wirtz
/
OpenAudio_ArduinoLibrary
mirror of https://github.com/chipaudette/OpenAudio_ArduinoLibrary.git
1
0
Fork 0
Code Issues Releases Wiki Activity

Included averaging in analyze_fft1024_F32 (real input)

Browse Source
pull/6/merge
boblark 4 years ago
parent 822701e4a4
commit 319fa42626
3 changed files with 143 additions and 86 deletions
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Show Stats Download Patch File Download Diff File
  1. 82
      analyze_fft1024_F32.cpp
  2. 79
      analyze_fft1024_F32.h
  3. 68
      examples/TestFFT1024/TestFFT1024.ino

82
analyze_fft1024_F32.cpp
Unescape View File

@ -31,15 +31,15 @@
#include <Arduino.h> #include <Arduino.h>
#include "analyze_fft1024_F32.h" #include "analyze_fft1024_F32.h"
// #include "utility/dspinst.h"
// Move audio data from an audio_block_f32_t to the FFT instance buffer. // Move audio data from an audio_block_f32_t to the FFT instance buffer.
// This is for 128 numbers per block
static void copy_to_fft_buffer(void *destination, const void *source) static void copy_to_fft_buffer(void *destination, const void *source)
{ {
const float *src = (const float *)source; const float *src = (const float *)source;
float *dst = (float *)destination; float *dst = (float *)destination;
for (int i=0; i < AUDIO_BLOCK_SAMPLES; i++) { for (int i=0; i < 128; i++) {
*dst++ = *src++; // real sample *dst++ = *src++; // real sample
*dst++ = 0.0f; // 0 for Imag *dst++ = 0.0f; // 0 for Imag
} }
@ -51,17 +51,18 @@ static void apply_window_to_fft_buffer(void *buffer, const void *window)
const float *win = (float *)window; const float *win = (float *)window;
for (int i=0; i < 1024; i++) for (int i=0; i < 1024; i++)
buf[2*i] *= *win++; buf[2*i] *= *win++;
} }
void AudioAnalyzeFFT1024_F32::update(void) void AudioAnalyzeFFT1024_F32::update(void) {
{
audio_block_f32_t *block; audio_block_f32_t *block;
block = receiveReadOnly_f32(); uint32_t tt;
block = AudioStream_F32::receiveReadOnly_f32();
if (!block) return; if (!block) return;
// What all does 7EM cover?? // tt=micros();
#if defined(__ARM_ARCH_7EM__)
switch (state) { switch (state) {
case 0: case 0:
blocklist[0] = block; blocklist[0] = block;
@ -93,44 +94,69 @@ void AudioAnalyzeFFT1024_F32::update(void)
break; break;
case 7: case 7:
blocklist[7] = block; blocklist[7] = block;
// We have 4 previous blocks pointed to by blocklist[]:
copy_to_fft_buffer(fft_buffer+0x000, blocklist[0]->data); copy_to_fft_buffer(fft_buffer+0x000, blocklist[0]->data);
copy_to_fft_buffer(fft_buffer+0x100, blocklist[1]->data); copy_to_fft_buffer(fft_buffer+0x100, blocklist[1]->data);
copy_to_fft_buffer(fft_buffer+0x200, blocklist[2]->data); copy_to_fft_buffer(fft_buffer+0x200, blocklist[2]->data);
copy_to_fft_buffer(fft_buffer+0x300, blocklist[3]->data); copy_to_fft_buffer(fft_buffer+0x300, blocklist[3]->data);
