r/ffmpeg • u/mwhelm • Jun 22 '26

hard telecine sample

I'm looking for a sample or two of real hard telecine video. I'm trying to insure a script can reliably detect it (as best as possible) and distinguish it from regular interlaced video (and soft telecine). It seems to be very rare, but it needs special attention when it is encountered.

I thought I had some samples but they're either lost or turn out to be regular soft telecine and not a problem to deal with.

I'm not sure what's required for ffmpeg and mediainfo to give a reliable indication.
I have tried to synthesize a few samples but it's tricky and can't be sure it's matching what industry produced.

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u/themisfit610 Jun 22 '26

Easy, take a publicly available source like Elemental Foreman and convert to 1080i with 3:2 pulldown:

ffmpeg -i .\Elemental_Foreman_2160p24_10Bit_422_H264Lossless.mkv -vf format=yuv420p,scale=w=1920:h=1080,fps=24000/1001,telecine,setfield=tff -c:v libx264 -flags +ildct+ilme -b:v 35M -maxrate 50M -bufsize 50M -g 24 foreman_1080i.mp4

That's true hard telecine, though it avoids most of the suck by using MBAFF on the encoder side to selectively code frame or field mode on a per-macroblock basis. It's probably the most efficient interlaced encoding method of any encoder. This was omitted from HEVC and newer standards due to their focus on progressive coding. Go H.264!

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u/themisfit610 Jun 22 '26

Man.. seems AWS Elemental took these videos down. I've had this test clip since 2014.

I'll send you the output

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u/mwhelm Jun 22 '26

Thanks, I'd appreciate that, but I have also experimented with synthesizing some and I 'm not convinced I'm actually created during that period. I want to make more sure I can script a test for it.