Lower CPU and less audio issues with video transcoding

[alindl]

Hiya,

Just started using subsonic for video and my dual core server was struggling with x264, just about working but filling up the CPU which isnt ideal for me. Also, ffmpeg was having issues transcoding 48khz to 44.1khz, i think this is in the config because mp3 doesnt support 48khz.

I'm now using this transcode line:

ffmpeg -ss %o -i %s -async 1 -b %bk -s %wx%h -ac 2 -v 0 -f flv -vcodec flv -acodec libfaac -

Which changes the audio codec to aac which supports 48khz so i removed the forced 44.1khz option. It also changes the video codec to flv1 format which is h263 and lower quality but also lower cpu requirements for encoding. This has sorted my audio stuttering and reduced my cpu usage by more than half so i hope it can help others too.

Thanks
--
Alex

[omegatotal]

This did not work for me with the current build(05/27/2012-static) of ffmpeg on windows

ffmpeg just exits with "Unknown encoder 'libfaac'"

perhaps you could provide more information as to your current configuration as well as the specific version/build/compile options of your ffmpeg

[alindl]

Sorry didnt realise that aac wasnt enabled on a base install. This is my ffmpeg config:

ffmpeg version git-2012-05-09-f8b536a Copyright (c) 2000-2012 the FFmpeg developers
built on May 9 2012 10:09:05 with gcc 4.6.1
configuration: --enable-gpl --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-nonfree --enable-version3 --enable-x11grab
libavutil 51. 50.100 / 51. 50.100
libavcodec 54. 21.100 / 54. 21.100
libavformat 54. 4.100 / 54. 4.100
libavdevice 53. 4.100 / 53. 4.100
libavfilter 2. 72.105 / 2. 72.105
libswscale 2. 1.100 / 2. 1.100
libswresample 0. 11.100 / 0. 11.100
libpostproc 52. 0.100 / 52. 0.100