i use costum action in thunar to convert audio files to aac. the script is very simple
ffmpeg -i file -nostdin -f wav - | fdkaac -I -m 2 - -o output
i use a pipe with ffmpeg because it supports more input formats. i want to keep the number of channels of the input file, except its more then 6, when the output file should have 6 channels. i dont need 6.1 or 7.1 or such things. i cant find an option to limit the channels in ffmpeg or fdk aac. there is only the option to set the channels to n. For that i need to edit the script: read out the channels of the input file and keep it or set the output channels to 6 if its a input with 6+ channels. before i do this i want to ask if there are option in ffmpeg or fdk aac to do this.