Here is a good site that offers a useful discussion of a number of xvid options for ffmpeg. I have been using 'libxvid' most of the time, and 'mpeg4' when I wanted to use b-frames - I haven't been able to get a good result with b-frames and libxvid, for whatever reason. I am also using ffmpeg a lot for encoding xvid (except when I have a 5.1 channel audio that I want to keep, in which case I have to use virtualdub). So - which options would you recommend to get a quality based but small sized VBR result for a mobile media player (like a cell phone) in addition to my first try?įfmpeg.exe -y -i %1 -vcodec libxvid -bf 1 -qscale 4 -s 320x240 -acodec libmp3lame -aq 2 -ar 22050 -ac 2 -f mp4 "%~n1.mp4"
The same applies to LAME as MP3 encoder - although I try to use parameters which should create a quality based VBR MP3 audio stream, I am not certain if the result is as desired until I demultiplex the result and check it (and may the reason just be that ffmpeg writes a constant bitrate into its console output). There are just too many options and provided by ffmpeg (with too briefly documented value ranges), I am losing track of which have any relation to Xvid at all, and which range of values is useful in case of Xvid as video encoder. And in case of a constant quantization possibly not at all. there is the command line option "-trellis #", and because Xvid supports trellis quantization, encoding to MPEG4-ASP using libxvid probably uses Trellis if I add this option - but which (integer) parameter for this option would make sense? In case of Xvid possibly 0 and 1 in case of x264 possibly 0, 1 and 2. It seems to me that ffmpeg does not support codec specific options (like "-xvidencopts" in mencoder) but offers a lot of generic options instead, which may be supported by a specific codec or not. Which command line options of ffmpeg can I use / should I use for rather optimal results? yet?) and the audio with a constant quality as offered by LAME's VBR mode. To get rather optimal results, I'd try to have the video encoded with fixed quantizer (because Xvid does not really support a good "constant quality" algorithm like x264's CRF.
Let's imagine I'd like to encode "anything" to MP4 with Xvid MPEG4-ASP video and LAME MP3 audio because that's quite the best size/quality ratio my mobile media player supports.
offers a quite versatile and current build unfortunately there are so many options that I am hardly able to filter which of them are relevant for Xvid encoding with ffmpeg at all.
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