From 70b8ce6c4449f36a29d7390a0740735a5217e089 Mon Sep 17 00:00:00 2001 From: boblark Date: Mon, 21 Feb 2022 21:13:33 -0800 Subject: [PATCH] Initial add of analyze_fft4096_iqem_F32 --- OpenAudio_ArduinoLibrary.h | 1 + analyze_fft4096_iqem_F32.cpp | 429 +++++++++++++++++++ analyze_fft4096_iqem_F32.h | 348 +++++++++++++++ examples/TestFFT4096iqEM/TestFFT4096iqEM.ino | 94 ++++ keywords.txt | 1 + 5 files changed, 873 insertions(+) create mode 100644 analyze_fft4096_iqem_F32.cpp create mode 100644 analyze_fft4096_iqem_F32.h create mode 100644 examples/TestFFT4096iqEM/TestFFT4096iqEM.ino diff --git a/OpenAudio_ArduinoLibrary.h b/OpenAudio_ArduinoLibrary.h index 21dea21..f6a957d 100644 --- a/OpenAudio_ArduinoLibrary.h +++ b/OpenAudio_ArduinoLibrary.h @@ -35,6 +35,7 @@ #include "analyze_fft1024_iq_F32.h" #include "analyze_fft2048_iq_F32.h" #include "analyze_fft4096_iq_F32.h" +#include "analyze_fft4096_iqem_F32.h" #include "analyze_peak_f32.h" #include "analyze_rms_f32.h" #include "analyze_tonedetect_F32.h" diff --git a/analyze_fft4096_iqem_F32.cpp b/analyze_fft4096_iqem_F32.cpp new file mode 100644 index 0000000..9d600df --- /dev/null +++ b/analyze_fft4096_iqem_F32.cpp @@ -0,0 +1,429 @@ +/* + * analyze_fft4096_iq_F32.cpp Assembled by Bob Larkin 9 Mar 2021 + * + * External Memory **** BETA TEST VERSION - NOT FULLY TESTED **** <<<<<<<<<< + * + * This class is Teensy 4.x ONLY. + * F32 Bolocks are always 128 floats, and any data rate is OK. + * + * Converted to F32 floating point input and also extended + * for complex I and Q inputs + * * Adapted all I/O to be F32 floating point for OpenAudio_ArduinoLibrary + * * Future: Add outputs for I & Q FFT x2 for overlapped FFT + * * Windowing None, Hann, Kaiser and Blackman-Harris. + * + * Conversion Copyright (c) 2021 Bob Larkin + * Same MIT license as PJRC: + * + * 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. + */ + +// *************** TEENSY 4.X ONLY **************** +#if defined(__IMXRT1062__) + +#include +#include "analyze_fft4096_iqem_F32.h" + +// Note: Suppports block size of 128 only. Very "built in." + +// Move audio data from audio_block_f32_t to the interleaved FFT instance buffer. +static void copy_to_fft_buffer1(void *destination, const void *sourceI, const void *sourceQ) { + const float *srcI = (const float *)sourceI; + const float *srcQ = (const float *)sourceQ; + float *dst = (float *)destination; // part of fft_buffer array. 256 floats per call + for (int i=0; i < 128; i++) { + *dst++ = *srcI++; // real sample, interleave + *dst++ = *srcQ++; // imag + } + } + +void AudioAnalyzeFFT4096_IQEM_F32::update(void) { + audio_block_f32_t *block_i,*block_q; + int i, ii; + + block_i = receiveReadOnly_f32(0); + if (!block_i) return; + block_q = receiveReadOnly_f32(1); + if (!block_q) { + release(block_i); + return; + } + // Here with two new blocks of data. These are retained until the FFT + // but with new pointers, blocklist_i[] and blocklist_q[]. + switch (state) { + case 0: + blocklist_i[0] = block_i; blocklist_q[0] = block_q; // Copy 2 ptrs + state = 1; + break; + case 1: + blocklist_i[1] = block_i; blocklist_q[1] = block_q; + state = 2; + break; + case 2: + blocklist_i[2] = block_i; blocklist_q[2] = block_q; + state = 3; + break; + case 3: + blocklist_i[3] = block_i; blocklist_q[3] = block_q; + state = 4; + break; + case 4: + blocklist_i[4] = block_i; blocklist_q[4] = block_q; + state = 5; + break; + case 5: + blocklist_i[5] = block_i; blocklist_q[5] = block_q; + state = 6; + break; + case 6: + blocklist_i[6] = block_i; blocklist_q[6] = block_q; + state = 7; + break; + case 7: + blocklist_i[7] = block_i; blocklist_q[7] = block_q; + state = 8; + break; + case 8: + blocklist_i[8] = block_i; blocklist_q[8] = block_q; + state = 9; + break; + case 9: + blocklist_i[9] = block_i; blocklist_q[9] = block_q; + state = 10; + break; + case 10: + blocklist_i[10] = block_i; blocklist_q[10] = block_q; + state = 11; + break; + case 11: + blocklist_i[11] = block_i; blocklist_q[11] = block_q; + state = 12; + break; + case 12: + blocklist_i[12] = block_i; blocklist_q[12] = block_q; + state = 13; + break; + case 13: + blocklist_i[13] = block_i; blocklist_q[13] = block_q; + state = 14; + break; + case 14: + blocklist_i[14] = block_i; blocklist_q[14] = block_q; + state = 15; + break; + case 15: + blocklist_i[15] = block_i; blocklist_q[15] = block_q; + state = 16; + break; + // ******************************************************** + // Once things are running, the loop comes back to this point + case 16: + blocklist_i[16] = block_i; blocklist_q[16] = block_q; + + // Now work on the FFT output data. This was created in case 31. + // This next forming of the sumsq[] takes 48 uSec + count++; + for (int i = 0; i < 2048; i++) { + // Re-arranging the coefficients. These are bin powers (not Volts) + // See DD4WH SDR + float ss0 = *(pFFT_buffer + 2*i) * *(pFFT_buffer + 2*i) + + *(pFFT_buffer + 2*i+1) * *(pFFT_buffer + 2*i+1); + float ss1 = *(pFFT_buffer + 2*(i+2048)) * *(pFFT_buffer + 2*(i+2048)) + + *(pFFT_buffer + 2*(i+2048)+1) * *(pFFT_buffer + 2*(i+2048)+1); + + if(!(pSumsq==NULL)) { // We have memory to do averages + if(count==1) { // Starting new average + *(pSumsq+i+2048) = ss0; + *(pSumsq+i) = ss1; + } + else if (count <= nAverage) { // Adding on to average + *(pSumsq+i+2048) += ss0; + *(pSumsq+i) += ss1; + } + } + else // No averaging is used + { + // Parts of pFFT_buffer are becoming available for + // temporary storage, but not all: + *(pFFT_buffer+i) = ss0; + *(pFFT_buffer+4096+i) = ss1; + // Now in pFFT_buffer 0,2047 and 4096,6143 + } + } + + // sumsq[] is filled. Wait to state==17 to convert to dBFS, etc + state = 17; + break; + case 17: + blocklist_i[17] = block_i; blocklist_q[17] = block_q; + + // This state==17 block takes 710 uSec for DBFS, but + // only 65 for POWER. DB conversions do not need to be under + // this interrupt and POWER output should be used if time is short. + if (pSumsq==NULL || count>=nAverage) { // Average is not being done or is finished + outputflag = false; // Avoid starting read() during block 17 to 18 + float inAf = 1.0f/(float)nAverage; + for (ii=0; ii < 2048; ii++) { + // xAxis, bit 0 left/right; bit 1 low to high + if(xAxis & 0X02) + i = ii; + else + i = ii^2048; + + if(xAxis & 0X01) + i = (4095 - i); + + if(!