Re: Plextor PVR PX-M402U/PX-TV402U

Nathan Lutchansky <lutchann-v4l@xxxxxxxxxx> · Fri, 11 Mar 2005 10:43:40 -0500

On Fri, Mar 11, 2005 at 09:10:12AM -0600, James A. Pattie wrote:
> Roger Oberholtzer wrote:
> | It does look interesting. My only question is how one could stream data
> | to arbitrary files, knowing when a start scene is provided. Perhaps even
> | being able to request one. I would like to collect images to a number of
> | files (say, one file per hour) without a break in between the files. And
> | each file should be able to start playback at the start without the need
> | to look at the previous file. It would be nice if the v4l2 API addressed
> | this kind of thing so that drivers could supply this if the hardware
> | supports it.
> 
> I've downloaded the sdk but not yet looked at it, but if it works anything 
> like
> the ivtv project does, if your recording app only opens the /dev/video0 (or
> whatever device) once, then you could open and close your output files
> independantly to create seperate chunks.

It's not really interoperable with IVTV.  IVTV only supports read/write IO
(at least, the stable branch does) and the GO7007 driver only supports
mmap'd IO.  Also, the GO7007 delivers MPEG elementary streams only and has
no hardware audio encoding, so you have to mux the streams in software
yourself.

As far as breaking files up at a scene change, it should just be necessary 
to look for a frame with a GOP header and make that the first frame of the 
new file.  Nothing magic there.  I'll see if I can work something like 
that into the example app for the next release.  -Nathan