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) libasound: 1.1.4 (source distribution) System: Debian GNU/Linux 7.0 "Wheezy" i386 P.S. The "audio.wav" I used in my testing is a siren sound generated by Sox: sox -b 16 -c 2 -e signed-integer -r 44100 -n audio.wav \ synth 0.5 sine 800 gain -6 : synth 0.5 sine 600 gain -6 _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
