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Better Media Container Formats?
altaic asks: "Today I was looking for a container format to store my anime collection (multi-language audio and subs), and I discovered popular media containers actually suck. AVIs are a hacked mess and don't even support multiple audio tracks. OGMs are catching on, but they don't have an index, nor do they support variable framerates (the fps value is stored in the header). I found some info on the Matroska container, which looks really cool (it supports multiple subtitle streams, multiple audio streams, a slew of other nice features), as well as the very young MPCF (mplayer container format). I'd really like to hear about other people's experiences with newer, more useful media containers."
.WMV is a good format for video files. It's the native format for the most popular OS in the world, and some settop players can decode it in hardware.
Now, I understand the value in variable bit rates for efficency's sake. Unless I am wrong OGM supports supports VBR just fine. Now what would the use of variable frame rate be? Virtuall all video I can think of operates at a set frame rate for given display formats. (Mabye I'm just ignorant but hey, that seems useless)
I don't really mind double posts on
Multiple audio tracks AND multiple subtitle tracks can be muxed into AVI and play very well.
You'll need only these 2 tools to achieve this:
VobSub and MMSwitch
VobSub package contains the SubMux utility for muxing an AVI video, multiple audio tracks and subtitle files (in SRT, SUB, SSA and other formats) into AVI. MMSwitch will allow separate playback and easy selection of multiple audio tracks in any media player based upon DirectShow graphs, WMP for example.
In WMP, audio tracks and subtitle tracks can be then easily selected via context menu.
Well, if they are CDs you don't really care about, you can store them on a CD spindle. Otherwise, the old 5 1/4" floppy containers work fairly well.
You can also get some fairly nifty CD storage racks, like This one.
Oh, wait... You were talking about... Never mind.
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Please, just give me a file format that doesn't require me to do -aspect x:y whenever I launch mplayer... I'm trying to stick my dvd collection onto HDD (easier for moving between home and university) and it's driving me insane...
100 million downloads, support for multiple audio and video codecs, and best of all Windows Media is free software!!!
It was first raised in Feb2003 here.
The conversation died for a while, and then it was brought up again in March. (Although the conversation seemed to get bogged down on selecting a name for the format).
The format description is now included in the DOCS/tech directory of the mplayer tarball. Not sure whether any of it's actually implemented in the mplayer code.
Cool, but useless.
It may be that most media players can't deal with it, but the AVI format certainly supports multiple audio tracks, and it always has, as Google confirms. BTW, have you looked at MOV (QuickTime)? It's better than AVI, and it is better known than the other formats you list.
- It's well documented.
- Subtitles are easy with text atoms.
- It supports variable bit and frame rates.
- It can be hinted for rtsp streaming via the Open Source Darwin Streaming Server.
- They have an Index for fast seeking in large VBR files.
- They support as many audio and video tracks as you want.
Seriously - I don't know why more projects don't use it, it seems perfect to me...A lot of Animes are made with a philosophy of minimal cell count, so they will drop the frame rate at which the film is made in spots where they can get away with it. For stuff like this you could probably save a lot of space using variable frame rates.
Take a look at mpeg4. On my machine (OS-X) I use a program called OpenShiiva (http://openshiiva.sourceforge.net/) to dump DVD's. It uses mpeg4 for the container and Xvid or 3vix/AC3 for the audio-video stream. As far as changing frame-rates on the fly I don't know if that type of thing is in the spec or not. As far as subtitles and multiple audio streams I think it will work just fine. However I'm not an expert so feel free to correct me on this. Nice thing about mpeg4 is the mpeg standard. Hopefully you will be able to encode with either Xvid,Divx,3vix,Apple or M$ and playback on any mpeg4 complaint player. Once again your millage may vary, i've read in the 3vix forum that Xvid isn't quite mpeg4 complaint and I would imagine most of the other codecs have similar idiosyncrasies.
On the other hand there is Mov or Quicktime. This format is very mature and will play on most anything that Quicktime supports. It does allow for subtitles and multiple audio streams.
Although I think ogm is the container of choice for anime lovers....
