[FFmpeg-user] u8 sample format is incompatible with aac

Carl Eugen Hoyos cehoyos at ag.or.at
Tue Dec 20 11:11:37 CET 2011

Tarun singhal <tsinghal18 <at> gmail.com> writes:

> ffmpeg -i a.mp4 -samle_fmt u8 -vcodec libx264 -acodec aac -strict
> experimental b.mp4
> This command gives error that: u8 sample format is incompatible with aac.
> Assuming s16 by default.

This is not an error, but a warning to inform you that the sample format had to
be changed to to fit the encoder's needs.

All aac encoders in FFmpeg currently only accept s16 (and none of the external
libraries accept u8 afaict, some would accept s24, s32 and flt).
Any reason you want to use u8?

Carl Eugen

More information about the ffmpeg-user mailing list