[FFmpeg-user] Deinterlace and change framerate with -vcodec copy

[Andrew Berg]

On 2011.05.23 03:19 PM, Peter Bašista wrote:
> My primary objective is to avoid reencoding whenever possible. I will
> rather keep using the deinterlace filters during playback.
That's not a bad idea.
> Then let me correct myself: Deinterlace video filters:
> 1) require video decoding
> 2) can only be applied to uncompressed video fields / frames
>
> This means that unless you want the uncompressed video, you will have
> to encode it afterwards.
Yes.
> I'll keep that in mind. Would it be okay to say:
>
> Deinterlace video filters:
> 3) may introduce only a very minimal losses
> 4) but they are never lossless
Yes. I would recommend doing some lossless (or near-lossless - CRF 15 or
lower works well if write speed and/or disk space is an issue) encodes
with Yadif and comparing it to what you get from your media player's
deinterlacer.
> > In any case, be sure to change the frame rate to 24000/1001 fps instead
> > of 24fps.
>
> Can you explain why?
Because usually, film is that rate and not exactly 24fps (just like NTSC
is 30000/1001fps and not exactly 30fps). The reason for this is that
24000/1001fps is easier to telecine into the NTSC standard than 24fps.