I'm trying to write a program to display PCM data. I've been very frustrated trying to find a library with the right level of abstraction, but I've found the python wave library and have been using that. However, I'm not sure how to interpret the data.
The wave.getparams function returns (2 channels, 2 bytes, 44100 Hz, 96333 frames, No compression, No compression). This all seems cheery, but then I tried printing a single frame:'xc0xffxd0xff' which is 4 bytes. I suppose it's possible that a frame is 2 samples, but the ambiguities do not end there.
96333 frames * 2 samples/frame * (1/44.1k sec/sample) = 4.3688 seconds
However, iTunes reports the time as closer to 2 seconds and calculations based on file size and bitrate are in the ballpark of 2.7 seconds. What's going on here?
Additionally, how am I to know if the bytes are signed or unsigned?
Many thanks!
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