On Sun, 15 Oct 2017 17:41:52 +0200, Nutchanon Wetchasit wrote: > > Hello, > > I ran into a problem on how alsa-utils's aplay command handles `-t` option > when I was trying to play a PCM WAVE file in loop, using following command: > > ( while true; do cat audio.wav; done ) | aplay -t raw -f S16_LE -r 44100 -c 2 > > An "audio.wav" can be any 44100 Hz 16-bit stereo PCM WAVE file, and `-t raw` > was specially specified to make aplay reject length information in the header. > However, once the command is run, first line of the output would read: > > Playing WAVE 'stdin' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo > > Which shows that aplay still read the input as WAVE format, despite the > `-t raw` option being explicitly specified. And you would notice that the audio > *does not loop*. Instead, it will play just once, followed by silence. > > However, if WAVE header was stripped out (or corrupted), aplay would now > treat the input as raw audio stream, and play a continuously repeated sound > as expected: > > ( while true; do dd if=audio.wav of=/dev/stdout ibs=44 skip=1; done ) | \ > aplay -t raw -f S16_LE -r 44100 -c 2 > > The first line of output would also show the stream as "raw data" too: > > Playing raw data 'stdin' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo > > This problem exists on the latest alsa-utils 1.1.4, as well as the older > 1.0.25 which came with my GNU/Linux distribution; though I'm not certain > whether this is also applicable to other file format (like Sun .AU) or not. > > Please investigate. > > Regards, > Nutchanon Wetchasit > > alsa-utils: 1.1.4 (source distribution) Try the git version of alsa-utils. This issue should have been already addressed along with the code refactoring. thanks, Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
