Widescreen v2, does it work now?

[Chris]

Dongle 0.0.11 is my second attempt at widescreen support. (Not having a widescreen TV myself makes the process slightly more tricky.) Please refer to the other poll post to see what should work and what shouldn't. So, is it better now?

[agebel]

Works fine now. Format switch seems to be a few seconds to early, but it's fine. What I think is a little disturbing is that the menus are displayed in 16:9 format too, that looks a little stretched.

Very good work!

Have you planned to implement radio-support in the near future?

[riban]

Yep! This is good. As previously mentioned, aspect ratio switching occurs about 6 second early (both 4:3 to 16:9 and 16:9 to 4:3) on Channel 4 (UK, QAM 64). Are there multiple signals available from the demux? Perhaps there is a standard length of time / number of frames that broadcasters send out the signal in advance. It would be great if this could be sorted. Coming in to the programme is OK but leaving for an ad break distorts the programme picture for 6 seconds.

When exiting from the options menu, the TV switches aspect ratio to 4:3 then back to 16:9 quickly. No great shakes but if it's obvious why, it would be nicer for it not to happen.

Walt

[Chris]

Ok, the 6 seconds too early thing is because that is how far ahead the demuxer is from the stuff being played with the video chips. (Should be a lot lot closer for live tv as I still havn't got prebuffering working!)

The demuxer detects the change in aspect ratio and sets the format for the TV. Then the data goes into the buffers waiting to be played. The solutions are not exactly pretty. First off we could have smaller buffers for recording playback. That would shorten the time but not get rid of it. Secondly, I could set some kind of timer to change the aspect later, but a) wouldn't know exactly when to set the timer for, would just have to guess, b) how to destroy/modify the timer if the user navigates around inbetween the timer being set and it acting. That's why I left it as it is for now..... I think it's something I could write better later, because later we might have timecode detection in the MPEG data, in which case setting the timer for the right time would be solved. Later I might have written a timer system for events... That would also be a fairly important pre-requisite to setting a timer!

As for exiting the options screen, the only thing I can do about that is to detect whether the widescreen format was changed or not, and if not, then not do the reinit of video. The problem here is that re-setting the aspect ratio requires closing the file descriptor to the video chip, which in turn causes the aspect ratio scart line to revert back to 4:3.

[Chris]

agebel:

Yes, radio support is soon. I am currently working on improving the GUI internals and then I think I will tackle radio support. The problem with radio is that the audio chip seems to eat all the data instead of allowing some buffering. Otherwise it would have been done by now, most of the code is there and waiting to go.

If anyone wants to have a look at the audio chip eating all the data instead of buffering, please do... I think it could be something to do with the sync ioctl which I don't really understand fully yet. Maybe a look into mvpmc to see how it does it might do the trick...

[davep]

Can I put in a request for an option similar to the previous behaviour?

My telly dates from 1988, a time before widescreen, Dolby Digital and DTV. Its SCART expects +12v on pin 8 to switch from broadcast to A/V and doesn't understand the +6v widescreen option. Hence when selecting a 'wide' program on VOMP the TV switches back to broadcast - very confusing since it appears that VOMP is not changing channels correctly!

How about a 'nailed-up' 4:3 option which always presents +12v? Or should I start saving for a new TV 

Dave

[Chris]

Haha, ok ... Maybe it's the case that if the TV is 4:3 the scart switching should not be done. I wondered about that while writing it, whether I should switch it anyway - as it turned out it was easier to leave it switching since I had no reason not to. Maybe I'll meter my real freeview box to see what it does...