kgoba-ft8_lib/common/audio.c

#include "audio.h"

#include <stdio.h>
#include <string.h>

#ifdef USE_PORTAUDIO
#include <portaudio.h>

typedef struct
{
    PaStream* instream;
} audio_context_t;

static audio_context_t audio_context;

static int audio_cb(void* inputBuffer, void* outputBuffer, unsigned long framesPerBuffer,
    const PaStreamCallbackTimeInfo* timeInfo, PaStreamCallbackFlags statusFlags, void* userData)
{
    audio_context_t* context = (audio_context_t*)userData;
    float* samples_in = (float*)inputBuffer;

    // PaTime time = data->startTime + timeInfo->inputBufferAdcTime;
    printf("Callback with %ld samples\n", framesPerBuffer);
    return 0;
}

void audio_list(void)
{
    PaError pa_rc;

    pa_rc = Pa_Initialize(); // Initialize PortAudio
    if (pa_rc != paNoError)
    {
        printf("Error initializing PortAudio.\n");
        printf("\tErrortext: %s\n\tNumber: %d\n", Pa_GetErrorText(pa_rc), pa_rc);
        return;
    }

    int numDevices;
    numDevices = Pa_GetDeviceCount();
    if (numDevices < 0)
    {
        printf("ERROR: Pa_CountDevices returned 0x%x\n", numDevices);
        return;
    }

    printf("%d audio devices found:\n", numDevices);
    for (int i = 0; i < numDevices; i++)
    {
        const PaDeviceInfo* deviceInfo = Pa_GetDeviceInfo(i);

        PaStreamParameters inputParameters = {
            .device = i,
            .channelCount = 1, // 1 = mono, 2 = stereo
            .sampleFormat = paFloat32,
            .suggestedLatency = 0.2,
            .hostApiSpecificStreamInfo = NULL
        };
        double sample_rate = 12000; // sample rate (frames per second)
        pa_rc = Pa_IsFormatSupported(&inputParameters, NULL, sample_rate);

        printf("%d: [%s] [%s]\n", (i + 1), deviceInfo->name, (pa_rc == paNoError) ? "OK" : "NOT SUPPORTED");
    }
}

int audio_init(void)
{
    PaError pa_rc;

    pa_rc = Pa_Initialize(); // Initialize PortAudio
    if (pa_rc != paNoError)
    {
        printf("Error initializing PortAudio.\n");
        printf("\tErrortext: %s\n\tNumber: %d\n", Pa_GetErrorText(pa_rc), pa_rc);
        Pa_Terminate(); // I don't think we need this but...
        return -1;
    }
    return 0;
}

int audio_open(const char* name)
{
    PaError pa_rc;
    audio_context.instream = NULL;

    PaDeviceIndex ndevice_in = -1;
    int numDevices = Pa_GetDeviceCount();
    for (int i = 0; i < numDevices; i++)
    {
        const PaDeviceInfo* deviceInfo = Pa_GetDeviceInfo(i);
        if (0 == strcmp(deviceInfo->name, name))
        {
            ndevice_in = i;
            break;
        }
    }

    if (ndevice_in < 0)
    {
        printf("Could not find device [%s].\n", name);
        audio_list();
        return -1;
    }

    unsigned long nfpb = 1920 / 4; // frames per buffer
    double sample_rate = 12000;    // sample rate (frames per second)

    PaStreamParameters inputParameters = {
        .device = ndevice_in,
        .channelCount = 1, // 1 = mono, 2 = stereo
        .sampleFormat = paFloat32,
        .suggestedLatency = 0.2,
        .hostApiSpecificStreamInfo = NULL
    };

    // Test if this configuration actually works, so we do not run into an ugly assertion
    pa_rc = Pa_IsFormatSupported(&inputParameters, NULL, sample_rate);
    if (pa_rc != paNoError)
    {
        printf("Error opening input audio stream.\n");
        printf("\tErrortext: %s\n\tNumber: %d\n", Pa_GetErrorText(pa_rc), pa_rc);
        return -2;
    }

    PaStream* instream;
    pa_rc = Pa_OpenStream(
        &instream, // address of stream
        &inputParameters,
        NULL,
        sample_rate, // Sample rate
        nfpb,        // Frames per buffer
        paNoFlag,
        NULL /*(PaStreamCallback*)audio_cb*/, // Callback routine
        NULL /*(void*)&audio_context*/);      // address of data structure
    if (pa_rc != paNoError)
    { // We should have no error here usually
        printf("Error opening input audio stream:\n");
        printf("\tErrortext: %s\n\tNumber: %d\n", Pa_GetErrorText(pa_rc), pa_rc);
        return -3;
    }
    // printf("Successfully opened audio input.\n");

    pa_rc = Pa_StartStream(instream); // Start input stream
    if (pa_rc != paNoError)
    {
        printf("Error starting input audio stream!\n");
        printf("\tErrortext: %s\n\tNumber: %d\n", Pa_GetErrorText(pa_rc), pa_rc);
        return -4;
    }

    audio_context.instream = instream;

    // while (Pa_IsStreamActive(instream))
    // {
    //     Pa_Sleep(100);
    // }
    // Pa_AbortStream(instream); // Abort stream
    // Pa_CloseStream(instream); // Close stream, we're done.

    return 0;
}

int audio_read(float* buffer, int num_samples)
{
    PaError pa_rc;
    pa_rc = Pa_ReadStream(audio_context.instream, (void*)buffer, num_samples);
    return 0;
}

#else

int audio_init(void)
{
    return -1;
}

void audio_list(void)
{
}

int audio_open(const char* name)
{
    return -1;
}

int audio_read(float* buffer, int num_samples)
{
    return -1;
}

#endif