// and 4 new blocks, just gathered:
copy_to_fft_buffer(fft_buffer+0x400, blocklist[4]->data); copy_to_fft_buffer(fft_buffer+0x400, blocklist[4]->data);
copy_to_fft_buffer(fft_buffer+0x500, blocklist[5]->data); copy_to_fft_buffer(fft_buffer+0x500, blocklist[5]->data);
copy_to_fft_buffer(fft_buffer+0x600, blocklist[6]->data); copy_to_fft_buffer(fft_buffer+0x600, blocklist[6]->data);
copy_to_fft_buffer(fft_buffer+0x700, blocklist[7]->data); copy_to_fft_buffer(fft_buffer+0x700, blocklist[7]->data);
if (pWin) if (pWin)
apply_window_to_fft_buffer(fft_buffer, window); apply_window_to_fft_buffer(fft_buffer, window);
#if defined(__IMXRT1062__)
// 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)
arm_cfft_f32 (&Sfft, fft_buffer, 0, 1);
#else
// For T3.x go back to old (deprecated) style
arm_cfft_radix4_f32(&fft_inst, fft_buffer); arm_cfft_radix4_f32(&fft_inst, fft_buffer);
#endif
count++; // Next do non-coherent averaging
for (int i=0; i < 512; i++) { for (int i=0; i < 512; i++) {
float magsq = fft_buffer[2*i]*fft_buffer[2*i] + fft_buffer[2*i+1]*fft_buffer[2*i+1]; float magsq = fft_buffer[2*i]*fft_buffer[2*i] + fft_buffer[2*i+1]*fft_buffer[2*i+1];
if(outputType==FFT_RMS) if(count==1) // Starting new average
output[i] = sqrtf(magsq); sumsq[i] = magsq;
else if(outputType==FFT_POWER) else if (count<=nAverage) // Adding on to average
output[i] = magsq; sumsq[i] += magsq;
else if(outputType==FFT_DBFS) }
output[i] = 10.0f*log10f(magsq)-54.1854f; // Scaled to FS sine wave if (count >= nAverage) { // Average is finished
else count = 0;
output[i] = 0.0f; float inAf = 1.0f/(float)nAverage;
} for(int i=0; i<512; i++) {
outputflag = true; if(outputType==FFT_RMS)
release(blocklist[0]); output[i] = sqrtf(inAf*sumsq[i]);
release(blocklist[1]); else if(outputType==FFT_POWER)
release(blocklist[2]); output[i] = inAf*sumsq[i];
release(blocklist[3]); else if(outputType==FFT_DBFS) {
if(sumsq[i]>0.0f)
output[i] = 10.0f*log10f(inAf*sumsq[i])-54.1854f; // Scaled to FS sine wave
else
output[i] = -193.0f; // lsb for 23 bit mantissa
}
else
output[i] = 0.0f;
} // End, set output[i] over all 512
outputflag = true;
} // End of average is finished
AudioStream_F32::release(blocklist[0]);
AudioStream_F32::release(blocklist[1]);
AudioStream_F32::release(blocklist[2]);
AudioStream_F32::release(blocklist[3]);
blocklist[0] = blocklist[4]; blocklist[0] = blocklist[4];
blocklist[1] = blocklist[5]; blocklist[1] = blocklist[5];
blocklist[2] = blocklist[6]; blocklist[2] = blocklist[6];
blocklist[3] = blocklist[7]; blocklist[3] = blocklist[7];
state = 4; state = 4;
break; break;
} } // End switch(state)
#else // Serial.print("uSec: "); Serial.println(micros()-tt);
release(block); } // End update()
#endif
}