Zorton
The quick-'n'-dirty answer is that, as long as you've got muxers and demuxers for the formats you're working with, converting from one container format to another is generally lossless, so you don't really need to worry about losing data to an obsolete format. In this layman's opinion (I'm not an A/V software programmer, but I play one on Slashdot), Matroska looks like a good choice here, since you can mux practically everything under the sun into a Matroska file. But be warned that practically-speaking not all of the existing Matroska filters recognize data like chapters; in contrast, formats like OGM may not support as much metadata, but the existing filters generally recognize all of it.
Couldn't the encoder just see the same frame repeated, and basically treat it as such? It'd make compression easy.
What about QuickTime? The format seems to be open, or at least known in various Free software libraries so that working with it is doable. You can use any number of codecs within a QT file, though.
And no, QT isn't one codec. There have been issues in the past about QT support on OSes like Linux- but that was because of a lack of support for the Sorensen codec that QT can use.
What are the limitations of QT? What does it do better or worse than AVI or the others? Myself, I've no clue, but would be intersted in finding out...
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They're practically the same thing in terms of container formats, and they're so extensible it isn't even funny.
Want multiple overlapping video tracks, various text tracks (perhaps one for each language, with the machine auto selecting, or asking the user if you want), SMIL support for web integration, sprite tracks, static picture tracks, built-in realtime effects, user interaction, chapter markers, searchable subtitles, etc?
It's all there, and *MUCH* more. most of people don't have a clue how absurdly versatile that format is, it's done everything you've asked for 'since the '90s.
"The worst tyrannies were the ones where a governance required its own logic on every embedded node." - Vernor Vinge
(Not a comprehensive list ;)
You CAN do 2 audio streams in AVI, just like you CAN do VBR MP3 in AVI, but it's not a good idea. By default, most media players will render both audio streams simulatenously, which is not what you want, unless the user has a filter like Morgan's Stream Switcher installed or uses an advanced player like BSPlayer or ZoomPlayer.
Using VBR MP3 in AVI requires the well-known "Nandub hack" now available in a few other programs as well. AVI is NOT designed to handle VBR audio formats, and it's time to let the format die.
If you mux subtitles into an AVI, I don't know that you can, for instance, move them into the area of the display below the video when running fullscreen if you have a widescreen movie.
MKV (Matroska) and Ogg (they don't officially recognize OGM) are good options because they support multiple audio streams easily and their filters are designed for it. VBR isn't a problem either... try seeking in a file using MKV or OGM and you can see that the audio and video stay right in synch from the moment you jump. With AVI, you're usually waiting until the next keyframe for them to get it in step. Furthermore, when you do mix multiple languages (audio or subtitle), you can encode a description with them, so you know which track is which language, a nice bonus. Lastly, both formats have less overhead than AVI, about 5-8 MB in 90 minutes or so, I forget the exact numbers, but that's more space you can use for your video if encoding yourself.
Don't forget they're all backwards compatible too... it's easy to pull the streams OUT of an MKV into their component parts and mux them back into AVI if you want (but you will take up more space, and I've never heard of AVI with 3+ audio streams).
"Recta non toleranda futuaris nisi irrisus ridebis"
I have many, many AVIs with multiple audio tracks. You just need to install the Morgan StreamSwitcher plugin. It's great for dvd rips with audiocommentary.
-Clio
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I don't know how good an ASF file is overall, but I know it supports multiple frame rates.
XML!
99% would be nice
... and we are already working on this, together with a very well respected company doing MPEG4 players. Dont expect it in the near future though, current decoder chips like the SIGMA EM 8550 are not powerful enough to decode MPEG4 video and Vorbis audio at the same time, and this is the most used profile in matroska files, followed by MPEG4 video and AAC audio ( together with SRT or SSA subs ) and RealVideo9 and Vorbis audio. Soon we will launch the latest features for matroska files, that will be the ability to store DVD subtitles ( vobsub's ) in MKV without the need to OCR them, and then MPEG2 video is the next on the list, so you can mix your SVCD video with Vorbis audio tracks :P ...
You are invited to visit us on irc.corecodec.com #matroska for more information
Christian
matroska project admin
http://www.matroska.org