diff --git a/AudioMixer4_F32.cpp b/AudioMixer4_F32.cpp new file mode 100644 index 0000000..40e9757 --- /dev/null +++ b/AudioMixer4_F32.cpp @@ -0,0 +1,30 @@ +#include "AudioMixer4_F32.h" + +void AudioMixer4_F32::update(void) { + audio_block_f32_t *in, *out=NULL; + + out = receiveWritable_f32(0); + if (!out) return; + + arm_scale_f32(out->data, multiplier[0], out->data, AUDIO_BLOCK_SAMPLES); + + for (int channel=1; channel < 4; channel++) { + in = receiveReadOnly_f32(channel); + if (!in) { + continue; + } + + audio_block_f32_t *tmp = allocate_f32(); + + arm_scale_f32(in->data, multiplier[channel], tmp->data, AUDIO_BLOCK_SAMPLES); + arm_add_f32(out->data, tmp->data, out->data, AUDIO_BLOCK_SAMPLES); + + release(tmp); + release(in); + } + + if (out) { + transmit(out); + release(out); + } +} diff --git a/AudioMixer4_F32.h b/AudioMixer4_F32.h new file mode 100644 index 0000000..0b7af83 --- /dev/null +++ b/AudioMixer4_F32.h @@ -0,0 +1,37 @@ +/* + * AudioMixer4 + * + * Created: Patrick Radius, December 2016 + * Purpose: Mix up to 4 audio channels with individual gain controls. + * Assumes floating-point data. + * + * This processes a single stream fo audio data (ie, it is mono) + * + * MIT License. use at your own risk. +*/ + +#ifndef AUDIOMIXER4F32_H +#define AUDIOMIXER4F32_H + +#include +#include + +class AudioMixer4_F32 : public AudioStream_F32 { +public: + AudioMixer4_F32() : AudioStream_F32(4, inputQueueArray) { + for (int i=0; i<4; i++) multiplier[i] = 1.0; + } + + virtual void update(void); + + void gain(unsigned int channel, float gain) { + if (channel >= 4 || channel < 0) return; + multiplier[channel] = gain; + } + + private: + audio_block_f32_t *inputQueueArray[4]; + float multiplier[4]; +}; + +#endif \ No newline at end of file