however corporate strategy has settles on dvcpro-100 as the base codec. As it's news, a lot of the footage coming in has been squished through a satellite in any case, or at very best been shot on a 35 or 50mbit camera.
Code is specification. by Anonymous Coward · 2010-07-24 02:06 · Score: 0

You can't write a specification in a natural language like English. You can try, of course, and you can get pretty close, but there will always be ambiguities, and there were always be missing details.
The only way to fully specify software is to implement it. In doing so, you are specifying exact behavior not for other humans to interpret, but for a computer. A computer cannot handle ambiguities.
1. Re:Code is specification. by Anonymous Coward · 2010-07-24 02:36 · Score: 5, Informative
  
  One of the best ways I have seen to avoid that kind of ambiguities is in the PNG specification. (rfc2083)
  By not only explaining how something should be done but also expressing the reasoning to why this method has been chosen the person implementing the specification can follow the same reasoning and in the cases where the "how" not is specific enough the "why" will make it evident.
  One of the worst ways is probably rfc1034 with it's many "I think it should be done this way but I refuse to say if it is important or why I have chosen this method. Here is some pseudocode in a language that I just invented."
2. Re:Code is specification. by arekq · 2010-07-24 03:56 · Score: 1
  
  And then when the implementation has a bug, it never get fixed because, by definition, it is the specification, and alternate implementation have to introduce the same bug in their code.
3. Re:Code is specification. by willy_me · 2010-07-24 05:35 · Score: 2, Insightful
  
  By not only explaining how something should be done but also expressing the reasoning to why this method has been chosen
  Yes - a truly excellent thing to do. They should do the same thing with laws - define the law as they currently do but also provide a justification for the law. That way the law can be challenged in the future when the justification no longer holds. In addition, no one will ever misinterpret the meaning of a law and use it for purposes for which it was not designed.
  Now back to format specifications - code makes for a very poor specification. While code can implement a specification, it generally does so in an unorganized fashion. Specifications should be clear - having no ambiguities or vagueness. Code is not so clear. And as the parent mentioned, generally does not communicate reasoning to the reader.
  Mathematically based definitions are great - they are both clear and organized. Tools such as lex/flex/yacc/bison combine code with mathematical definitions to implement such specifications. The ideal format specification would include a mathematical definition along with reasoning explaining the design decisions.
4. Re:Code is specification. by sjames · 2010-07-24 07:54 · Score: 1
  
  Clearly written code with no 'clever' tricks can be part of a decent spec, but never all of it. Rationale matters as does an indication of possible future versions (is there a version field because we EXPECT to run against shortcomings or is it just future proofing).
  Even with code, ambiguity remains. If there are numerically tagged fields, MUST they be included in numerical order or did this code just happen to do that? When the code writes that struct onto the wire, is it big endian or little endian? In some cases, there is deliberately more than one way to do things within spec. In that case, example code will tell you ONE of them.
5. Re:Code is specification. by beelsebob · 2010-07-24 08:30 · Score: 1
  
  Not at all, mathematicians have figured out how to be precise many many many years ago. Admitedly dijkstra helped a lot, but mathematics has been able to produce exact specifications for much longer than programming has existed for.
6. Re:Code is specification. by Anonymous Coward · 2010-07-24 14:28 · Score: 0
  
  Yes - a truly excellent thing to do. They should do the same thing with laws - define the law as they currently do but also provide a justification for the law. That way the law can be challenged in the future when the justification no longer holds. In addition, no one will ever misinterpret the meaning of a law and use it for purposes for which it was not designed.
  
  It's a nice thought, but I can't see it actually working. The laws would have vague, weasel-word justifications like "We Believe That Children Should Not Be Harmed By Criminals". Anyone trying to repeal [whatever shitty, liberty-robbing law has to hide under such a syrupy guise] would look like they think harming children is the order of the day. Hell, look at the No Child Left Behind act - those opposed it are clearly in favour of leaving children behind!
  Though I do agree with justification for code, but only because coders generally don't have an agenda for choosing a particular methodology (and if they do, a plain-text justification could only ever expose the reason, rather than obfuscate it).
7. Re:Code is specification. by Hooya · 2010-07-24 14:44 · Score: 1
  
  is that a Pi in your face?
8. Re:Code is specification. by buchner.johannes · 2010-07-24 19:43 · Score: 1
  
  By not only explaining how something should be done but also expressing the reasoning to why this method has been chosen
  Yes - a truly excellent thing to do. They should do the same thing with laws - define the law as they currently do but also provide a justification for the law. That way the law can be challenged in the future when the justification no longer holds. In addition, no one will ever misinterpret the meaning of a law and use it for purposes for which it was not designed.
  That is what already happens in some European countries. It is part of being a judge to interpret laws while taking the intention of the lawmaker into account. Laws have accompaning documents that detail these (and you can tell from history/press from that time).
  
  Now back to format specifications - code makes for a very poor specification. While code can implement a specification, it generally does so in an unorganized fashion. Specifications should be clear - having no ambiguities or vagueness. Code is not so clear. And as the parent mentioned, generally does not communicate reasoning to the reader.
  Mathematically based definitions are great - they are both clear and organized. Tools such as lex/flex/yacc/bison combine code with mathematical definitions to implement such specifications. The ideal format specification would include a mathematical definition along with reasoning explaining the design decisions.
  In design theory there is the notion of explicit and implicit knowledge. Unless you are very reflective and a very experienced designer, you will not be able to make all your knowledge and your whole decision process explicit.
  There is also a theorem in logic preventing you from writing the perfect universally understood specification.
  
