[mythtv] Interlaced vs. Progressive

[Isaac Richards]

On Thursday 02 March 2006 23:59, David Asher wrote:
> Ok, I pretty much got this to work...  Buuuutttt... (there's always a
> but, isn't there?)
>
> One broadcaster here in the Boston area (WGBH) broadcasts a show on 2-1
> (a SD subchannel, 2-2 is HD).  The shows I've recorded on 2-1 oscillate
> between interlaced and progressive according to ffmpeg -- not good.
> Creates stutters as my code tries to enable and disable interlacing (I'm
> using bob).  I've already put a small (2 frame) hysteresis in to handle
> DVD playback (the DVD I tested with often has 1 interlaced frame is a
> sea progressive frames when wandering through the menus at the beginning).
>
> Any clever ideas how to deal with this type of issue?  By using the
> interlaced_frame info from ffmpeg I made NVP a slave to its knowledge.
> One thing that MIGHT work is I'm currently allocating and freeing the
> deint filters each time the flag changes -- I could keep the
> deinterlacer structures around after disabling -- maybe that could
> reduce the hiccups to where they weren't noticeable.

Yeah, there shouldn't be any reason to reallocate things when it changes.

> Anybody know how ffmpeg figures out whether a frame is interlaced?

frame headers.

Isaac