improved ADCsample processing (from SR WLED)

improved ADCsample processing,  including replacement of "rogue" samples from other channels (this happens at least once in 5 seconds !!).

It compiles, don't ship it yet - needs more testing.
This commit is contained in:
Frank 2022-08-14 16:17:34 +02:00
parent c6691564a5
commit 5a4713950c

View File

@ -339,6 +339,7 @@ class I2SAdcSource : public I2SSource {
AudioSourceType getType(void) {return(Type_I2SAdc);}
void initialize(int8_t audioPin, int8_t = I2S_PIN_NO_CHANGE, int8_t = I2S_PIN_NO_CHANGE, int8_t = I2S_PIN_NO_CHANGE, int8_t = I2S_PIN_NO_CHANGE, int8_t = I2S_PIN_NO_CHANGE) {
_myADCchannel = 0x0F;
if(!pinManager.allocatePin(audioPin, false, PinOwner::UM_Audioreactive)) {
DEBUGSR_PRINTF("failed to allocate GPIO for audio analog input: %d\n", audioPin);
return;
@ -352,6 +353,7 @@ class I2SAdcSource : public I2SSource {
return;
} else {
adc_gpio_init(ADC_UNIT_1, adc_channel_t(channel));
_myADCchannel = channel;
}
// Install Driver
@ -368,60 +370,114 @@ class I2SAdcSource : public I2SSource {
return;
}
// adc1_config_channel_atten(adc1_channel_t(channel), ADC_ATTEN_DB_11)); //see https://github.com/espressif/arduino-esp32/blob/master/libraries/ESP32/examples/I2S/HiFreq_ADC/HiFreq_ADC.ino
#if defined(ARDUINO_ARCH_ESP32)
#if defined(I2S_GRAB_ADC1_COMPLETELY)
// according to docs from espressif, the ADC needs to be started explicitly
// fingers crossed
err = i2s_adc_enable(I2S_NUM_0);
if (err != ESP_OK) {
DEBUGSR_PRINTF("Failed to enable i2s adc: %d\n", err);
//return;
}
#endif
err = i2s_adc_enable(I2S_NUM_0);
if (err != ESP_OK) {
DEBUGSR_PRINTF("Failed to enable i2s adc: %d\n", err);
//return;
}
#else
err = i2s_adc_disable(I2S_NUM_0);
//err = i2s_stop(I2S_NUM_0);
if (err != ESP_OK) {
DEBUGSR_PRINTF("Failed to initially disable i2s adc: %d\n", err);
}
#endif
_initialized = true;
}
I2S_datatype postProcessSample(I2S_datatype sample_in) {
static I2S_datatype lastADCsample = 0; // last good sample
static unsigned int broken_samples_counter = 0; // number of consecutive broken (and fixed) ADC samples
I2S_datatype sample_out = 0;
// bring sample down down to 16bit unsigned
I2S_unsigned_datatype rawData = * reinterpret_cast<I2S_unsigned_datatype *> (&sample_in); // C++ acrobatics to get sample as "unsigned"
#ifndef I2S_USE_16BIT_SAMPLES
rawData = (rawData >> 16) & 0xFFFF; // scale input down from 32bit -> 16bit
I2S_datatype lastGoodSample = lastADCsample / 16384 ; // prepare "last good sample" accordingly (26bit-> 12bit with correct sign handling)
#else
rawData = rawData & 0xFFFF; // input is already in 16bit, just mask off possible junk
I2S_datatype lastGoodSample = lastADCsample * 4; // prepare "last good sample" accordingly (10bit-> 12bit)
#endif
// decode ADC sample data fields
uint16_t the_channel = (rawData >> 12) & 0x000F; // upper 4 bit = ADC channel
uint16_t the_sample = rawData & 0x0FFF; // lower 12bit -> ADC sample (unsigned)
I2S_datatype finalSample = (int(the_sample) - 2048); // convert unsigned sample to signed (centered at 0);
if ((the_channel != _myADCchannel) && (_myADCchannel != 0x0F)) { // 0x0F means "don't know what my channel is"
// fix bad sample
finalSample = lastGoodSample; // replace with last good ADC sample
broken_samples_counter ++;