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Notice a pattern there? by /dev/trash · 2010-07-24 04:39 · Score: 0, Troll

You're a copyright infringer?
1. Re:Notice a pattern there? by imroy · 2010-07-24 04:54 · Score: 1
  
  Who said anything about copyright infringement? This is for personal use. There's no distribution to other parties involved.
2. Re:Notice a pattern there? by icebraining · 2010-07-24 05:01 · Score: 1
  
  What copyright? All the software he mentioned is OSS. H.264 is a format, it can't be copyrighted.
  Maybe you meant software patents? That depends on where he lives.
  
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3. Re:Notice a pattern there? by cynyr · 2010-07-24 11:51 · Score: 1
  
  seems like someone has a ps3. I'm doing the same thing to my dvd collection.
  
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4. Re:Notice a pattern there? by /dev/trash · 2010-07-24 13:24 · Score: 1
  
  The movies ya dolt.
5. Re:Notice a pattern there? by icebraining · 2010-07-25 01:49 · Score: 1
  
  Except he is encoding his own movies, since movies from P2P networks already come encoded (and nobody re-encodes, it would be stupid), and ripping his own DVDs/Blue-rays was considered fair use even if it breaks encryption, in the case RealNetworks v. DVD-CCA.
  
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Do any hardware players support matroska yet? by Joce640k · 2010-07-24 06:25 · Score: 1

Until I can play mkv files in a cheap DVD player then they're a non-starter for me. AVI might be rubbish but it works.
I also wanted to chop up a mkv file into pieces the other day and there doesn't seem to be an equivalent to VirtualDUB for this, I thought there would be something by now.
Is matroska gaining any support in the mainstream world or is it just another niche format like ogg?

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1. Re:Do any hardware players support matroska yet? by Anonymous Coward · 2010-07-24 07:33 · Score: 0
  
  Define cheap. If you want a MKV hardware player for around 100$ retail price that's perfectly doable. Google for WDTV and Xstreamer if you want a cheap hardware player that can decode just about anything. There are many other similar media players being made. Some of them have bit-torrent clients built in. Apart from that many companies (JVC, LG, Oppo, ...) produce Blu Ray players with built in MKV support and there are also TVs with USB ports that support it (Samsung IIRC, maybe others). I don't know about DVD players, but I haven't been looking.
  Then there is the fact that DivX choose the H.264/AAC/MKV combination as their new format about a year ago so support will only continue to spread. Most players support other codecs like AC3 audio as well so playing the typical 720p torrents is no problem. I recently read that Nokia's upcoming N8 phone will support those 720p MKVs out of the box.
  Basically if you want a good quality to filesize ratio, support for multible audio tracks, subtitles and chapters and that for resolutions up to 1080p with affordable hardware players the combination of H.264 video with AAC or AC3 audio and SRT or Vobsub subtitles in an MKV container has been the obvious choice for about two years.
  For the chopping part try Avidemux, but keep in mind that your source video will probably have huge keyframe intervals so you can't just cut on an arbitrary position without reencoding at least part of the video.
2. Re:Do any hardware players support matroska yet? by Joce640k · 2010-07-24 08:12 · Score: 1
  
  I guess these days I'm more interested in a USB connector than a plastic disc spinner.
  I'm not going to upgrade my TV to get mkv support, I'd be looking for a separate box. Is there a logo I should look for?
  
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3. Re:Do any hardware players support matroska yet? by Anonymous Coward · 2010-07-24 18:46 · Score: 0
  
  Apart from the DivX certified players there isn't really an encompassing logo. There are logos for H.264, MKV, AAC support etc. and you'll find about a dozen logos signifying all the capabilities on the manufacturers websites. I have a WDTV. It's very portable and plays everything, but it doesn't have a built in HD, Wifi or other extras like a bittorent client. If you need that (apart from the bt client) I know many people who are happy with a Xstreamer.
Xiph's support by ciaran_o_riordan · 2010-07-24 09:04 · Score: 1

Here's Xiph's support: http://www.xiph.org/press/2010/webm/ With Xiph's support, and now ffmpeg folk working on it, WebM's looking very good.

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Re: Perl spec by rduke15 · 2010-07-24 12:19 · Score: 1

A "bool" that can be TRUE, FALSE, "", "null", or "nan"
That's why I like Perl so much. Anything can be a Bool., and it's easy to understand: if it is "something" it is true; otherwise it is false (like 0, "0.0", "", undefined, or that NaN nonsense). It's the sort of thing that drives me crazy in places like PHP or Javascript, where you suddenly need "===" operators or crazy tests for something that should be completely obvious.
Of course, that makes offtopic, flamebait and whatnot all true.
If only that excuse worked. by /dev/trash · 2010-07-24 13:27 · Score: 1

Alas it does not.
Reasons for MKV by Anonymous Coward · 2010-07-24 14:46 · Score: 0

I use mkv, but only because it handles multiple streams very easily. If you just want 1 video + 1 audio stream, even avi can handle that. Add in 1 or more subtitles, some other audio streams, or chapters and mkv becomes a very handle container. mkvmerge GUI is dead simple for adding or removing streams.
If you have anything that requires mp4 or m4v, then nevermind.