(pSumsq==NULL)) { // We have memory to do averages + if(outputType==FFT_RMS) + *(pOutput+i) = sqrtf(inAf* *(pSumsq+ii)); + else if(outputType==FFT_POWER) + *(pOutput+i) = inAf* *(pSumsq+ii); + else if(outputType==FFT_DBFS) + *(pOutput+i) = 10.0f*log10f(inAf* *(pSumsq+ii))-66.23f; // Scaled to FS sine wave + else + *(pOutput+i) = 0.0f; + } + else { // No averaging + if(outputType==FFT_RMS) + *(pOutput+i) = sqrtf(*(pFFT_buffer+ii)); + else if(outputType==FFT_POWER) + *(pOutput+i) = *(pFFT_buffer+ii); + else if(outputType==FFT_DBFS) + *(pOutput+i) = 10.0f*log10f(*(pFFT_buffer+ii))-66.23f; + } // End, no averaging + } // End of "over all i" + } // end of Average is Finished + state = 18; + break; + case 18: + blocklist_i[18] = block_i; blocklist_q[18] = block_q; + + // Second half of post-FFT processing. dBFS (log10f) is the big user of time. + if (pSumsq==NULL || count>=nAverage) { // Average is finished + + Serial.println(count); + + count = 0; // CHECK WHERE IS count++ ??? <<<<<<<<<<<<<< + float inAf = 1.0f/(float)nAverage; + // ii is the index to data source, i is for data output + for (int ii=2048; ii < 4096; ii++) { + // xAxis, bit 0 left/right; bit 1 low to high + if(xAxis & 0X02) + i = ii; + else + i = ii^2048; + + if(xAxis & 0X01) + i = (4095 - i); + + if(!(pSumsq==NULL)) { // We have memory to do averages + if(outputType==FFT_RMS) + *(pOutput+i) = sqrtf(inAf* *(pSumsq+ii)); + else if(outputType==FFT_POWER) + *(pOutput+i) = inAf* *(pSumsq+ii); + else if(outputType==FFT_DBFS) + *(pOutput+i) = 10.0f*log10f(inAf* *(pSumsq+ii))-66.23f; // Scaled to FS sine wave + else + *(pOutput+i) = 0.0f; + } + else { // No averaging being done + if(outputType==FFT_RMS) + *(pOutput+i) = sqrtf(*(pFFT_buffer+ii+2048)); + else if(outputType==FFT_POWER) + *(pOutput+i) = *(pFFT_buffer+ii+2048); + else if(outputType==FFT_DBFS) + *(pOutput+i) = 10.0f*log10f(*(pFFT_buffer+ii+2048))-66.23f; + else + *(pOutput+i) = 0.0f; + } + } + outputflag = true; + } // end of Average is Finished + state = 19; + break; + case 19: + blocklist_i[19] = block_i; blocklist_q[19] = block_q; + state = 20; + break; + case 20: + blocklist_i[20] = block_i; blocklist_q[20] = block_q; + state = 21; + break; + case 21: + blocklist_i[21] = block_i; blocklist_q[21] = block_q; + state = 22; + break; + case 22: + blocklist_i[22] = block_i; blocklist_q[22] = block_q; + state = 23; + break; + case 23: + blocklist_i[23] = block_i; blocklist_q[23] = block_q; + state = 24; + break; + case 24: + blocklist_i[24] = block_i; blocklist_q[24] = block_q; + state = 25; + break; + case 25: + blocklist_i[25] = block_i; blocklist_q[25] = block_q; + state = 26; + break; + case 26: + blocklist_i[26] = block_i; blocklist_q[26] = block_q; + state = 27; + break; + case 27: + blocklist_i[27] = block_i; blocklist_q[27] = block_q; + state = 28; + break; + case 28: + blocklist_i[28] = block_i; blocklist_q[28] = block_q; + state = 29; + break; + case 29: + blocklist_i[29] = block_i; blocklist_q[29] = block_q; + state = 30; + break; + case 30: + blocklist_i[30] = block_i; blocklist_q[30] = block_q; + state = 31; + break; + case 31: + blocklist_i[31] = block_i; blocklist_q[31] = block_q; + + // Copy 8192 data to fft_buffer This state==31 takes about 500 uSec, including the FFT. + // i & q interleaved data. + copy_to_fft_buffer1(pFFT_buffer+0x000, blocklist_i[0]->data, blocklist_q[0]->data); + copy_to_fft_buffer1(pFFT_buffer+0x100, blocklist_i[1]->data, blocklist_q[1]->data); + copy_to_fft_buffer1(pFFT_buffer+0x200, blocklist_i[2]->data, blocklist_q[2]->data); + copy_to_fft_buffer1(pFFT_buffer+0x300, blocklist_i[3]->data, blocklist_q[3]->data); + copy_to_fft_buffer1(pFFT_buffer+0x400, blocklist_i[4]->data, blocklist_q[4]->data); + copy_to_fft_buffer1(pFFT_buffer+0x500, blocklist_i[5]->data, blocklist_q[5]->data); + copy_to_fft_buffer1(pFFT_buffer+0x600, blocklist_i[6]->data, blocklist_q[6]->data); + copy_to_fft_buffer1(pFFT_buffer+0x700, blocklist_i[7]->data, blocklist_q[7]->data); + copy_to_fft_buffer1(pFFT_buffer+0x800, blocklist_i[8]->data, blocklist_q[8]->data); + copy_to_fft_buffer1(pFFT_buffer+0x900, blocklist_i[9]->data, blocklist_q[9]->data); + copy_to_fft_buffer1(pFFT_buffer+0xA00, blocklist_i[10]->data, blocklist_q[10]->data); + copy_to_fft_buffer1(pFFT_buffer+0xB00, blocklist_i[11]->data, blocklist_q[11]->data); + copy_to_fft_buffer1(pFFT_buffer+0xC00, blocklist_i[12]->data, blocklist_q[12]->data); + copy_to_fft_buffer1(pFFT_buffer+0xD00, blocklist_i[13]->data, blocklist_q[13]->data); + copy_to_fft_buffer1(pFFT_buffer+0xE00, blocklist_i[14]->data, blocklist_q[14]->data); + copy_to_fft_buffer1(pFFT_buffer+0xF00, blocklist_i[15]->data, blocklist_q[15]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1000, blocklist_i[16]->data, blocklist_q[16]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1100, blocklist_i[17]->data, blocklist_q[17]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1200, blocklist_i[18]->data, blocklist_q[18]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1300, blocklist_i[19]->data, blocklist_q[19]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1400, blocklist_i[20]->data, blocklist_q[20]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1500, blocklist_i[21]->data, blocklist_q[21]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1600, blocklist_i[22]->data, blocklist_q[22]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1700, blocklist_i[23]->data, blocklist_q[23]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1800, blocklist_i[24]->data, blocklist_q[24]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1900, blocklist_i[25]->data, blocklist_q[25]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1A00, blocklist_i[26]->data, blocklist_q[26]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1B00, blocklist_i[27]->data, blocklist_q[27]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1C00, blocklist_i[28]->data, blocklist_q[28]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1D00, blocklist_i[29]->data, blocklist_q[29]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1E00, blocklist_i[30]->data, blocklist_q[30]->data); + copy_to_fft_buffer1(pFFT_buffer+0x1F00, blocklist_i[31]->data, blocklist_q[31]->data); + + + // Apply the window function, if any, to the time series. Half size window buffer. + if(wNum!=NULL && pWindow) + { + for (int i=0; i < 2048; i++) { + *(pFFT_buffer + 2*i) *= *(pWindow + i); // real + *(pFFT_buffer + 2*i+1) *= *(pWindow + i); // imag + } + for (int i=0; i < 2048; i++) { // Second half + *(pFFT_buffer + 8191 - 2*i) *= *(pWindow + i); + *(pFFT_buffer + 8190 - 2*i) *= *(pWindow + i); + } + } + + // Teensyduino core for T4.x supports arm_cfft_f32 + // arm_cfft_f32 (const arm_cfft_instance_f32 *S, float32_t *p1, + // uint8_t ifftFlag, uint8_t bitReverseFlag) + // I & O are real/imag interleaved in 8192-float point array p1. + arm_cfft_f32(&Sfft, pFFT_buffer, 0, 