Perfect deinterlacing with ffmpeg - bob doubler

[rgr]

I want to do lossless deinterlacing in ffmpeg (dv-> h264).

And I can't find information on how to convert a 720x576 50i to a 720x288 50p using the bob doubler filter known from VD.
Theoretically the yadif = 1 filter works similarly, but it turns 720x576 50i into 720x576 50p which makes the resulting video unnecessarily large.

And here is the question - how can two frames recorded together in 1 frame 720x576 be divided into 2 frames with the size of 720x288?

It's simple in VirtualDub, but how do you do it in ffmpeg?

[poisondeathray]

separatefields

https://ffmpeg.org/ffmpeg-filters.html#separatefields-1

[jagabo]

Yes, separatefields. But it won't look good and the picture will bounce up and down. To get the proper aspect ratio on playback you'll need to specify the SAR too.

And here is the question - how can two frames recorded together in 1 frame 720x576 be divided into 2 frames with the size of 720x288?

Half (every other scanline) of each frame is discarded. All the even scanlines of one field, all the odd scanlines of the other.

I want to do lossless deinterlacing in ffmpeg (dv-> h264).

That is impossible unless you use x264 in lossless mode (qp=0) which will give you much larger files than the DV source.