FFmpeg - 60p to 30i

[bunklung]

I am trying to add interlacing. I know that sounds funny, but I'd like to retain the motions in my videos and retain the highest resolution while staying within 4.1 level of AVC.

I want to convert video from 1080/60p to 1080/30i with FFmpeg. I know some people refer to 30i as 60i and vice versa. They all mean the same thing digitally to me. I do not want 30p. I already figured that one out.

I did a good old Google search and came up with nothing. There are tons of deinterlacing result, but very little specific results that pertain to adding interlacing. There are a few results that allow the input file (which is already interlaced) to stay interlaced.

My videos are AVC high@L4.2 1080/60p (59.94) 24mbps. I want them to be AVC high@L4.1 1080/30i (29.97) 12mbps peak, 8mbps avg).

[poisondeathray]

Have you considered 720p60 as an alternative ? Progressive encoding is far more efficient, and the actual vertical resolution you get from watching 1080i60 is substantially reduced, especially when post processing is applied. There are also deinterlacing artifacts (aliasing, jaggies)


If you still want 1080i60, one method is to do the interlacing in avisynth; you can still use ffmpeg if you want with the avs script (or any encoder that accepts avs scripts)

#source filter using 1080p60 source
AssumeTFF().SeparateFields().SelectEvery(4, 0, 3).Weave()


I'm not sure how to convert it to interlaced with ffmpeg only

[bunklung]

Well my TV is interlaced already. It's an old CRT based HDTV. It displays 720/60p as 720/30i. And it displays 1080 interlaced anyway. So if I have to half my horizontal resolution it's better to have half of 1080 and not half of 720.

I have this faint suspicion that FFmpeg doesn't do interlacing.

My Popbox is limited to level 4.1 of AVC

But in the end, if I can't get 1080/30i, then 720/60p is my next move.

[poisondeathray]

You can still use ffmpeg , you just have to feed the .avs script into it as input. ffmpeg accepts avs scripts

[bunklung]

Thanks for the tip. I know it's a solution, but it's not the solution I'm looking for. Please don't take that the wrong way.

I was hoping for a few switches to throw at FFmpeg and call it a day. I don't want to invest an hour of my time to figure out how avs scripting works (at least yet...). I know absolutely nothing about it.

[poisondeathray]

no problem, well hopefully someone knows how to do it in ffmpeg and drops by. If you don't get an answer, you could ask in other forums (e.g. doom9, doom10) . I looked quickly at the ffmpeg documentation and couldn't find anything on converting to interlaced