79
analyze_fft1024_F32.h
Unescape View File

@ -32,7 +32,7 @@
* Power or dBFS (full scale). Output can be bin by bin or a pointer to * 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 * the output array is available. Several window functions are provided by
* in-class design, or a custom window can be provided from the INO. * in-class design, or a custom window can be provided from the INO.
* *
* Functions (See comments below and #defines above: * Functions (See comments below and #defines above:
* bool available() * bool available()
* float read(unsigned int binNumber) * float read(unsigned int binNumber)
@ -43,14 +43,15 @@
* float* getWindow(void) * float* getWindow(void)
* void putWindow(float *pwin) * void putWindow(float *pwin)
* void setOutputType(int _type) * void setOutputType(int _type)
* * void setNAverage(int nAverage)
*
* Timing, max is longest update() time: * Timing, max is longest update() time:
* T3.6 Windowed, RMS out, 1016 uSec max * T3.6 Windowed, Power Out, 975 uSec
* T3.6 Windowed, Power Out, 975 uSec max * T3.6 Windowed, RMS out, 1016 uSec
* T3.6 Windowed, dBFS out, 1591 uSec max * T3.6 Windowed, dBFS out, 1591 uSec
* No Window saves 60 uSec on T3.6 for any output. * No Window saves 60 uSec on T3.6 for any output.
* T4.0 Windowed, RMS Out, 149 uSec * T4.0 Windowed, Ave=1, Power Out, 156 uSec
* * T4.0 Windowed, Ave=1, dBFS Out, 302 uSec
* Scaling: * Scaling:
* Full scale for floating point DSP is a nebulous concept. Normally the * Full scale for floating point DSP is a nebulous concept. Normally the
* full scale is -1.0 to +1.0. This is an unscaled FFT and for a sine * full scale is -1.0 to +1.0. This is an unscaled FFT and for a sine
@ -62,7 +63,7 @@
* no matter how it is scaled, but this factor needs to be considered * no matter how it is scaled, but this factor needs to be considered
* when building the INO. * when building the INO.
*/ */
// Fixed float/int problem in read(first, last). RSL 3 Mar 21 // Fixed float/int problem in read(first, last). RSL 3 Mar 21
#ifndef analyze_fft1024_F32_h_ #ifndef analyze_fft1024_F32_h_
#define analyze_fft1024_F32_h_ #define analyze_fft1024_F32_h_
@ -71,6 +72,9 @@
#include "AudioStream_F32.h" #include "AudioStream_F32.h"
#include "arm_math.h" #include "arm_math.h"
#include "mathDSP_F32.h" #include "mathDSP_F32.h"
#if defined(__IMXRT1062__)
#include "arm_const_structs.h"
#endif
#define FFT_RMS 0 #define FFT_RMS 0
#define FFT_POWER 1 #define FFT_POWER 1
@ -84,25 +88,37 @@
class AudioAnalyzeFFT1024_F32 : public AudioStream_F32 { class AudioAnalyzeFFT1024_F32 : public AudioStream_F32 {
//GUI: inputs:1, outputs:0 //this line used for automatic generation of GUI node //GUI: inputs:1, outputs:0 //this line used for automatic generation of GUI node
//GUI: shortName:AnalyzeFFT1024 //GUI: shortName:FFT1024
public: public:
AudioAnalyzeFFT1024_F32() : AudioStream_F32(1, inputQueueArray) { AudioAnalyzeFFT1024_F32() : AudioStream_F32(1, inputQueueArray) {
arm_cfft_radix4_init_f32(&fft_inst, 1024, 0, 1); // __MK20DX128__ T_LC; __MKL26Z64__ T3.0; __MK20DX256__T3.1 and T3.2
useHanningWindow(); // Revisit this for more flexibility <<<<< // __MK64FX512__) T3.5; __MK66FX1M0__ T3.6; __IMXRT1062__ T4.0 and T4.1
#if defined(__IMXRT1062__)
// Teensy4 core library has the right files for new FFT
// arm CMSIS library has predefined structures of type arm_cfft_instance_f32
Sfft = arm_cfft_sR_f32_len1024; // This is one of the structures
