How Can I apply resample to this custom generator signal? Thanks in advanced

[hash6iron]

I have code a function to generate square signal to put directly to i2s buffer. This function works fine. I'd like to apply resample to this signal. How can I do it? Thanks in advance.

void createTestSignal(uint8_t *buffer, int samples, int amplitude)
{
            int chn = channels;
            size_t result = 0;
            int16_t *ptr = (int16_t*)buffer;
            int16_t sample_L = amplitude;
            int16_t sample_R = amplitude;

            for (int j=0;j<samples;j++)
            {
                //R-OUT
                *ptr++ = sample_R;
                //L-OUT
                *ptr++ = sample_L;
                result+=2*chn;
            }   
            
            // m_kit is a global Audiokit variable configure to output audio 
            // at 44100Hz, 16bits and 2 channels with Audiokit board with ES8388 codec chip
            m_kit(buffer,result);
     
 }

[pschatzmann]

This info can be found in the Wiki. Just read the Introduction and the Format Change Wikis

[hash6iron]

Ok thanks.

[hash6iron]

@pschatzmann ,

I have this code below according to I could understand reading the wiki, but how can I solve the int16_t type error to adapt my array buffer (signal) to Stream?

        void samplingtest(float samplingrate)
        {
           
            AudioInfo info(44100, 2, 16);
            int totalSamples = 44100;
            uint8_t buffer[totalSamples*2*channels];
            int16_t *samples = (int16_t*) buffer;

            size_t ssignal = createTestSignal(buffer,ss,30000);

            GeneratorFromArray<int16_t> signal((int16_t)buffer,0,false);   // Here there is a type error

            GeneratedSoundStream<int16_t> in(signal);
            in.begin(info);

            size_t bytes_read = in.readBytes(buffer, 1024);
            size_t samples_read = bytes_read/sizeof(int16_t);            
        }

[pschatzmann]

You would just write your samples to a ResampleStream which would be connected to an I2SStream.

ResampleStream out(m_kit);
out.write((uint8_t*)&sample_L, sizeof(int16_t);
out.write((uint8_t*)&sample_R, sizeof(int16_t);

Maybe you need to fill an array first, so that the resampler has more then 1 data point to work with...

[hash6iron]

Is possible to use AudioKit instead of AudiokitStream? All my code uses AudioKit as board.

[pschatzmann]

This is obsolete: use the new functionality!

[hash6iron]

Is compatible AudioKit with I2SCodecStream? I'd need do a hard refactor.

I try to declare I2SCodecStream but VSCode say me. "error: 'ESP32kit' was not declared in this scope"

I2SCodecStream ESP32kit(AudioKitEs8388V2);