[MPlayer-dev-eng] New inverse-telecine filter

[Billy Biggs]

Zoltan Hidvegi (mplayer at hzoli.2y.net):

> > > The bug is really in mplayer not supporting 411 TV capture (or
> > > 422, but NTSC is really just 411).
> > 
> >   Why do you say that NTSC is just 4:1:1 ?
> 
> NTSC have the same vertical chroma resolution as luma, but one quarter
> of the horizontal resolution, that's why I say that NTSC is 422, while
> YV12 is 420.

  You said NTSC is 4:1:1, why?  Studio NTSC is always stored and
transmitted as 4:2:2 (half the horizontal resolution for chroma, same
vertical resolution).  The only 4:1:1 storage and transmission format in
common use that I know of is DV.

> Much of the content on TV is originally progressive, broken up to
> interlaced fields, such as telecined movies or video from a 30fps
> progressive camera.

  I would say that most is true interlaced content, or at least more
than you imply (TLC, CNN, Comedy, any Sports broadcasts, ...).

> For such content the progressive content should be reconstructed, and
> normal progressive scaling should be used to get yv12.  But if you
> have hard interlaced content, you have to do interlaced scaling.  The
> TV card cannot figure this all out, the only right thing to do is to
> capture in 422 and do some de-interlacing before the yv12 conversion.

  If you are intending to convert to YV12 I would agree with you:
capture in 4:2:2 and do all processing before converting to any 4:2:0
format, and indicate in your output whether the YV12 frame is interlaced
or progressive (like the progressive_frame flag in MPEG2).  Similarly,
if you're just watching TV, keep it in 4:2:2 right to the display.
That's what I do in tvtime.

  But if youre capturing in YV12, then it's a bug in bttv if it does not
give interlaced chroma, there is no way around that.

  -Billy