public int SDL_Init()
{
Callback = SDL_AudioCallback;
#region SDL调用
//// 初始化调用SDL.SDL_Init(SDL.SDL_INIT_VIDEO | SDL.SDL_INIT_AUDIO | SDL.SDL_INIT_TIMER)
//if (SDL.SDL_Init(SDL.SDL_INIT_VIDEO | SDL.SDL_INIT_AUDIO | SDL.SDL_INIT_TIMER) < 0)
//{
// Console.WriteLine("Could not initialize SDL - {0}\n", SDL.SDL_GetError());
// return -1;
//}
#endregion
SDL.SDL_AudioSpec wanted_spec = new SDL.SDL_AudioSpec();
wanted_spec.freq = 8000;
wanted_spec.format = SDL.AUDIO_S16;
wanted_spec.channels = 1;
wanted_spec.silence = 0;
wanted_spec.samples = 320;
wanted_spec.callback = Callback;
if (SDL.SDL_OpenAudio(ref wanted_spec, out SDL.SDL_AudioSpec obtained) < 0)
{
Console.WriteLine("can't open audio.");
return(-1);
}
//Play
SDL.SDL_PauseAudio(0);
return(0);
}
public int SDL_Init(AVCodecContext *audioCtx)
{
Callback = SDL_AudioCallback;
SDL.SDL_AudioSpec wanted_spec = new SDL.SDL_AudioSpec();
wanted_spec.freq = audioCtx->sample_rate;
wanted_spec.format = SDL.AUDIO_F32;
wanted_spec.channels = (byte)audioCtx->channels;
wanted_spec.silence = 0;
wanted_spec.samples = 1024;
wanted_spec.callback = Callback;
if (SDL.SDL_OpenAudio(ref wanted_spec, IntPtr.Zero) < 0)
{
Console.WriteLine("can't open audio.");
return(-1);
}
//Play
SDL.SDL_PauseAudio(0);
return(0);
}
public AudioEngine(string audioDevice = null, AudioDriver driver = AudioDriver.Default, int sampleRate = 44100, int bufferLength = 1024, ResampleQuality resampleQuality = ResampleQuality.High)
{
this.resampleQuality = resampleQuality;
SDL.SDL_InitSubSystem(SDL.SDL_INIT_AUDIO);
audioCallback = AudioCallback;
SDL.SDL_AudioSpec desired = new SDL.SDL_AudioSpec()
{
freq = sampleRate,
format = SDL.AUDIO_S16,
channels = 2,
samples = (ushort)bufferLength,
callback = audioCallback,
};
if (driver == AudioDriver.File)
{
audioSpec = desired;
audioDriver = driver;
}
else
{
string[] audioDrivers = new string[SDL.SDL_GetNumAudioDrivers()];
for (int i = 0; i < audioDrivers.Length; i++)
{
audioDrivers[i] = SDL.SDL_GetAudioDriver(i);
}
string driverName = audioDrivers[0];
string driverFallbackName = audioDrivers.Length > 1 ? audioDrivers[1] : null;
if (driver != AudioDriver.Default)
{
driverName = driver.ToString();
}
int init = SDL.SDL_AudioInit(driverName.ToLower());
if (init != 0 && driverName == AudioDriver.XAudio2.ToString().ToLower() && driverFallbackName != null)
{
// supplied SDL.dll does not support XAudio2, fallback to next driver
driverName = driverFallbackName;
init = SDL.SDL_AudioInit(driverName.ToLower());
}
if (init != 0)
{
throw new ApplicationException("Failed to initialize audio driver " + driverName + ": " + SDL.SDL_GetError());
}
Enum.TryParse(driverName, true, out audioDriver);
if (audioDevice == null)
{
string[] audioDevices = new string[SDL.SDL_GetNumAudioDevices(0)];
for (int i = 0; i < audioDevices.Length; i++)
{
audioDevices[i] = SDL.SDL_GetAudioDeviceName(i, 0);
}
audioDevice = audioDevices.Length > 0 ? audioDevices[0] : null;
}
outputDevice = SDL.SDL_OpenAudioDevice(audioDevice, 0, ref desired, out audioSpec, 0);
if (outputDevice == 0)
{
throw new ApplicationException("Failed to open audio device " + audioDevice + ": " + SDL.SDL_GetError());
}
}
if (audioSpec.format == SDL.AUDIO_S32)
{
bytesPerSample = (uint)audioSpec.channels * 4;
}
else if (audioSpec.format == SDL.AUDIO_S16 || audioSpec.format == SDL.AUDIO_F32)
{
bytesPerSample = (uint)audioSpec.channels * 2;
}
else if (audioSpec.format == SDL.AUDIO_S8 || audioSpec.format == SDL.AUDIO_U8)
{
bytesPerSample = (uint)audioSpec.channels * 1;
}
if (audioSpec.size == 0)
{
audioSpec.size = audioSpec.samples * bytesPerSample;
}
emptyBuffer = new byte[audioSpec.size];
audioBuffer = new byte[audioSpec.size];
lastCallback = 0.0;
bufferTimer = Stopwatch.StartNew();
if (outputDevice != 0)
{
SDL.SDL_PauseAudioDevice(outputDevice, 0);
}
}
