> It seems to me that it would be nice if the pvrusb2 device could > automatically detect the aspect ratio of the incoming signal (whether > broadcast, composite or s-video) and set the flag accordingly. At > present, I have to visually decide what the intended aspect ratio is and > manually set ctl_video_aspect, which is inconvenient.
It would certainly be nice :-) Unfortunately, AFAIK, this is not an easy problem :-( For broadcast, you would probably need VBI support (this is how ivtv does it IIRC). For composite/s-video, if the thing feeding you the signal is a decoder that is supposed to be talking to a TV and you have verified that it can set the aspect ratio on a TV properly, then my (uneducated) guess would be that it does that by sending VBI signals through the composite/s-video cable as well, so you stumble on the above problem. Otherwise, it is pretty much impossible (but then impossible is a pretty strong word in the open source world, impossible things happen every day here :-). If the problem is VBI: It is true that once more ivtv has done a very large and important part of the difficult work (we love you hans :-) and I would surely like to implement VBI here (since this is the only way for me to have greek teletext; not even windows can do that ;-), but I cannot (yet) find how the VBI signal is coming through USB. The problem is that VBI support in windows works only in USB 2.0 mode and I can 't get usbsnoop to work in this mode (it only logs the initial handshake, nothing more :-( > I am particularly > interested in having this functionality for composite and s-video. > (Analog TV broadcasts have stopped here). But, I have to admit that I > don't even know if composite or s-video contains information about > aspect ratio. Would someone care to comment? In any case, I can only assume that this driver is eventually going to have VBI support, but I wouldn 't hold my breath since this is nobody 's day job. My advice would be for you to get a DVB card (since analog broadcasts have stopped there). This will probably solve your problem since this way the aspect_ratio information will be right in the mpeg stream from the source (I think). That 's all I know. Hope this helps, -Pantelis _______________________________________________ pvrusb2 mailing list [email protected] http://www.isely.net/cgi-bin/mailman/listinfo/pvrusb2
