On Tuesday 23 July 2002 05:42, [EMAIL PROTECTED] wrote: > > The TV 'deinterlaces' the frame > > then (on a 'natural way' if you have 50/60Hz or electronic if you have a > > better 100/120Hz). > > The TV? You mean on a progressive scan TV, no? A regular TV will > just show the odd field then the even field as the video card has sent > it, just like it were broadcast, no? OK, forget that. What I wanted to say is that, when you have TV as your favourite output device, it's bad to deinterlace in software.
> > Therefore it's also very important to have the exact size on the VGA > > screen. > > You mean it's important that your framebuffer (to the TV) has the same > number of lines as your broadcast standard? Yes! > Right now, the only timings I have for NTSC at 640x480 have the image > overscanned vertically too much and the horizontal display is too > narrow, leaving a big black border on the right. Images look tall and > skinny. I also needed some time to find good settings. I don't know why this has to be so difficult. > > Also you have to make sure that you flip your frame buffer (which > > contains two fields) only when the output begins a new frame (the odd > > field). > > Right. MPlayer/directfb seem to be doing that correctly now. Seems > to work pretty well with the vsync patch in the DirectFB/patches > directory. That's interesting. I had much problems with mplayer/DirectFB. In DirectFB I measured the time between two vsync interrupts. I was 20ms and that is the time for one field. That means, when you sync against that you may have a chance of 50% to sync on correctly or not. > > If you have a progressive output all is very easy. The TV-out hardware of > > the G400 will do the job. > > I don't. I have a regular ol' television. Odd and even interlaced > fields. But you said above that the G400 does the right thing and > outputs the odd and even fields of the frames as the TV would like to > replicate the broadcast display, no? I mean the G400 will send your progressive frame as two fields to the TV. Because the two fields belongs to the same picture one can't see synchronisation problems so easily. Just be sure we talk about the same thing. Progressive frame means that the whole picture is taken at one moment. On a interlaced frame, there are two fields taken at different moments. > How important are > the maven patches? What sorts of things do they do? I noticed > quite a bit of maven stuff in one of them. What is this all about? > Does any of it matter if I don't have any application support using > it? i.e. does any of the maven patches alter the "general" or > "default" functionality of the framebuffer or does it just add > enhancements that applications can enable? The parameter patch was important to get a good picture. The picture was very dark and had less contrast with the original kernel. I don't know how it looks an a NTSC TV. Perhaps it's ok, then you don't need that patch. All matroxfb patches will go into the 2.5 kernel. The Resync patch adds an ioctl to restart the G400 TV-out sequencer. I use that to synchronize the G400 against the video stream. It works but could be improved. The patches for DirectFB are important to get the events handled for my application. I had problems to get all events into my application. > > Do you use matroxset to put the BES on your G400's TVout (2nd) head or > do you run it without the BES? I tried to get it to work without the > CRTC re-routing but could not get even a display on /dev/fb0. I don't use the BES, because gdk_directfb uses the primary layer only. Mixing the BES layer with the primary layer is something what seems to be impossible. At least I didn't found a way to do that. > Also, when you use fbset to report your framebuffer's timings, what > frequency does it report? Am I correct in assuming that for purposes > of doing TVout with the G400 framebuffer, the frequency is ignored and > is actually the frequency of your television? So all that matters is > adjusting the values to get a well centered, sized picture? This is still a miracle for me, but somehow the matrox engeneers got it to provide different timings for the TV output and the monitor output. When you look at the frequencies of the fbset output, you see the frequencies of the monitor output. The timing of the TV-out is fixed for the TV-standard. What is nice is that as soon as you switch on the TV-out, the vsync switches from monitor to TV-out, i.e. the sync signal is generated by TV-out. Perhaps this is a little bit off topic here. When you want to go deeper into detail feel free to contact me by private email. Mike -- Info: To unsubscribe send a mail to [EMAIL PROTECTED] with "unsubscribe directfb-dev" as subject.
