[FFmpeg-user] (de)-interlacing question

[Toerless Eckert]

On Tue, Nov 22, 2016 at 07:30:48PM +0000, Andy Furniss wrote:
> Toerless Eckert wrote:
> 
> >Well, but what i am claiming is that they where interlacing
> >progressive HD to create interlaced SD.
> 
> Maybe, if the master is 720p50. I don't think they would interpolate
> from 720p25 to do that though.

Yepp. Checked a new recording, and the H264 HD TS from Astra is
720p50 with actual 50 frames, the mediaportal H264 mp4 file is
720p50 but actually 720p25 with duplicated frames, and the MPEG2 SD TS
from Astra is 720i50. 

So the good news is that all the SD bits are full origin bits, but
that still leaves me wondering how to best deal with deinterlacing.
The threads i can find comparing different deinterlacing options
are quite inconclusive to me.

*sigh*

> >I thought it might have gotten a lot easier through all the
> >experience collected with motion estimation. Aka: work in the DCT
> >domain, interpolate motion vectors and residual error - or something
> >like that.
> 
> AIUI encoders get it easy in comparison to interpolation. An encoder has
> the ground truth for reference, so even if it can't find good motion
> vectors it can correct the difference with the residual or intra code a
> block.

Use ground truth from 50p recordings to create 25p reference streams to train 
a neural network.

Nnedi already seems to use a neural network for deinterlacing. Would guess
it's using a similar approach.

Cheers
    Toerless