#include "loudness.hpp" #include "soundmanagerimp.hpp" namespace MWSound { void analyzeLoudness(const std::vector &data, int sampleRate, ChannelConfig chans, SampleType type, std::vector &out, float valuesPerSecond) { int samplesPerSegment = sampleRate / valuesPerSecond; int numSamples = bytesToFrames(data.size(), chans, type); int advance = framesToBytes(1, chans, type); out.reserve(numSamples/samplesPerSegment); int segment=0; int sample=0; while (segment < numSamples/samplesPerSegment) { float sum=0; int samplesAdded = 0; while (sample < numSamples && sample < (segment+1)*samplesPerSegment) { // get sample on a scale from -1 to 1 float value = 0; if (type == SampleType_UInt8) value = ((char)(data[sample*advance]^0x80))/128.f; else if (type == SampleType_Int16) { value = *reinterpret_cast(&data[sample*advance]); value /= float(std::numeric_limits().max()); } else if (type == SampleType_Float32) { value = *reinterpret_cast(&data[sample*advance]); value = std::max(-1.f, std::min(1.f, value)); // Float samples *should* be scaled to [-1,1] already. } sum += value*value; ++samplesAdded; ++sample; } float rms = 0; // root mean square if (samplesAdded > 0) rms = std::sqrt(sum / samplesAdded); out.push_back(rms); ++segment; } } }