Take the 2-minute tour ×
Video Production Stack Exchange is a question and answer site for engineers, producers, editors, and enthusiasts spanning the fields of video, and media creation. It's 100% free, no registration required.

I want to make an interlaced video with 50fps into a 25fps progressive, in the process i'm also reducing the size of the frame. Currently i am using avconv and there are deinterlacing options, however, they are not documented. So what i am afraid of is that they will actually start bleeding information i am trying to drop into the frames that i am trying to keep.

The only tool that i have found, that does a documented drop of even/odd frames is a plugin for AVIDemux, which unfortunately does not export into Ogg or even encode into Theora. When i attempt to dump into Huff codec (to not introduce quality loss due to reencoding) it demands that i split files at 4 GiB. So i can only use it for small videos.

Is there another tool that can help me?

share|improve this question
    
You could always do the 4gigabyte split and then cut them back together after (assuming Huff codec supports append operations without re-encoding, I'm not familiar with that particular codec.) –  AJ Henderson Nov 4 '13 at 14:15
    
@AJHenderson It is a possibility, and i was already looking at that, but it's a hack. I think i would rather try to figure out the avlib's code and create a 'drop-deinterlacer', but i was hoping that something like that already exists. –  Volodya Nov 4 '13 at 14:22
    
yeah, makes sense. I unfortunately have near 0 experience with AVIDemux or avlib. I'm an Adobe/Windows guy, just a few little things when I was working on writing programs to work with video. –  AJ Henderson Nov 4 '13 at 14:25

2 Answers 2

up vote 1 down vote accepted
+50

ffmpeg -i input -vf field,scale=123:456 output will do the trick, where 123:456 is your x:y frame dimensions for the output. The field filter just chucks away the fields it doesn't use. Documention on the field filter here. Note that you'll need extra stuff in the command to get good results - e.g. you'll probably want to specify codec details and so on.

share|improve this answer
    
Will give you 50 rep for this when the system permits me to. –  Volodya Jan 20 at 6:40

You could use ffmpeg:

ffmpeg -i input -vf framestep=2 output

This will output every second frame.

share|improve this answer
    
That doesn't actually do what is expected with the progressive video. The result is still the same vertical resolution, so it doesn't drop unneeded lines. –  Volodya Nov 8 '13 at 15:51

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.