/// <summary>
/// Decodes audio data.
/// </summary>
/// <returns>Returns a decoded IAudioData buffer or null if no more buffer available.</returns>
public IAudioData Decode()
{
if (m_Disposed)
{
throw new ObjectDisposedException(LogSourceName);
}
BufferFrame();
// end of file ? -> yes exit
if (m_DecodeFifoBuffer.Length == 0)
{
return(null);
}
var outBuffer = new FifoBuffer();
bool l_Loop = true;
while (l_Loop)
{
M123.RESULT result;
result = M123.SafeNativeMethods.mpg123_decode(m_DecoderHandle, m_DecodeFifoBuffer, outBuffer, 8192);
switch (result)
{
case M123.RESULT.NEED_MORE:
if (outBuffer.Length > 0)
{
l_Loop = false;
break;
}
BufferFrame();
if (m_DecodeFifoBuffer.Length == 0)
{
return(null);
}
break;
case M123.RESULT.NEW_FORMAT: UpdateFormat(); break;
default: M123.CheckResult(result); throw new InvalidOperationException();
}
}
if (outBuffer.Length > 0)
{
var resultData = new AudioData(m_CurrentConfig.SamplingRate, m_CurrentConfig.Format, m_CurrentConfig.ChannelSetup, m_CurrentTimeStamp, 0, -1, outBuffer.ToArray());
m_CurrentTimeStamp += resultData.Duration;
return(resultData);
}
return(null);
}
/// <summary>Closes the underlying stream and calls Dispose.</summary>
public void Close()
{
if (m_Disposed)
{
throw new ObjectDisposedException(LogSourceName);
}
if (m_Initialized)
{
M123.Deinitialize();
m_Initialized = false;
}
if (m_Source != null)
{
m_Source.Close();
m_Source = null;
m_DecodeFifoBuffer = null;
}
}
/// <summary>Starts the decoding process.</summary>
/// <param name="source">The source.</param>
/// <exception cref="InvalidOperationException">Source: Decoding already started!.</exception>
public void BeginDecode(IFrameSource source)
{
if (disposed)
{
throw new ObjectDisposedException(LogSourceName);
}
if (initialized)
{
throw new InvalidOperationException(string.Format("Source {0}: Decoding already started!", SourceName));
}
if (SourceName != null)
{
SourceName = source.Name;
}
initialized = true;
M123.Initialize();
m_Source = source;
// open new decoder handle
M123.RESULT result;
m_DecoderHandle = M123.SafeNativeMethods.mpg123_new(null, out result);
M123.CheckResult(result);
// reset formats
M123.CheckResult(M123.SafeNativeMethods.mpg123_format_none(m_DecoderHandle));
// allow all mp3 native samplerates
var mode = useFloatingPoint ? M123.ENC.FLOAT_32 : M123.ENC.SIGNED_16;
foreach (var sampleRate in M123.SafeNativeMethods.mpg123_rates())
{
M123.CheckResult(M123.SafeNativeMethods.mpg123_format(m_DecoderHandle, new IntPtr(sampleRate), M123.CHANNELCOUNT.STEREO, mode));
}
// open feed
result = M123.SafeNativeMethods.mpg123_open_feed(m_DecoderHandle);
M123.CheckResult(result);
m_DecodeFifoBuffer = new FifoBuffer();
}
