Blurry DVD/Tv out playback

[mahen]

Hi everyone !

Here's an issue I experience under both Linux/proprietary nvida drivers and a PC laptop under windows (radeon), with VLC (and, actually, also xine, mplayer).

Actually, the picture is very blurry when playing a DVD (not a divx or any other file format), with the TV Out (PAL TV). I tried with many different DVDs in several formats, different screenmodes, etc., with de-interlacing enabled or disabled. I actually have the feeling several pictures are superimposed (?). As soon as something moves, it becomes very blurry.

I guess this has something to do with interlacing, frequencies etc... It happens under Windows, Linux, nvidia tv out, radeon tv out, vlc, mplayer, xine... (But not with a dedicated piece of software that doesn't use libdvdcss like WinDVD).

Does anyone have an idea by any chance ?
Thanks a lot for reading
cheers !

[DJ]

The issue appears to be FFmpeg (or libmpgv) and shouldn't have anything to do with libdvdcss. If the encryption is removed (for example) the problem is still there.

All digital video is follow audio for sync. If the audio card is not accepting control from the program or properly controlling the video there will be issues ranging from crashing to simple jitter. This is noticed most in scenes of high motion where lots of elements are changing or slow horizontal pans. In dedicated hardware the use of a single crystal and PLLs (Phase Locked Loop chips) help keep all the required frequencies stable and the TVs refresh rate is generally a multiple of the video's frame rate. In computers this in NOT true.

I agree mpeg 2 could (should) be improved in the light of other programs like WinDVD 7 in particular. But even WinDVD 7 can have problems if the hardware is not locking properly or there is frequency drift or the monitor refresh rate is not a multiple of the frame rate.

Depending on your equipment the Skip frames option in Preferences, Video may help. For older machines this should be on and for newer machines it should be off. The default is on and this effects MPEG only.

BTW DVDs are not interlaced. They have been through a 3:2 pull down process that makes them backward compatible to 4x3 TVs and can be considered progressive video because of this. If you feel that the majority of the DVDs you watch are interlaced either you have hardware problems or the DVDs your buying aren't a true 3:2 pull down. This is true for many Asian DVDs and most noticed in Anime series. It appears that even in 2007 the Telecine operators in various Asian countries still don't know how to set up their equipment.