Media Conversion
From Vague Hope Wiki
Contents
Audio
aac to wav
$ mplayer -ao pcm a.aac -ao pcm:file="a.wav"
wav to mp3, mono, 192
lame -h a.wav a.mp3 lame -h -m m a.wav a.mp3 lame -h -b 192 a.wav a.mp3
fixing and info
mpg123 --rate 44100 --stereo --resync a.mp3 vbrfix a.mp3 exiftool a.mp3
extract audio from video
ffmpeg -i inputfile.flv -acodec copy output.mp3
GUI tool: soundconverter
flac to mp3
ffmpeg -i input.flac -ab 196k -ac 2 -ar 48000 output.mp3
Video
Tools
General guide: http://ubuntuforums.org/showthread.php?t=786095
mplayer
Transcode for Transformer. Burns in ass subs.
- mplayer from source.
- x264 from source.
- neroAacEnc binary (see 4th source),
- Ubuntu repo MP4Box.
- Need to manually supply $FRAME_RATE.
mplayer -benchmark -ass \ -vo yuv4mpeg:file=>(x264 --demuxer y4m --crf 22 \ --preset slow --profile main --level 3.1 \ --vbv-bufsize 14000 --vbv-maxrate 14000 \ --threads 2 --output video.264 - 2>x264.log) \ -ao pcm:fast:file=>(neroAacEnc \ -ignorelength -lc -q 0.6 -if - -of audio.mp4 2>nero.log) \ source.mkv MP4Box -fps $FRAME_RATE -add video.264 -add audio.mp4 final.mp4
Possible FPS detection:
mkvinfo source.mkv | grep -A5 "Track type: video" | grep duration
ffmpeg
Down-scale mp4:
ffmpeg -i source.mp4 -vcodec libx264 -vprofile main -preset slow -b:v 400k -maxrate 400k -bufsize 800k -vf scale=852:480 -threads 0 -acodec libfaac -ab 128k output.mp4
Note: can do 'scale=-1:480' to calculate width.