- From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
- Date: Fri, 25 Feb 2011 13:06:31 +1100
- To: David Singer <singer@apple.com>
- Cc: Bob Lund <B.Lund@cablelabs.com>, "public-html@w3.org" <public-html@w3.org>
On Fri, Feb 25, 2011 at 12:36 PM, David Singer <singer@apple.com> wrote: > > On Feb 24, 2011, at 17:29 , Silvia Pfeiffer wrote: > >> >> >> When you talk about videos that are slide shows, are you actually >> talking about videos or about a sequence of images (photos) that are >> also sparse along the timeline, so not really "moving images"? If they >> are encoded as video, it would be impossible to distinguish the data >> as a sequence of photos. The other case - basically an "image track" >> is not something we've ever discussed before and is not something that >> all containers have formats for FAIK. > > I mean a video track where the frame rate is like 1 frame every 10 seconds. Many, or even most, containers can express this, I think. > >> As for chapter images - I am not sure how they are encoded in >> QuickTime/MPEG, so if you know, please share. I would have thought >> that a text track with image urls could be sufficient for this. > > > An obvious choice is as above, using an I-frame-only coding (e.g. JPEG). Interesting... not quite the most efficient way to encode, but it certainly works. In this case I would probably think that a chapter text track is sufficient and it can then load a frame from the "chapter video track" as the image. This can even be done using a Canvas. Cheers, Silvia.
Received on Friday, 25 February 2011 02:07:23 UTC