I've been lurking around these forums for a while and they've been a great help to me in the past. However, I've been researching this problem for the past 2 days or so and can't seem to find a solution even though I feel it should be fairly simple. What I want to do is read in the audio stream, and essentially ignore every frequency except for a specific one (or range), the particular one isn't really important at the moment. Anyways, I want to be able to detect when this frequency reaches a certain magnitude (ie the pi recognizes the frequency is playing) and record the time its detected. About I'll I've been able to figure out so far is how to record a wav file from the terminal using the arecord command. I seem to understand that I need to perform an fft on that file and read the magnitude of the corresponding frequency range, but I've hit a brick wall in attempting this. Any help would be greatly appreciated.
EDIT Sorry, I am not allowed to comment until I have a minimum of 50 posts, and I've found that most forum type sites I use do not notify the others in the conversation of the change. As for the multiple accounts, one I created on stack exchange, and the next time I logged in I clicked the google log in and not the stack exchange one. I apologize for any inconvenience and appreciate you moving my mistaken answer box to the correct location. I'd appreciate it if you cold direct me in deleting one of the accounts, but more importantly how to get numeric level for a specific frequency(or range) for either a wav file or input stream in python haha :).