changing pitch of audio samples - TeensyVariablePlayback library
- Thread starter Moo
- Start date
h4yn0nnym0u5e
Well-known member
Slightly surprised that you're surprised by the "audible interruptions", given that your audio file fades in at the start and out at the end, so there's about 0.5s of near-silence if it's looped without setting start and finish points.
Here's an edit of your code which works, as far as I can tell:
Here's an edit of your code which works, as far as I can tell:
C++:
#include <Arduino.h>
#include <Audio.h>
#include <SD.h>
#include <TeensyVariablePlayback.h>
// GUItool: begin automatically generated code
AudioPlaySdResmp playSdWav1; //xy=324,457
AudioOutputI2S i2s2; //xy=840.8571472167969,445.5714416503906
AudioConnection patchCord1(playSdWav1, 0, i2s2, 0);
AudioConnection patchCord2(playSdWav1, 0, i2s2, 1);
AudioControlSGTL5000 audioShield;
// GUItool: end automatically generated code
double getPlaybackRate(int16_t analog);
char* _filename = "SPACE.WAV";
void setup() {
Serial.begin(9600);
if (!(SD.begin(10))) {
// stop here if no SD card, but print a message
while (1) {
Serial.println("Unable to access the SD card");
delay(500);
}
}
AudioMemory(24);
audioShield.enable();
audioShield.volume(0.5);
playSdWav1.enableInterpolation(true);
playSdWav1.setPlaybackRate(1.0);
playSdWav1.playWav(_filename);
playSdWav1.setLoopType(looptype_repeat);
// Sound sample isn't seamless, so pick some loop points
playSdWav1.setLoopStart(19374);
playSdWav1.setLoopFinish(643346);
// Extra stuff to mask glitches at loop point
playSdWav1.setUseDualPlaybackHead(true);
playSdWav1.setCrossfadeDurationInSamples(1000);
}
float rate=1.0f, factor = 1.001f;
uint32_t next;
bool increasing;
void loop() {
int newsensorValue = analogRead(A0);
// I don't have a sensor, so just ramp rate up and down
if (millis() >= next)
{
next = millis() + 3; // every 3ms, i.e. roughly every audio update
if (increasing)
{
rate *= factor;
increasing = rate < 2.0f;
}
else
{
rate /= factor;
increasing = rate < 0.5f;
}
playSdWav1.setPlaybackRate(rate);
}
if(!playSdWav1.isPlaying()) {
Serial.println("Restarted playback"); // This Never Happens
playSdWav1.playWav(_filename);
}
}
// map analog input 0-1023 to 0.5-3.0 pitch
double getPlaybackRate(int16_t analog) { //analog: 0..1023
return ((analog / 1023) * 2.5) + 0.5;
}h4yn0nnym0u5e
Well-known member
Image of WAV file supplied, showing loop points I selected
Just wanted to report back that the code works. Thanks!
I removed the fade in Audacity, so I removed
setLoopStart() and setLoopFinish() aswell.When I extend the crossfade, the loop is almost inaudible.
h4yn0nnym0u5e
Well-known member
Good news. Nice to have some feedback from a Real User, even better when it results in an example to refer back to!
Hi @h4yn0nnym0u5e, I'm testing the array player, the pitch, loop type and crossfade works but not having luck with the start and end points of the loop, same with the setPlayStart (it always plays the whole sample starting at the beginning).
Could you confirm that these functions are also implemented for the array player?
here's the relevant part of my code. The variable audio_samples will be the size of the array audioBuffer/2
Could you confirm that these functions are also implemented for the array player?
here's the relevant part of my code. The variable audio_samples will be the size of the array audioBuffer/2
Code:
AudioPlayArrayResmp wave;
uint32_t audio_samples = 0;
wave.enableInterpolation(true);
wave.setUseDualPlaybackHead(true);
wave.setPlayStart(play_start_loop);
wave.setLoopType(looptype_pingpong);
void noteOn(uint8_t MIDInote, uint8_t MIDIvel, bool slide)
{
wave.playRaw(audio_buffer, audio_samples, 1); // 1 = mono
}
void setParam(uint8_t param, uint8_t val)
{
switch(param)
{
case setPitch:
wave.setPlaybackRate(pitch[val]);
break;
case setLoopStart:
wave.setLoopStart((audio_samples * val) / 127);
break;
case setLoopEnd:
wave.setLoopFinish((audio_samples * val) / 127);
break;
case setCrossfade:
wave.setCrossfadeDurationInSamples((audio_samples * val) / 127);
break;
}
}h4yn0nnym0u5e
Well-known member
Most functions are agnostic about the audio source (SD, array, etc.), as far as I know, though there may be exceptions - I didn't look too closely at anything other than SD (filesystem) playback.
