On Wed, Feb 25, 2004 at 04:59:28PM +0100, Ronald Bultje wrote: > Hi Richard, > > On Wed, 25 Feb 2004, Richard Ellis wrote: > > You are trying to recreate TiVo pause live TV functionality, > > right? If so, this isn't going to quite work like you want. > > Until lavrec closes out a segment and moves on to a new segment > > (and you will need to use the %d segment filename syntax) you > > will be unable to view that segment. In other words, > > lavplay/lav2yuv will refuse to read the beginning of a file that > > lavrec is still recording into because the .avi or .qt > > (quicktime) header has not yet been set up. Only once lavrec > > closes out that segment and starts a new segment does the file > > header get setup and then lavplay/lav2yuv see the file as a > > playable .avi or .qt file. > > Quicktime shouldn't have that issue, should it?
When I last used quicktime, it did, but that was about a year ago now and prior to the change over to the new quicktime libs in the tools. I just stuck with avi after that in part because I also find it preferable to have 10 1.7G files to shuffle about vs. one single 17G file. Unless the manner in which the new quicktime libs handle the files has changed, it will have the same problems. As best I could tell, lavrec (or more correctly the quicktime/avi support libs) output a skeleton block at the front of the file that will become the file header when the file is closed, but is not itself a proper header. Because it's not a proper header, attempting to read the file while it's still being recorded into by lavrec results in the other tools complaining that they can't read the file. It's easy to test, simply start up a recording, and while the recording is happening, try to run lav2yuv/lavplay/glav on the file. This is also the same reason why an aborted recording is unreadable, because when recording aborts, the file is not properly closed out (no header updates happen) and so initially the file is unreadable. With avi, I discovered that all I needed to do was copy the header from another valid avi over to the broken file, and it would magically become readable (not perfectly, lav2yuv churns burning CPU for a bit before it starts reading the file, but it eventually does work). With quicktime, I never found a way to recover from an aborted recording session leaving the file unreadable. So I stuck with many little files and avi for this reason as well. At least with many little files, if the last file can't be recovered, only a small portion of the recording unreadable, not the whole entire recording. And with avi, I've had success just copying another files header over to the broken one. ------------------------------------------------------- SF.Net is sponsored by: Speed Start Your Linux Apps Now. Build and deploy apps & Web services for Linux with a free DVD software kit from IBM. Click Now! http://ads.osdn.com/?ad_id=1356&alloc_id=3438&op=click _______________________________________________ Mjpeg-users mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/mjpeg-users
