What would the creation of a AVI or MPG with 2 audio tracks tell me that I don't know yet? I can just use normal ffmpeg for that - ffmpegx is just a GUI transcoding tool based on ffmpeg and the latest ffmpegx release is more than 2 years old. Anyway, I did look at the AVI spec after this email (http://msdn.microsoft.com/en-us/library/dd318183%28VS.85%29.aspx) and found that while each track has a type and a language, there is no track numbering and there are no track identifiers. But I have found a track priority, which allows ordering the tracks, though I didn't find a single AVI file with nonzero wPriority. Cheers, Silvia. On Thu, Feb 4, 2010 at 6:57 AM, Frank Barchard <fbarchard at google.com> wrote:> On Mac the ffmpegx tool supports 2 audio tracks. ?Maybe worth checking out? > http://www.ffmpegx.com/index.html > > Creates AVI or MPG files with two audio tracks. > Supports subtitles?in VobSub, SubRip, MicroDVD, SubViewer, Sami, VPlayer, > RT, SSA, AQTitle, JACOsub and MPsubt formats > > On Tue, Feb 2, 2010 at 5:40 PM, Silvia Pfeiffer <silvia at silvia-pfeiffer.de> > wrote: >> >> On Wed, Feb 3, 2010 at 11:21 AM, Chris Double <chris.double at double.co.nz> >> wrote: >> > Excerpts from Frank Barchard's message of Wed Feb 03 13:11:15 +1300 >> > 2010: >> >> >> >> Yes, and its good to learn from DVD's too. >> >> DVD is a subpart of MPEG: http://www.mpucoder.com/DVD/vobov.html, >> http://dvd.sourceforge.net/dvdinfo/dvdmpeg.html . >> Uses the same functionality for tracks, iiuc. >> >> > It might be useful to look at the Matroska container format too. It >> > handle's multiple tracks iirc. >> >> Matroska is interesting, see >> http://www.matroska.org/technical/specs/index.html#Track . >> >> It has a TrackNumber and a TrackUID (the latter probably maps well >> onto Ogg serialnumbers) and a Name (human-readable). >> >> Further for display order it has a TrackOverlay element, which >> specifies a track to be an overlay onto another one. >> >> Cheers, >> Silvia. >> _______________________________________________ >> ogg-dev mailing list >> ogg-dev at xiph.org >> http://lists.xiph.org/mailman/listinfo/ogg-dev > >
DVD has the UI and the low level meta information. The API you propose is the glue between the 2. It also has practical content. Could a DVD like UI be implemented on top of your API? It may need more exploration features? Could your API be used on DVD content asis? Do your APIs have 1:1 relationship with meta information in the files? multiple languages requires language codes match up. Your example shows exact matches, but there are multiple versions of each language. role/type is tricky. commentary tracks on a movie may be different speakers in the same language. Does your API match what the underlying file formats expose? As far as I know, basic transcodes to ogg and mp4, dont translate language codes, and dont maintain type and role meta information? On Wed, Feb 3, 2010 at 9:49 PM, Silvia Pfeiffer <silvia at silvia-pfeiffer.de>wrote:> What would the creation of a AVI or MPG with 2 audio tracks tell me > that I don't know yet? I can just use normal ffmpeg for that - ffmpegx > is just a GUI transcoding tool based on ffmpeg and the latest ffmpegx > release is more than 2 years old. > > Anyway, I did look at the AVI spec after this email > (http://msdn.microsoft.com/en-us/library/dd318183%28VS.85%29.aspx) and > found that while each track has a type and a language, there is no > track numbering and there are no track identifiers. > But I have found a track priority, which allows ordering the tracks, > though I didn't find a single AVI file with nonzero wPriority. > > Cheers, > Silvia. > > > > On Thu, Feb 4, 2010 at 6:57 AM, Frank Barchard <fbarchard at google.com> > wrote: > > On Mac the ffmpegx tool supports 2 audio tracks. Maybe worth checking > out? > > http://www.ffmpegx.com/index.html > > > > Creates AVI or MPG files with two audio tracks. > > Supports subtitles in VobSub, SubRip, MicroDVD, SubViewer, Sami, VPlayer, > > RT, SSA, AQTitle, JACOsub and MPsubt formats > > > > On Tue, Feb 2, 2010 at 5:40 PM, Silvia Pfeiffer < > silvia at silvia-pfeiffer.de> > > wrote: > >> > >> On Wed, Feb 3, 2010 at 11:21 AM, Chris Double < > chris.double at double.co.nz> > >> wrote: > >> > Excerpts from Frank Barchard's message of Wed Feb 03 13:11:15 +1300 > >> > 2010: > >> >> > >> >> Yes, and its good to learn from DVD's too. > >> > >> DVD is a subpart of MPEG: http://www.mpucoder.com/DVD/vobov.html, > >> http://dvd.sourceforge.net/dvdinfo/dvdmpeg.html . > >> Uses the same functionality for tracks, iiuc. > >> > >> > It might be useful to look at the Matroska container format too. It > >> > handle's multiple tracks iirc. > >> > >> Matroska is interesting, see > >> http://www.matroska.org/technical/specs/index.html#Track . > >> > >> It has a TrackNumber and a TrackUID (the latter probably maps well > >> onto Ogg serialnumbers) and a Name (human-readable). > >> > >> Further for display order it has a TrackOverlay element, which > >> specifies a track to be an overlay onto another one. > >> > >> Cheers, > >> Silvia. > >> _______________________________________________ > >> ogg-dev mailing list > >> ogg-dev at xiph.org > >> http://lists.xiph.org/mailman/listinfo/ogg-dev > > > > >-------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.xiph.org/pipermail/ogg-dev/attachments/20100204/19d373e8/attachment.htm
On Fri, Feb 5, 2010 at 12:12 AM, Frank Barchard <fbarchard at google.com> wrote:> DVD has the UI and the low level meta information. > The API you propose is the glue between the 2. > It also has practical content. > Could a DVD like UI be implemented on top of your API? > It may need more exploration features? > Could your API be used on DVD content asis? ?Do your APIs have 1:1 > relationship with meta information in the files? > multiple languages requires language codes match up. ?Your example shows > exact matches, but there are multiple versions of each language. > role/type is tricky. ?commentary tracks on a movie may be different speakers > in the same language. ?Does your API match what the underlying file formats > expose? > As far as I know, basic transcodes to ogg and mp4, dont translate language > codes, and dont maintain type and role meta information?Language codes do translate. Right now, for Ogg, only the Kate track has language codes, so no language codes on audio or video. Type is just a mime type, so will be different between different codecs and container formts anyway. Role is a new thing that doesn't really match with anything existing. I will have a look at the DVD extensions over MPEG, because they may keep something like a "role" attribute. I wasn't actually after feedback on the API - the API is being developed over in W3C and I just quoted the current state. But if you have feedback on the API, on things that are missing, go ahead! I'm more than happy to learn. Cheers, Silvia.