One thing I do know is that the various
Further than that, it's hard to guess. If you can craft a small sketch requiring no hardware apart from a Teensy, audio adaptor of some sort, and a file to play, and where you can state specifically "at this point I expect to hear A, but what I get is B", then maybe I can help more.
One thing I do know is that the various
play() methods have a tendency to reset the loop start and end values, so you need to (re)set those after you start playback. (It's not an ideal API, but I wasn't about to change it since I didn't know how many existing applications would break as a result.) Your code fragment above suggests you're only setting them from MIDI values, without making a record of those settings that you can re-use in subsequent noteOn() calls.Further than that, it's hard to guess. If you can craft a small sketch requiring no hardware apart from a Teensy, audio adaptor of some sort, and a file to play, and where you can state specifically "at this point I expect to hear A, but what I get is B", then maybe I can help more.
h4yn0nnym0u5e
Well-known member
- Stop using the samples
- Free the PSRAM they’re in
- Allocate PSRAM for the new samples
- Load the samples into the allocated space
Rolfdegen
Well-known member
Load new Sample from file list. It works a few times but then my Teensy 4.1 with 16MB PSRAM is crashes (see Video)
Video
Video
C:
// stop all samples
for (size_t i = 0; i < 8; i++)
{
sampleOsc[i].stop();
}
// load new sample from list
String Folder = "Samples/";
String name_ = Folder + fileNames[new_index - 1]; // sample name from string list
char *_filename = const_cast<char*>(name_.c_str());
newdigate::flashloader loader;
Sample = loader.loadSample(_filename);
Last edited:
h4yn0nnym0u5e
Well-known member
flashloader isn't very good - it has no way of freeing up unused samples. And your posted code fragment doesn't even attempt to address my point 2 in post #236...
h4yn0nnym0u5e
Well-known member
No, it just creates an instance of the loader. You only need, and ideally should only have, one such instance in your entire program. It attempts (rather poorly...) to keep track of the amount of PSRAM used, but each instance has its own count.
I think it should be something like
C++:
extmem_free(Sample->sampledata);
delete Sample;
Sample = nullptr;It would be much better if that code had been a method provided by the flashloader class, of course. Once again, I’d say that flashloader is really so poor that it’s hardly worth the effort to understand and use it.
Rolfdegen
Well-known member
Thanks for your help. Loading samples now works without crashes (see my Video). I also made some changes to the flashloader.cpp file. As an example, I used the psramloader.cpp from MicroDexed-touch.
new flashloader.cpp
load sample from file list
Video
new flashloader.cpp
C:
// new flashloader.cpp
#include "flashloader.h"
#include <Audio.h>
namespace newdigate {
audiosample * flashloader::loadSample(const char *filename ) {
uint8_t *data = nullptr;
Serial.printf("Reading %s\n", filename);
File f = SD.open(filename, O_READ);
if (f) {
if (f.size() < _bytesavailable) {
//noInterrupts();
AudioNoInterrupts();
uint32_t total_read = 0;
//auto *data = (int8_t*)extmem_malloc(f.size() );
data = (uint8_t*)extmem_malloc(f.size());
uint8_t *index = data;
while (f.available()) {
size_t bytesRead = f.read(index, flashloader_default_sd_buffersize);
if (bytesRead == 0)
break;
total_read += bytesRead;
index += bytesRead;
}
//interrupts();
AudioInterrupts();
_bytesavailable -= total_read;
audiosample *sample = new audiosample();
sample->sampledata = (int16_t*)data;
sample->samplesize = f.size();
Serial.printf("\tsample start %x\n", (uint32_t)data);
Serial.printf("\tsample size %d\n", sample->samplesize);
Serial.printf("\tavailable: %d\n", _bytesavailable);
return sample;
}
}
Serial.printf("not found %s\n", filename);
return nullptr;
}
