Hi, I have an embedded device running linux 3.10.16 with alsa-lib 1.0.24.1. Regarding the audio part, I have: - Mono audio input : single microphone - Mono audio output : single speaker - Audio codec mc13783 - I2S link between the audio codec and the CPU.
My system does not define any specific .asoundrc file, only the /etc/asound.state file is specific, this file adjust the mixer elements of the mc13783 audio codec. When I record the audio input using arecord -c 2 option, everything is fine. I get a file with the right and left channels and only the right channel contains data. Indeed it's a mono audio input and the audio codec only transfer audio data on the I2S right slot. When I record the audio input using arecord -c 1 option, the behavior is not the one I would like to have ;) I get a file with only one channel which is fine but the amplitude is divided by two. Using the -v option I could figure out that in the second case the following transformation happens: # Transformation table: # 0 <- 0*0.5 + 1*0.5 This explains why the amplitude is divided by two. Would you know a way to avoid this conversion? I would like to have no conversion so 0 <- 0. Best regards, Paixao Julien. ------------------------------------------------------------------------------ Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ Alsa-user mailing list Alsa-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/alsa-user
