Hi Rashed, On Mon, Jan 19, 2015 at 17:53:44 +0530, Rashed wrote: > C:\AudioTools\ALAC>ffmpeg -i pcmfile_48k_16bit_5.1.wav -acodec alac -ac 6 > out.m4a
What happens if you omit "-ac 6"? > Output #0, ipod, to 'out.m4a': > Metadata: > encoder : Lavf56.19.100 > Stream #0:0: Audio: alac (alac / 0x63616C61), 48000 Hz, 5.1, s16p, 128 > kb/s This looks correct. > Channel(s) : 2 channels This doesn't. First of all, please inspect the resulting file out.m4a with "ffprobe" or "ffmpeg -i". There may be a mismatch between the file header and the actual stream. (I recall this having happened with mono versus stereo MPEG audio.) Secondly, please try this. Mediainfo and ffprobe both properly report 6 channels in my resulting file: $ ffmpeg -f lavfi -i "aevalsrc=sin(440*2*PI*t):s=48000:c=5.1" -c:a alac -t 10 out.m4a (And please inspect the resulting file.) The only other difference I can see is that your input file is reported as "6" channels instead of "5.1", with the additional message: > Guessed Channel Layout for Input Stream #0.0 : 5.1 which I can't reproduce, but which seems correct for this purpose anyway. Moritz _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
