It’s a simple one-liner.

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## by JamesIsIn

ffmpeg -i /path/to/film/1080p.[extension] -vf "tinterlace=5" /path/to/film/1080i.[extension] 

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I did it with an mkv file, but it should work with a variety of file types. It may be restricted to the h264, but may also work with h265. Let us know about your test results.