1); + + release(blocklist_i[0]); release(blocklist_q[0]); + release(blocklist_i[1]); release(blocklist_q[1]); + release(blocklist_i[2]); release(blocklist_q[2]); + release(blocklist_i[3]); release(blocklist_q[3]); + release(blocklist_i[4]); release(blocklist_q[4]); + release(blocklist_i[5]); release(blocklist_q[5]); + release(blocklist_i[6]); release(blocklist_q[6]); + release(blocklist_i[7]); release(blocklist_q[7]); + release(blocklist_i[8]); release(blocklist_q[8]); + release(blocklist_i[9]); release(blocklist_q[9]); + release(blocklist_i[10]); release(blocklist_q[10]); + release(blocklist_i[11]); release(blocklist_q[11]); + release(blocklist_i[12]); release(blocklist_q[12]); + release(blocklist_i[13]); release(blocklist_q[13]); + release(blocklist_i[14]); release(blocklist_q[14]); + release(blocklist_i[15]); release(blocklist_q[15]); + + blocklist_i[0] = blocklist_i[16]; + blocklist_i[1] = blocklist_i[17]; + blocklist_i[2] = blocklist_i[18]; + blocklist_i[3] = blocklist_i[19]; + blocklist_i[4] = blocklist_i[20]; + blocklist_i[5] = blocklist_i[21]; + blocklist_i[6] = blocklist_i[22]; + blocklist_i[7] = blocklist_i[23]; + blocklist_i[8] = blocklist_i[24]; + blocklist_i[9] = blocklist_i[25]; + blocklist_i[10] = blocklist_i[26]; + blocklist_i[11] = blocklist_i[27]; + blocklist_i[12] = blocklist_i[28]; + blocklist_i[13] = blocklist_i[29]; + blocklist_i[14] = blocklist_i[30]; + blocklist_i[15] = blocklist_i[31]; + + blocklist_q[0] = blocklist_q[16]; + blocklist_q[1] = blocklist_q[17]; + blocklist_q[2] = blocklist_q[18]; + blocklist_q[3] = blocklist_q[19]; + blocklist_q[4] = blocklist_q[20]; + blocklist_q[5] = blocklist_q[21]; + blocklist_q[6] = blocklist_q[22]; + blocklist_q[7] = blocklist_q[23]; + blocklist_q[8] = blocklist_q[24]; + blocklist_q[9] = blocklist_q[25]; + blocklist_q[10] = blocklist_q[26]; + blocklist_q[11] = blocklist_q[27]; + blocklist_q[12] = blocklist_q[28]; + blocklist_q[13] = blocklist_q[29]; + blocklist_q[14] = blocklist_q[30]; + blocklist_q[15] = blocklist_q[31]; + + state = 16; + break; // From case 31 + } // End of switch & case 31 + } // End update() + // End, if Teensy 4.x +#endif diff --git a/analyze_fft4096_iqem_F32.h b/analyze_fft4096_iqem_F32.h new file mode 100644 index 0000000..a51a4e1 --- /dev/null +++ b/analyze_fft4096_iqem_F32.h @@ -0,0 +1,348 @@ +/* + * analyze_fft4096_iqem_F32.h Assembled by Bob Larkin 9 Mar 2021 + * + * External Memory **** BETA TEST VERSION - NOT FULLY TESTED **** <<<<<<<<<< + * + * Note: Teensy 4.x Only, 3.x not supported + * + * Does Fast Fourier Transform of a 4096 point complex (I-Q) input. + * Output is one of three measures of the power in each of the 4096 + * output bins, Power, RMS level or dB relative to a full scale + * sine wave. Windowing of the input data is provided for to reduce + * spreading of the power in the output bins. All inputs are Teensy + * floating point extension (_F32) and all outputs are floating point. + * + * Features include: + * * I and Q inputs are OpenAudio_Arduino Library F32 compatible. + * * FFT output for every 2048 inputs to overlapped FFTs to + * compensate for windowing. + * * Windowing None, Hann, Kaiser and Blackman-Harris. + * * Multiple bin-sum output to simulate wider bins. + * * Power averaging of multiple FFT + * + * Conversion Copyright (c) 2021 Bob Larkin + * Same MIT license as PJRC: + * + * From original real FFT: + * 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. + */ + +/* Does complex input FFT of 4096 points. Multiple non-audio (via functions) + * output formats of RMS (same as I16 version, and default), + * Power or dBFS (full scale). Output