}load sample from file list
C:
// press patch list on page1 -----------------------------------
void press_patch_list_page1()
{
uint8_t new_index = 0;
static uint8_t old_index = 0;
static uint8_t old_key_index = 1;
new_index = touch_patch_list();
if (new_index != old_index)
{
old_index = new_index;
if (new_index >= 1 && new_index <= 7)
{
if (new_index != old_key_index)
{
old_key_index = new_index;
sample_busy_flag = false;
extmem_free(Sample->sampledata);
//delete Sample;
Sample = nullptr;
print_file_List(new_index - 1);
tft.updateScreenAsync(false); // draw screen
// stop all samples
for (size_t i = 0; i < 8; i++)
{
sampleOsc[i].stop();
}
String Folder = "Samples/";
String name_ = Folder + fileNames[new_index - 1]; // sample name from string list
char *_filename = const_cast<char*>(name_.c_str());
Sample = loader.loadSample(_filename);
sample_busy_flag = true;
}
}
else if (new_index == 0)
{
for (size_t i = 0; i < 7; i++)
{
TK_state_List_P1[i] = false; // clear touch state
}
}
}
if (new_index > 0)
{
Reset_screensaver();
}
}Video
h4yn0nnym0u5e
Well-known member
Because of
you need to un-comment
or you will have a slow memory leak…
C++:
audiosample *sample = new audiosample();
C++:
//delete Sample;Rolfdegen
Well-known member
When loading larger samples > 1MB there are random crashes 
C:
#ifndef PSRAMLOADER_H
#define PSRAMLOADER_H
#include <Arduino.h>
#include <SD.h>
extern "C" uint8_t external_psram_size;
namespace newdigate {
const uint32_t flashloader_default_sd_buffersize = 4 * 1024;
struct audiosample {
int16_t *sampledata;
uint32_t samplesize;
};
class Psramloader {
public:
Psramloader() {
_bytesavailable = external_psram_size * 1048576;
}
uint32_t _bytesavailable = 0;
audiosample * loadSample(const char *filename);
};
};
#endif
C:
#include "psramloader.h"
#include <Audio.h>
namespace newdigate {
audiosample * Psramloader::loadSample(const char *filename ) {
uint8_t *data = nullptr;
Serial.printf("Reading %s\n", filename);
File f = SD.open(filename, O_READ);
if (f) {
if (f.size() < _bytesavailable) {
AudioNoInterrupts();
uint32_t total_read = 0;
data = (uint8_t*)extmem_malloc(f.size());
uint8_t *index = data;
while (f.available()) {
size_t bytesRead = f.read(index, flashloader_default_sd_buffersize);
if (bytesRead == 0)
break;
total_read += bytesRead;
index += bytesRead;
}
AudioInterrupts();
_bytesavailable -= total_read;
audiosample *sample = new audiosample();
sample->sampledata = (int16_t*)data;
sample->samplesize = f.size();
Serial.printf("\tsample start %x\n", (uint32_t)data);
Serial.printf("\tsample size %d\n", sample->samplesize);
Serial.printf("\tavailable: %d\n", _bytesavailable);
return sample;
}
}
Serial.printf("not found %s\n", filename);
return nullptr;
}
}
Last edited:
h4yn0nnym0u5e
Well-known member
Have you used CrashReport to try to find out where the crash is occurring? Does the synth have to be playing, or will it crash if you just keep loading different big samples?
I just noticed your code in post #241 only stops playing after freeing the sample memory, which is not the correct order given in my post #236.
I just noticed your code in post #241 only stops playing after freeing the sample memory, which is not the correct order given in my post #236.
h4yn0nnym0u5e
Well-known member
h4yn0nnym0u5e
Well-known member
Really? It doesn’t look much like it…
…it looks like you still have a slightly modified copy of the original newdigate code. Which as I’ve repeatedly said, is not fit for serious use!
The MicroDexed-touch code has an
unloadSample method that keeps track of PSRAM memory that it has consumed. Though it may or may not keep track of memory allocated by other modules - I haven’t looked very closely at the source code. You could probably adopt it, with changes, if you don’t use PSRAM for anything other than samples. But it looks a bit specific to the Microdexed-touch … it would probably be easier to write your own code from scratch.