Currently, when the audio capture device is opened, the kernel applies these settings 1. The DC mode enable setting is disabled 2. The bias voltage is enabled
Both are settings that allow the built in mic to get enabled properly. The rationale of applying these settings is that if Activities quit prematurely without properly closing the capture device,another Activity that uses this device, mustn't need to do anything special to get a default recording stream from the mic. The flip-side of applying these settings is that using an alsa interface, say such as pyalsaaudio to acquire a specified certain number of samples makes it impossible to get these samples at anything but the default settings. This is because when the specified call to get samples opens the capture device, the kernel overrides with the default settings (outlined in point 1 and 2 in the beginning of this email) My suggestion -- apply default settings only at close of capture device and not while opening it Given the current settings, I am out of ideas of how to write code that allows one to, at-will request for _a_ sample from the ADC at a specified set of capture settings and get it. Any suggestions ? -- Arjun Sarwal _______________________________________________ Devel mailing list [email protected] http://lists.laptop.org/listinfo/devel
