mirror of https://github.com/bsnes-emu/bsnes.git
73 lines
1.5 KiB
C++
Executable File
73 lines
1.5 KiB
C++
Executable File
#ifdef NALL_DSP_INTERNAL_HPP
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struct ResampleAverage : Resampler {
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inline void setFrequency();
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inline void clear();
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inline void sample();
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inline void sampleLinear();
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ResampleAverage(DSP &dsp) : Resampler(dsp) {}
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real fraction;
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real step;
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};
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void ResampleAverage::setFrequency() {
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fraction = 0.0;
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step = dsp.settings.frequency / frequency;
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}
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void ResampleAverage::clear() {
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fraction = 0.0;
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}
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void ResampleAverage::sample() {
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//can only average if input frequency >= output frequency
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if(step < 1.0) return sampleLinear();
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fraction += 1.0;
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real scalar = 1.0;
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if(fraction > step) scalar = 1.0 - (fraction - step);
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for(unsigned c = 0; c < dsp.settings.channels; c++) {
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dsp.output.write(c) += dsp.buffer.read(c) * scalar;
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}
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if(fraction >= step) {
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for(unsigned c = 0; c < dsp.settings.channels; c++) {
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dsp.output.write(c) /= step;
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}
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dsp.output.wroffset++;
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fraction -= step;
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for(unsigned c = 0; c < dsp.settings.channels; c++) {
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dsp.output.write(c) = dsp.buffer.read(c) * fraction;
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}
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}
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dsp.buffer.rdoffset++;
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}
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void ResampleAverage::sampleLinear() {
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while(fraction <= 1.0) {
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real channel[dsp.settings.channels];
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for(unsigned n = 0; n < dsp.settings.channels; n++) {
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real a = dsp.buffer.read(n, -1);
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real b = dsp.buffer.read(n, -0);
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real mu = fraction;
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channel[n] = a * (1.0 - mu) + b * mu;
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}
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dsp.write(channel);
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fraction += step;
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}
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dsp.buffer.rdoffset++;
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fraction -= 1.0;
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}
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#endif
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