I notice a AV desync after 5 minutes, it definitely happens when it reaches an advertisement that was cut out, or when I jump to a advertisement. :(
the only way I could "fix" it was to re-encode the edited recording with 'mencoder -ovc copy -oac copy -of mpeg -mpegopts format=pes2 -o new/001.vdr old/001.vdr'
I would see frames being skipped when it reaches where the cut took place...
I'm using vdr 1.6.0_p1
Theunis
On 23/07/2008, Martin Emrich emme@emmes-world.de wrote:
Hi!
Torgeir Veimo schrieb:
On 23 Jul 2008, at 23:06, Martin Emrich wrote:
(I wonder why there's no simple "TV simulator" that upmixes 50 fields/s to 50 frames/s just like a CRT TV?).
It's very hard to simulate this 'upmix'. A CRT TV actually moves the electron beam across the screen and the phosphor has some time it stays illuminated after being hit by the beam. This is very hard to simulate with a digital screen which is either on or off, or has some slowness by itself which is different from how a CRT screen works.
I did not mean to actually simulate the brightness decay in the phosphors, just the points in time where the fields are presented.
Let's assume we have two frames to be played back, which each consists of two fields: {1,2} and {3,4}.
I don't know if it actually works this way, but as far as I know, playing back interlaced content with 25 frames/s on a progressive display looks this way:
11111 33333 22222 ...1/25th sec. later: 44444 11111 33333 22222 44444
As field 3 is a 1/50th second "older" than field 4, there are jaggies in moving scenes.
What I am looking for would be this, with 50 frames/s:
11111 11111 33333 33333 ..... 1/50th s. 22222 1/50s 22222 44444 11111 11111 33333 33333 ..... 22222 22222 44444
So each field ist still being shown for a 1/25th of a second, but for the "right" 1/25th second. The output then no longer serves 25fps but 50fps to XVideo, DirectFB or whatever.
All of this of course makes only sense for PAL content when the TV can do 50Hz, not 60Hz.
The dscaler project has implemented some of the best deinterlacing algorithms and most of the tvtime algorithms are implemented (to my knowledge) with basis in dscaler source / ideas. See http:// dscaler.org/ . dscaler basically is a deinterlace and display program that takes input from bt8x8 based capture cards.
I assume these are the "tvtime" deinterlacers in the libxineoutput plugin. I played around with them, but none of them resultet in a picture as sharp and contrasty as without any deinterlacer. So I have to choose between sharpness and clean motions. And even during the EURO 2008, I chose the first.
Someone on that project had an idea to create a setup where the display hardware was synced to the input clock of the capture card, but I'm not sure if anything ever came out of that idea.
I also thought of that. One then would have to sync to the soundcard's buffer, too, and remove/duplicate samples as necessary, to keep the audio synchronized.
BTW: How does libxineoutput synchronize? I noticed a slight AV desync growing over ca. 5 minutes, the the audio jumps once and the desync jumps into the right position (Digital output to AV receiver).
Ciao
Martin
vdr mailing list vdr@linuxtv.org http://www.linuxtv.org/cgi-bin/mailman/listinfo/vdr