On Tue, 19 Feb 2002, Billy Biggs wrote: > Wan Tat Chee (tcwan@xxxxxxxxx): > > > I apologize if this is a newbie question, but on the issue of > > interlace noise, how can I reduce the effect when *viewing* TV source > > via fbtv or xawtv? I notice that it is especially pronounced when > > using full screen mode. I don't notice it when viewing in windowed > > mode. This makes it unacceptable as a replacement for an actual > > television. > > If you want it to look as good as a television (framerate wise), you > can try out my (unfinished) deinterlacer: > > http://www.dumbterm.net/graphics/tvtime/ > I tried it on my system (Celeron 466, RH 7.1, kernel 2.4.17-0.12custom, XFree 4.1), and it taxes the system pretty heavily. The frame rate is probably about 10 fps, though the picture quality is much better than fbtv at full screen (800x600 @ 75 Hz), which has a lot of interlace noise (mismatch between odd and even fields). [The same setup in Win98 + DirectX 8.0 using the supplied LifeView TV app doesn't have any interlace noise, but exhibits slight frame dropping (jerky motion), but much better than what is seen under Linux] I'm wondering if there's a simpler way to achieve the objective of deinterlacing? (I'm still rather new to TV signal decoding). 1. Should it be done in the v4l2 driver (saa7134 in this case) or in the application (fbtv, etc.)? 2. Seems like the problem is not so obvious with a small window, I'm wondering if it's an issue with AGP memory bandwidth. In that case should offscreen double buffering help to solve the interlace problem? (copy odd & even field to offscreen buffer1, zap buffer1 it to the screen, while buffer2 is being updated with the next odd&even fields...). 3. Otherwise, can a simple anti-aliasing algorithm work? Regards, T.C. ---- Wan Tat Chee (Lecturer) School of Computer Science, Univ. Science Malaysia, 11800 Minden, Penang, Malaysia. Ofc Ph: +604 657-7888 x 3617 Internet: tcwan@xxxxxxxxx Web: http://nrg.cs.usm.my/~tcwan GPG Key : http://nrg.cs.usm.my/~tcwan/tcw_gpg.asc F'print : 2DB6 E00A 9B98 BD36 AF0A 0FE8 69D2 20E5 573C DBA3
