/* Audio Library for Teensy 3.X * Copyright (c) 2014, Paul Stoffregen, paul@pjrc.com * * Development of this audio library was funded by PJRC.COM, LLC by sales of * Teensy and Audio Adaptor boards. Please support PJRC's efforts to develop * open source software by purchasing Teensy or other PJRC products. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice, development funding notice, and this permission * notice shall be included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ #ifndef analyze_fft256_h_ #define analyze_fft256_h_ #include "AudioStream.h" #include "arm_math.h" // windows.c extern "C" { extern const int16_t AudioWindowHanning256[]; extern const int16_t AudioWindowBartlett256[]; extern const int16_t AudioWindowBlackman256[]; extern const int16_t AudioWindowFlattop256[]; extern const int16_t AudioWindowBlackmanHarris256[]; extern const int16_t AudioWindowNuttall256[]; extern const int16_t AudioWindowBlackmanNuttall256[]; extern const int16_t AudioWindowWelch256[]; extern const int16_t AudioWindowHamming256[]; extern const int16_t AudioWindowCosine256[]; extern const int16_t AudioWindowTukey256[]; } class AudioAnalyzeFFT256 : public AudioStream { public: AudioAnalyzeFFT256() : AudioStream(1, inputQueueArray), window(AudioWindowHanning256), prevblock(NULL), count(0), naverage(8), outputflag(false) { arm_cfft_radix4_init_q15(&fft_inst, 256, 0, 1); } bool available() { if (outputflag == true) { outputflag = false; return true; } return false; } float read(unsigned int binNumber) { if (binNumber > 127) return 0.0; return (float)(output[binNumber]) * (1.0 / 16384.0); } float read(unsigned int binFirst, unsigned int binLast) { if (binFirst > binLast) { unsigned int tmp = binLast; binLast = binFirst; binFirst = tmp; } if (binFirst > 127) return 0.0; if (binLast > 127) binLast = 127; uint32_t sum = 0; do { sum += output[binFirst++]; } while (binFirst < binLast); return (float)sum * (1.0 / 16384.0); } void averageTogether(uint8_t n) { if (n == 0) n = 1; naverage = n; } void windowFunction(const int16_t *w) { window = w; } virtual void update(void); uint16_t output[128] __attribute__ ((aligned (4))); private: const int16_t *window; audio_block_t *prevblock; int16_t buffer[512] __attribute__ ((aligned (4))); uint32_t sum[128]; uint8_t count; uint8_t naverage; bool outputflag; audio_block_t *inputQueueArray[1]; arm_cfft_radix4_instance_q15 fft_inst; }; #endif