private void ParseForMp3Frames(Stream stream, bool enableSeeking)
{
Mp3Frame frame = null;
long offsetOfFirstFrame = 0;
stream = new BufferedStream(stream);
if (enableSeeking)
{
while (ID3v2.SkipTag(stream))
{
/* skip all id3 tags (see https://github.com/filoe/cscore/issues/63)
* there are some files with multiple id3v2 tags
* not sure whether this is according to the id3 specification but we have to handle it anyway
* as long as the SkipTag method returns true, another id3 tag has been found
*/
}
}
while (frame == null)
{
if (enableSeeking && stream.IsEndOfStream())
{
break;
}
if (enableSeeking)
{
offsetOfFirstFrame = stream.Position;
}
frame = Mp3Frame.FromStream(stream);
}
if (frame == null)
{
throw new Exception("Could not find any MP3-Frames in the stream.");
}
if (enableSeeking)
{
XingHeader xingHeader = XingHeader.FromFrame(frame);
if (xingHeader != null)
{
offsetOfFirstFrame = stream.Position;
}
}
_inputFormat = new Mp3Format(frame.SampleRate, frame.ChannelCount, frame.FrameLength, frame.BitRate);
//Prescan stream
if (enableSeeking)
{
_frameInfoCollection = new FrameInfoCollection();
while (_frameInfoCollection.AddFromMp3Stream(stream))
{
}
stream.Position = offsetOfFirstFrame;
}
}
/// <summary>
/// Disposes the <see cref="DmoMp3Decoder"/>.
/// </summary>
/// <param name="disposing">True to release both managed and unmanaged resources; false to release only unmanaged resources.</param>
protected override void Dispose(bool disposing)
{
base.Dispose(disposing);
if (_comObj != null)
{
Marshal.ReleaseComObject(_comObj);
_comObj = null;
}
if (_frameInfoCollection != null)
{
_frameInfoCollection.Dispose();
_frameInfoCollection = null;
}
if (_stream != null && _closeStream)
{
_stream.Dispose();
_stream = null;
}
}