#else
arm_cfft_radix4_init_f32(&fft_inst, 1024, 0, 1); // for T3.x
#endif
// This is always 128 block size. Any sample rate. No use of "setings"
// Bob: Revisit this to use CMSIS fast fft in place of cfft. faster?
useHanningWindow();
} }
// Inform that the output is available for read()
bool available() { bool available() {
if (outputflag == true) { if (outputflag == true) {
outputflag = false; outputflag = false;
return true; return true;
} }
return false; return false;
} }
// Output data from a single bin is transferred
float read(unsigned int binNumber) { float read(unsigned int binNumber) {
if (binNumber>511 || binNumber<0) return 0.0; if (binNumber>511 || binNumber<0) return 0.0;
return output[binNumber]; return output[binNumber];
} }
// Return sum of several bins. Normally use with power output. // Return sum of several bins. Normally use with power output.
// This produces the equivalent of bigger bins. // This produces the equivalent of bigger bins.
@ -147,8 +163,8 @@ public:
return 0; return 0;
} }
// Fast pointer transfer. Be aware that the data will go away // Fast pointer transfer. Be aware that the data will go away
// after the next 512 data points occur. // after the next 512 data points occur.
float* getData(void) { float* getData(void) {
return output; return output;
} }
@ -164,16 +180,22 @@ public:
for(int i=0; i<1024; i++) for(int i=0; i<1024; i++)
*p++ = *pwin++; *p++ = *pwin++;
} }
// Output RMS (default) Power or dBFS // Output RMS (default) Power or dBFS
void setOutputType(int _type) { void setOutputType(int _type) {
outputType = _type; outputType = _type;
} }
// Output power (non-coherent) averaging
void setNAverage(int _nAverage) {
nAverage = _nAverage;
}
virtual void update(void); virtual void update(void);
private: private:
float output[512]; float output[512];
float sumsq[512];
float window[1024]; float window[1024];
float *pWin = window; float *pWin = window;
audio_block_f32_t *blocklist[8]; audio_block_f32_t *blocklist[8];
@ -181,8 +203,16 @@ private:
uint8_t state = 0; uint8_t state = 0;
bool outputflag = false; bool outputflag = false;
audio_block_f32_t *inputQueueArray[1]; audio_block_f32_t *inputQueueArray[1];
arm_cfft_radix4_instance_f32 fft_inst; #if defined(__IMXRT1062__)
// For T4.x
// const static arm_cfft_instance_f32 arm_cfft_sR_f32_len1024;
arm_cfft_instance_f32 Sfft;
#else
arm_cfft_radix4_instance_f32 fft_inst;
#endif
int outputType = FFT_RMS; //Same type as I16 version init int outputType = FFT_RMS; //Same type as I16 version init
int nAverage = 1;
int count = 0; // used to average for nAverage of powers
// The Hann window is a good all-around window // The Hann window is a good all-around window
void useHanningWindow(void) { void useHanningWindow(void) {
@ -199,8 +229,8 @@ private:
float kx = 0.006141921; // 2*PI/1023 float kx = 0.006141921; // 2*PI/1023
int ix = (float) i; int ix = (float) i;
window[i] = 0.35875 - window[i] = 0.35875 -
0.48829*cosf( kx*ix) + 0.48829*cosf( kx*ix) +
0.14128*cosf(2.0f*kx*ix) - 0.14128*cosf(2.0f*kx*ix) -
0.01168*cosf(3.0f*kx*ix); 0.01168*cosf(3.0f*kx*ix);
} }
} }
@ -228,8 +258,7 @@ private:
xn2 = 0.00000382215877f*xn2*xn2; xn2 = 0.00000382215877f*xn2*xn2;
window[511 - n]=kbes*(mathEqualizer.i0f(beta*sqrtf(1.0-xn2))); window[511 - n]=kbes*(mathEqualizer.i0f(beta*sqrtf(1.0-xn2)));
window[512 + n] = window[511 - n]; window[512 + n] = window[511 - n];
}
} }
} };
};
#endif #endif

