/// <summary>
/// Initializes a new <see cref="OpusEncoder"/> instance, with the specified codec usage tuning, sample rate and channels.
/// </summary>
/// <param name="optimized">The codec usage tuning.</param>
/// <param name="sampleRate">The sample rate in the input audio.</param>
/// <param name="audioChannels">The channels in the input audio - mono or stereo.</param>
public OpusEncoder(OpusOptimizer optimized, OpusSampleRate sampleRate, OpusAudioChannels audioChannels)
{
if (!Enum.IsDefined(typeof(OpusOptimizer), optimized))
{
throw new ArgumentException("Value is not defined in the enumeration.", nameof(optimized));
}
if (!Enum.IsDefined(typeof(OpusSampleRate), sampleRate))
{
throw new ArgumentException("Value is not defined in the enumeration.", nameof(sampleRate));
}
if (!Enum.IsDefined(typeof(OpusAudioCHannels), audioChannels))
{
throw new ArgumentException("Value is not defined in the enumeration.", nameof(audioChannels));
}
_handle = FFI.opus_encoder_create((int)sampleRate, (int)audioChannels, (int)optimized, out int error);
ThrowIfError(error);
Optimized = optimized;
SampleRate = sampleRate;
AudioChannels = audioChannels;
Bitrate = -1;
}
private OpusDecoder(double frameSize, OpusSampleRate sampleRate, OpusAudioChannels audioChannels, bool frameSizeWasSpecified)
{
switch (frameSize)
{
case 2.5:
case 5:
case 10:
case 20:
case 40:
case 60:
break;
default:
throw new ArgumentException("Value must be one of the following: 2.5, 5, 10, 20, 40 or 60.", nameof(frameSize));
}
if (!Enum.IsDefined(typeof(OpusSampleRate), sampleRate))
{
throw new ArgumentException("Value is not defined in the enumeration.", nameof(sampleRate));
}
if (!Enum.IsDefined(typeof(OpusAudioCHannels), audioChannels))
{
throw new ArgumentException("Value is not defined in the enumeration.", nameof(audioChannels));
}
if (frameSizeWasSpecified)
{
FrameSize = frameSize;
}
SampleRate = sampleRate;
AudioChannels = audioChannels;
_samples = GetSampleCount(frameSize);
_pcmLength = GetPCMLength(_samples);
_handle = FFI.opus_decoder_create((int)sampleRate, (int)audioChannels, out int error);
ThrowIfError(error);
}
protected override bool ReleaseHandle()
{
FFI.opus_encoder_destroy(handle);
return(true);
}
/// <summary>
/// Encodes an Opus frame, the frame size must be one of the following: 2.5, 5, 10, 20, 40 or 60 ms.
/// </summary>
/// <param name="pcmBytes">The Opus frame.</param>
/// <param name="pcmLength">The maximum number of bytes to read from <paramref name="pcmBytes"/>.</param>
/// <param name="opusBytes">The buffer that the encoded audio will be stored in.</param>
/// <param name="opusLength">The maximum number of bytes to write to <paramref name="opusBytes"/>.
/// This will determine the bitrate in the encoded audio.</param>
/// <returns>The number of bytes written to <paramref name="opusBytes"/>.</returns>
public unsafe int Encode(byte[] pcmBytes, int pcmLength, byte[] opusBytes, int opusLength)
{
if (pcmBytes == null)
{
throw new ArgumentNullException(nameof(pcmBytes));
}
if (pcmLength < 0)
{
throw new ArgumentOutOfRangeException(nameof(pcmLength), "Value cannot be negative.");
}
if (pcmBytes.Length < pcmLength)
{
throw new ArgumentOutOfRangeException(nameof(pcmLength), $"Value cannot be greater than the length of {nameof(pcmBytes)}.");
}
if (opusBytes == null)
{
throw new ArgumentNullException(nameof(opusBytes));
}
if (opusLength < 0)
{
throw new ArgumentOutOfRangeException(nameof(opusLength), "Value cannot be negative.");
}
if (opusBytes.Length < opusLength)
{
throw new ArgumentOutOfRangeException(nameof(opusLength), $"Value cannot be greater than the length of {nameof(opusBytes)}.");
}
double frameSize = GetFrameSize(pcmLength);
switch (frameSize)
{
case 2.5:
case 5:
case 10:
case 20:
case 40:
case 60:
break;
default:
throw new ArgumentException("The frame size must be one of the following: 2.5, 5, 10, 20, 40 or 60.", nameof(pcmLength));
}
ThrowIfDisposed();
int result;
int samples = GetSampleCount(frameSize);
fixed(byte *input = pcmBytes)
fixed(byte *output = opusBytes)
{
var inputPtr = (IntPtr)input;
var outputPtr = (IntPtr)output;
result = FFI.opus_encode(_handle, inputPtr, samples, outputPtr, opusLength);
}
ThrowIfError(result);
return(result);
}