if (broken_samples_counter > 256) _myADCchannel = 0x0F; // too many bad samples in a row -> disable sample corrections
//Serial.print("\n!ADC rogue sample 0x"); Serial.print(rawData, HEX); Serial.print("\tchannel:");Serial.println(the_channel);
} else broken_samples_counter = 0; // good sample - reset counter
// back to original resolution
#ifndef I2S_USE_16BIT_SAMPLES
finalSample = finalSample << 16; // scale up from 16bit -> 32bit;
#endif
finalSample = finalSample / 4; // mimic old analog driver behaviour (12bit -> 10bit)
sample_out = (3 * finalSample + lastADCsample) / 4; // apply low-pass filter (2-tap FIR)
//sample_out = (finalSample + lastADCsample) / 2; // apply stronger low-pass filter (2-tap FIR)
lastADCsample = sample_out; // update ADC last sample
return(sample_out);
}
void getSamples(float *buffer, uint16_t num_samples) {
/* Enable ADC. This has to be enabled and disabled directly before and
* after sampling, otherwise Wifi dies
*/
if (_initialized) {
#if !defined(ARDUINO_ARCH_ESP32)
// old code - works for me without enable/disable, at least on ESP32.
esp_err_t err = i2s_adc_enable(I2S_NUM_0);
//esp_err_t err = i2s_start(I2S_NUM_0);
if (err != ESP_OK) {
DEBUGSR_PRINTF("Failed to enable i2s adc: %d\n", err);
return;
}
#endif
#if !defined(I2S_GRAB_ADC1_COMPLETELY)
// old code - works for me without enable/disable, at least on ESP32.
//esp_err_t err = i2s_start(I2S_NUM_0);
esp_err_t err = i2s_adc_enable(I2S_NUM_0);
if (err != ESP_OK) {
DEBUGSR_PRINTF("Failed to enable i2s adc: %d\n", err);
return;
}
#endif
I2SSource::getSamples(buffer, num_samples);
#if !defined(ARDUINO_ARCH_ESP32)
// old code - works for me without enable/disable, at least on ESP32.
err = i2s_adc_disable(I2S_NUM_0); //i2s_adc_disable() may cause crash with IDF 4.4 (https://github.com/espressif/arduino-esp32/issues/6832)
//err = i2s_stop(I2S_NUM_0);
if (err != ESP_OK) {
DEBUGSR_PRINTF("Failed to disable i2s adc: %d\n", err);
return;
}
#endif
#if !defined(I2S_GRAB_ADC1_COMPLETELY)
// old code - works for me without enable/disable, at least on ESP32.
err = i2s_adc_disable(I2S_NUM_0); //i2s_adc_disable() may cause crash with IDF 4.4 (https://github.com/espressif/arduino-esp32/issues/6832)
//err = i2s_stop(I2S_NUM_0);
if (err != ESP_OK) {
DEBUGSR_PRINTF("Failed to disable i2s adc: %d\n", err);
return;
}
#endif
}
}
void deinitialize() {
pinManager.deallocatePin(_audioPin, PinOwner::UM_Audioreactive);
_initialized = false;
_myADCchannel = 0x0F;
esp_err_t err;
#if defined(ARDUINO_ARCH_ESP32)
// according to docs from espressif, the ADC needs to be stopped explicitly
// fingers crossed
err = i2s_adc_disable(I2S_NUM_0);
if (err != ESP_OK) {
DEBUGSR_PRINTF("Failed to disable i2s adc: %d\n", err);
//return;
}
#endif
#if defined(I2S_GRAB_ADC1_COMPLETELY)
// according to docs from espressif, the ADC needs to be stopped explicitly
// fingers crossed
err = i2s_adc_disable(I2S_NUM_0);
if (err != ESP_OK) {
DEBUGSR_PRINTF("Failed to disable i2s adc: %d\n", err);
}
#endif
i2s_stop(I2S_NUM_0);
err = i2s_driver_uninstall(I2S_NUM_0);
if (err != ESP_OK) {
DEBUGSR_PRINTF("Failed to uninstall i2s driver: %d\n", err);
@ -431,6 +487,7 @@ class I2SAdcSource : public I2SSource {
private:
int8_t _audioPin;
int8_t _myADCchannel = 0x0F; // current ADC channel for analog input. 0x0F means "undefined"
};
/* SPH0645 Microphone