can be bin by bin or a pointer to + * the output array is available. Several window functions are provided by + * in-class design, or a custom window can be provided from the INO. + * + * Memory for IQem FFT. The large blocks of memory must be declared in the INO. + * This typically looks like: + * float32_t fftOutput[4096]; // Array used for FFT Output to the INO program + * float32_t window[2048]; // Windows reduce sidelobes with FFT's *Half Size* + * float32_t fftBuffer[8192]; // Used by FFT, 4096 real, 4096 imag, interleaved + * float32_t sumsq[4096]; // Required ONLY if power averaging is being done + * + * These blocks of memory are communicated to the FFT in the object creation, that + * might look like: + * AudioAnalyzeFFT4096_IQEM_F32 myFFT(fftOutput, window, fftBuffer); + * or, if power averaging is used, the extra parameter is needed as: + * AudioAnalyzeFFT4096_IQEM_F32 myFFT(fftOutput, window, fftBuffer, sumsq); + * + * The memory arrays must be declared before the FFT object. About 74 kBytes are + * required if power averaging is used and about 58 kBytes without power averaging. + * + * In addition, this requires 64 AudioMemory_F32 which work out to about an + * additional 33 kBytesof memory. + * + * If several FFT sizes are used, one at a time, the memory can be shared. Probably + * the simplest way to do this with a Teensy is to set up C-language unions. + * + * Functions (See comments below and #defines above: + * bool available() + * float read(unsigned int binNumber) + * float read(unsigned int binFirst, unsigned int binLast) + * int windowFunction(int wNum) + * int windowFunction(int wNum, float _kdb) // Kaiser only + * void setNAverage(int NAve) // >=1 + * void setOutputType(int _type) + * void setXAxis(uint8_t _xAxis) // 0, 1, 2, 3 + * + * x-Axis direction and offset per setXAxis(xAxis) for sine to I + * and cosine to Q: + * If xAxis=0 f=0 in middle, f=fs/2 on left edge + * If xAxis=1 f=0 in middle, f=fs/2 on right edge + * If xAxis=2 f=0 on right edge, f=fs/2 in middle + * If xAxis=3 f=0 on left edge, f=fs/2 in middle + * If there is 180 degree phase shift to I or Q these all get reversed. + * xAxis=1 is a mathemetically consistent method. It has positive frequencies + * on the right and negative ones on the left. The center is half the sample + * rate, both + and -. Uniormly sampled data lives in this circular world.rate. + * + * Timing, max is longest update() time: + * T4.0 Windowed, dBFS Out, 987 uSec <<<<<4095 || binNumber<0) return 0.0; + return *(pOutput + binNumber); + } + + // Return sum of several bins. Normally use with power output. + // This produces the equivalent of bigger bins. + float read(unsigned int binFirst, unsigned int binLast) { + if (binFirst > binLast) { + unsigned int tmp = binLast; + binLast = binFirst; + binFirst = tmp; + } + if (binFirst > 4095) return 0.0; + if (binLast > 4095) binLast = 4095; + float sum = 0; + do { + sum += *(pOutput + binFirst++); + } while (binFirst <= binLast); + return sum; + } + + // Sets None, Hann, or Blackman-Harris window with no parameter + int windowFunction(int _wNum) { + wNum = _wNum; + if(wNum == AudioWindowKaiser4096) + return -1; // Kaiser needs the kdb + windowFunction(wNum, 0.0f); + return 0; + } + + int windowFunction(int _wNum, float _kdb) { // Kaiser case + float kd; + wNum = _wNum; + if (wNum == AudioWindowKaiser4096) { + if(_kdb<20.0f) + kd = 20.0f; + else + kd = _kdb; + useKaiserWindow(kd); + } + else if (wNum == AudioWindowBlackmanHarris4096) + useBHWindow(); + else + useHanningWindow(); // Default + return 0; + } + + // Number of FFT averaged in the output + void setNAverage(int _nAverage) { + if(!