iphone - iOS 5 - how to programatically normalize a PCM audio sample? -

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iphone - iOS 5 - how to programatically normalize a PCM audio sample? -

i recording 16bit linear pcm file using avaudiorecorder, saving caf file.

now want normalize sound recorded. cannot find library, either apple or 3rd party, lets me iphone!

peak normalization takes general form, you'll have few conversions, optimizations, , error checking add together 16 bit signal:

double* const buffer(...); const size_t length(...); double max(0); // find peak (size_t idx(0); idx < length; ++idx) max = std::max(max, buffer[idx]); // process double mul(1.0/max); (size_t idx(0); idx < length; ++idx) buffer[idx] *= mul;

iphone ios audio normalization

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