68
examples/TestFFT1024/TestFFT1024.ino
Unescape View File

@ -5,10 +5,11 @@
// on audio connected to the Left Line-In pin. By changing code, // on audio connected to the Left Line-In pin. By changing code,
// a synthetic sine wave can be input instead. // a synthetic sine wave can be input instead.
// //
// The first 40 (of 512) frequency analysis bins are printed to // The power output from 512 frequency analysis bins are printed to
// the Arduino Serial Monitor. // the Arduino Serial Monitor. The format is selectable.
// Output power averaging is an option
// //
// T4.0: Uses 6.1% processor and 9 F32 memory blocks, both max. // T4.0: Uses 11.5% processor and 9 F32 memory blocks, both max.
// //
// This example code is in the public domain. // This example code is in the public domain.
@ -25,13 +26,12 @@ const int myInput = AUDIO_INPUT_LINEIN;
AudioSynthSineCosine_F32 sinewave; AudioSynthSineCosine_F32 sinewave;
AudioAnalyzeFFT1024_F32 myFFT; AudioAnalyzeFFT1024_F32 myFFT;
AudioOutputI2S_F32 audioOutput; // audio shield: headphones & line-out NU AudioOutputI2S_F32 audioOutput; // audio shield: headphones & line-out NU
// Connect either the live input or synthesized sine wave // Connect either the live input or synthesized sine wave
// AudioConnection_F32 patchCord1(audioInput, 0, myFFT, 0); // AudioConnection_F32 patchCord1(audioInput, 0, myFFT, 0);
AudioConnection_F32 patchCord1(sinewave, 0, myFFT, 0); AudioConnection_F32 patchCord1(sinewave, 0, myFFT, 0);
AudioControlSGTL5000 audioShield;
AudioControlSGTL5000 audioShield; uint32_t ct = 0;
uint32_t count = 0; uint32_t count = 0;
void setup() { void setup() {
@ -45,50 +45,52 @@ void setup() {
audioShield.inputSelect(myInput); audioShield.inputSelect(myInput);
audioShield.volume(0.5); audioShield.volume(0.5);
// Create a synthetic sine wave, for testing
// To use this, edit the connections above
// sinewave.frequency(1033.99f); // Bin 24 T3.x
// sinewave.frequency(1033.59375f); // Bin 24 T4.x at 44100
// sinewave.frequency(1055.0f); // Bin 24.5, demonstrates windowing
sinewave.frequency(1076.0f);
sinewave.amplitude(1.0f);
// Set windowing function // Set windowing function
// myFFT.windowFunction(NULL); // myFFT.windowFunction(AudioWindowNone);
// myFFT.windowFunction(AudioWindowNone); // Same as NULL
// myFFT.windowFunction(AudioWindowHanning1024); // default // myFFT.windowFunction(AudioWindowHanning1024); // default
// The next Kaiser window needs a dB peak sidelobe number // The next Kaiser window needs a dB peak sidelobe number
myFFT.windowFunction(AudioWindowKaiser1024, 70.0f); // myFFT.windowFunction(AudioWindowKaiser1024, 70.0f);
// myFFT.windowFunction(AudioWindowBlackmanHarris1024); myFFT.windowFunction(AudioWindowBlackmanHarris1024);
// To print the window function: // To print the window function:
// float* pw=myFFT.getWindow(); // float* pw=myFFT.getWindow();
// for(int jj=0; jj<1024; jj++) // for(int jj=0; jj<1024; jj++)
// Serial.println(*pw++, 6); // Serial.println(*pw++, 6);
// Create a synthetic sine wave, for testing myFFT.setNAverage(1);
// To use this, edit the connections above
sinewave.frequency(1034.0); // Bin 24
// sinewave.frequency(1055.0f); // Bin 24.5, demonstrates windowing
myFFT.setOutputType(FFT_DBFS); // FFT_RMS or FFT_POWER or FFT_DBFS myFFT.setOutputType(FFT_DBFS); // FFT_RMS or FFT_POWER or FFT_DBFS
} }
void loop() { void loop() {
if (myFFT.available()) { if (myFFT.available() /*&& ++ct == 4*/ ) {
// each time new FFT data is available // each time new FFT data is available
// print it all to the Arduino Serial Monitor // print it all to the Arduino Serial Monitor
Serial.print("FFT: "); Serial.println("FFT Output: ");
for (int i=0; i<40; i++) { for (int i=0; i<512; i++) {
Serial.print(myFFT.read(i), 2); Serial.print(i);
Serial.print(","); Serial.print(",");
} Serial.println(myFFT.read(i), 3);
}
Serial.println(); Serial.println();
} }
/* if(count++ == 3000) { /*
Serial.print("CPU: Percent Usage, Max: "); if(count++<200) {
Serial.print(AudioProcessorUsage()); Serial.print("CPU: Max Percent Usage: ");
Serial.print(", ");
Serial.println(AudioProcessorUsageMax()); Serial.println(AudioProcessorUsageMax());
Serial.print(" Float 32 Memory: "); Serial.print(" Max Float 32 Memory: ");
Serial.print(AudioMemoryUsage_F32());
Serial.print(", ");
Serial.println(AudioMemoryUsageMax_F32()); Serial.println(AudioMemoryUsageMax_F32());
} }
delay(2); */
*/ delay(500);
} }

Write Preview
Loading…
Cancel
Save