Re: [xine-devel] Disabling deinterlacing during still frames?

[R. B. <ro...@pa...>]

A hungover Michael Roitzsch reports:
 > To my current knowledge (<- I write this mostly because of the special brain 
 > state associated with the given date. ;) ), neither the demuxer nor the input 
 > plugin have the power to do so. 

Hmmm, maybe the input plugin can do it the same way that a
user-interface would do it by issuing some sort "get deinterlace state" command,
"turn deinterlace off" and then restore it when the still is left. Thoughts? 

 > Only the video decoder can do this detection 
 > and signal the output the interlaced state of the frame. Is there anything in 
 > those VCD stills a decoder could use to detect them safely?

The xine VCD plugin knows that it is inside a still frame from
navigation info (i.e. information in that first ISO-9660 track). It
has this before the still gets played.

Which reminds me of one other thing. I notice that if seeking
capability is reported off on entry to the still (i.e. early) then the
automatic MPEG detection won't register (I guess it needs seeking for
rewinding) and there's no demuxer available. If it is turned off after
the still frame is read, I don't see calls to query the new state. I'm
not sure this is causing a problem, but it is a little odd and bring
it up in case someone has any comments.

 > 
 > > I'm not sure I understand how this is done say for DVDs.
 > 
 > The MPEG2 stream has a progressive frame flag, which is hopefully set 
 > correctly by the DVD author. (Which is not always true, of course.)

I suppose that might be another way to do it. Somehow modify the block
before it is returned so it has the progressive flag to set off.