Ffmpeg

These are the steps to convert a set of frames (in the format frame_xxxxx.bmp) to a video.

Some options

• -f image2 : to start from a set of frames (not a video)
• -i input : the input value
• -r xx.xxxx : frames per second (that is, fps given by the camera when recording)
• -b xxxxk : specify the bitrate (higher = better quality, larger file size)
• -threads 0 : optimal thread usage
• -an : no audio
• -vcodec libx264 : uses the best and newest codec
• -vpre xxxx : codec quality (see here )
• output.ext : output is the name of the file, ext is the extension. Note that selecting mp4 or avi produces different files (is not just a name!)

Examples

• Low quality video, fast result:

ffmpeg -f image2 -r 12.0205 -i frame_%05d.bmp -vcodec libx264 -threads 0 -an -vpre fast video_fast.avi

• High quality (slow, high quality)::

ffmpeg -f image2 -r 12.0205 -i frame_%05d.bmp -vcodec libx264 -threads 0 -an -vpre hq -b 2000k video2000k.avi

• High quality, 2 pass (very slow, even higher quality):
  • note that there are actually two commands (hence the &&), the first generates the first pass to get the info necessary for the second pass. The command generates 4 files: video_2pass1.avi (the first pass, useless, can be deleted), video_2pass2.avi (the video itself, to keep) and 2 log files (delete them if you need to create another 2pass video)

ffmpeg -f image2 -r 12.0205 -i frame_%05d.bmp -an -vcodec libx264 -threads 0 -vpre fastfirstpass -b 2000k -pass 1 video_2pass1.avi &&
ffmpeg -f image2 -r 12.0205 -i frame_%05d.bmp -an -vcodec libx264 -threads 0 -vpre hq -b 2000k -pass 2 video_2pass2.avi

Useful links

• http://juliensimon.blogspot.com/2009/01/howto-ffmpeg-x264-presets.html
• http://rodrigopolo.com/ffmpeg/cheats.html

--Manubrambi 09:05, 10 October 2011 (UTC)