(pSumsq==NULL)) // We can average because we have memory. + nAverage = _nAverage; + } + + // Output RMS (default), power or dBFS (FFT_RMS, FFT_POWER, FFT_DBFS) + void setOutputType(int _type) { + outputType = _type; + } + + // xAxis, bit 0 left/right; bit 1 low to high; default 0X03 + void setXAxis(uint8_t _xAxis) { + xAxis = _xAxis; + } + + virtual void update(void); + +private: + float32_t *pOutput, *pWindow, *pFFT_buffer; + float32_t *pSumsq; + int wNum = AudioWindowHanning4096; + uint8_t state = 0; + bool outputflag = false; + audio_block_f32_t *inputQueueArray[2]; + audio_block_f32_t *blocklist_i[32]; + audio_block_f32_t *blocklist_q[32]; + // For T4.x + // const static arm_cfft_instance_f32 arm_cfft_sR_f32_len1024; + arm_cfft_instance_f32 Sfft; + int outputType = FFT_RMS; //Same type as I16 version init + int count = 0; + int nAverage = 1; + uint8_t xAxis = 0x03; + + // The Hann window is a good all-around window + // This can be used with zero-bias frequency interpolation. + // pWidow points to INO supplied buffer. 4096 for now. MAKE 2048 <<<<<<<<<<<<<<<< + void useHanningWindow(void) { + if(!pWindow) return; // No placefor a window + for (int i=0; i < 2048; i++) { + // 2*PI/4095 = 0.00153435538 + *(pWindow + i) = 0.5*(1.0 - cosf(0.00153435538f*(float)i)); + } + } + + // Blackman-Harris produces a first sidelobe more than 90 dB down. + // The price is a bandwidth of about 2 bins. Very useful at times. + void useBHWindow(void) { + if(!pWindow) return; + for (int i=0; i < 2048; i++) { + float kx = 0.00153435538f; // 2*PI/4095 + int ix = (float) i; + *(pWindow + i) = 0.35875 - + 0.48829*cosf( kx*ix) + + 0.14128*cosf(2.0f*kx*ix) - + 0.01168*cosf(3.0f*kx*ix); + } + } + + /* The windowing function here is that of James Kaiser. This has a number + * of desirable features. The sidelobes drop off as the frequency away from a transition. + * Also, the tradeoff of sidelobe level versus cutoff rate is variable. + * Here we specify it in terms of kdb, the highest sidelobe, in dB, next to a sharp cutoff. For + * calculating the windowing vector, we need a parameter beta, found as follows: + */ + void useKaiserWindow(float kdb) { + float32_t beta, kbes, xn2; + mathDSP_F32 mathEqualizer; // For Bessel function + + if(!pWindow) return; + + if (kdb < 20.0f) + beta = 0.0; + else + beta = -2.17+0.17153*kdb-0.0002841*kdb*kdb; // Within a dB or so + + // Note: i0f is the fp zero'th order modified Bessel function (see mathDSP_F32.h) + kbes = 1.0f / mathEqualizer.i0f(beta); // An additional derived parameter used in loop + for (int n=0; n<2048; n++) { + xn2 = 0.5f+(float32_t)n; + // 4/(4095^2) = 2.3853504E-7 + xn2 = 2.3853504E-7*xn2*xn2; + *(pWindow + 2047 - n) = kbes*(mathEqualizer.i0f(beta*sqrtf(1.0-xn2))); + } + } + }; +#endif +#endif diff --git a/examples/TestFFT4096iqEM/TestFFT4096iqEM.ino b/examples/TestFFT4096iqEM/TestFFT4096iqEM.ino new file mode 100644 index 0000000..aafff49 --- /dev/null +++ b/examples/TestFFT4096iqEM/TestFFT4096iqEM.ino @@ -0,0 +1,94 @@ +// TestFFT2048iqEM.ino for Teensy 4.x +// Bob Larkin 9 March 2021 + +// Generate Sin and Cosine pair and input to IQ FFT. +// Serial Print out powers of all 4096 bins in +// dB relative to Sine Wave Full Scale +// EXTERNAL MEMORY FFT +// Public Domain + +#include "OpenAudio_ArduinoLibrary.h" +#include "AudioStream_F32.h" + +// Memory for IQ FFT +float32_t fftOutput[4096]; // Array to allow fftBuffer[] to be available for new in data +float32_t window[2048]; // Half size window storage +float32_t fftBuffer[8192]; // Used for FFT, 4096 real, 4096 imag, interleaved +float32_t sumsq[4096]; // Required if power averaging is being done + +int jj; + +// GUItool: begin automatically generated code +AudioSynthSineCosine_F32 sine_cos1; //xy=76,532 +// Optional +// (float32_t* _pOutput, float32_t* _pWindow, float32_t* _pFFT_buffer, float32_t* _pSumsq) +//AudioAnalyzeFFT4096_IQEM_F32 FFT4096iqEM1(fftOutput, window, fftBuffer); //xy=243,532 +AudioAnalyzeFFT4096_IQEM_F32 FFT4096iqEM1(fftOutput, window, fftBuffer, sumsq); // w/ power ave +AudioOutputI2S_F32 audioOutI2S1; //xy=246,591 +AudioConnection_F32 patchCord1(sine_cos1, 0, FFT4096iqEM1, 0); +AudioConnection_F32 patchCord2(sine_cos1, 1, FFT4096iqEM1, 1); +// GUItool: end automatically generated code + +void setup(void) { + + Serial.begin(9600); + delay(1000); + + // The 4096 complex FFT needs 32 F32 memory for real and 32 for imag. + // Set memory to more than 64, depending on other useage. + AudioMemory_F32(100); + Serial.println("FFT4096IQem Test"); + + sine_cos1.amplitude(1.0f); // Initialize Waveform Generator + + // Pick T4.x bin center + //sine_cos1.frequency(689.0625f); + + // or pick any old frequency + sine_cos1.frequency(1000.0f); + + // elect the output format, FFT_RMS, FFT_POWER, or FFT_DBFS + FFT4096iqEM1.setOutputType(FFT_DBFS); + + // Select the wndow function, designed by FFT object + //FFT4096iqEM1.windowFunction(AudioWindowNone); + //FFT4096iqEM1.windowFunction(AudioWindowHanning4096); + //FFT4096iqEM1.windowFunction(AudioWindowKaiser4096, 55.0f); + FFT4096iqEM1.windowFunction(AudioWindowBlackmanHarris4096); + + // Uncomment to Serial print window function + // for (int i=0; i<2048; i++) Serial.println(*(window+i), 7); + + // xAxis, bit 0 left/right; bit 1 low to high; default 0X03 + FFT4096iqEM1.setXAxis(0X01); + + // In order to average powers, a buffer for sumsq[4096] must be + // globally declared and that pointer, sumsq, set as the last + // parameter in the object creation. Then the following will + // cause averaging of 4 powers: + FFT4096iqEM1.setNAverage(20); + + jj = 0; // This is todelay data gathering to get steady state + } + +void loop(void) { + static bool doPrint=true; + float *pPwr; + + delay(10); + + // Print output, once + if( FFT4096iqEM1.available() && doPrint ) { + if(jj++ < 3)return; + for(int i=0; i<4096; i++) + { + Serial.print((int)((float32_t)i * 44100.0/4096.0)); + Serial.print(" "); + Serial.println(*(fftOutput + i), 8 ); + } + doPrint = false; + } + Serial.print(" Audio MEM Float32 Peak: "); + Serial.println(AudioMemoryUsageMax_F32()); + delay(500); + } diff --git a/keywords.txt b/keywords.txt index cf11ee2..1bee52d 100644 --- a/keywords.txt +++ b/keywords.txt @@ -19,6 +19,7 @@ setXAxis KEYWORD2 AudioAnalyzeFFT1024_F32 KEYWORD1 AudioAnalyzeFFT2048_F32 KEYWORD1 AudioAnalyzeFFT4096_F32 KEYWORD1 +AudioAnalyzeFFT4096_IQEM_F32 KEYWORD1 AudioAnalyzePeak_F32 KEYWORD1 readPeakToPeak KEYWORD2