/// <summary>
/// GenerateNext is called by the Generator base class when the next sample should be read.
/// </summary>
/// <param name="previous">Time of previous sample.</param>
/// <returns>Time for current sample.</returns>
protected override DateTime GenerateNext(DateTime previous)
{
DateTime originatingTime = default(DateTime);
int streamIndex = 0;
SourceReaderFlags flags = SourceReaderFlags.None;
long timestamp = 0;
Sample sample = this.sourceReader.ReadSample(SourceReaderIndex.AnyStream, 0, out streamIndex, out flags, out timestamp);
if (sample != null)
{
originatingTime = this.start + TimeSpan.FromTicks(timestamp);
MediaBuffer buffer = sample.ConvertToContiguousBuffer();
int currentByteCount = 0;
int maxByteCount = 0;
IntPtr data = buffer.Lock(out maxByteCount, out currentByteCount);
if (streamIndex == this.imageStreamIndex)
{
using (var sharedImage = ImagePool.GetOrCreate(this.videoWidth, this.videoHeight, Imaging.PixelFormat.BGR_24bpp))
{
sharedImage.Resource.CopyFrom(data);
this.Image.Post(sharedImage, originatingTime);
}
}
else if (streamIndex == this.audioStreamIndex)
{
AudioBuffer audioBuffer = new AudioBuffer(currentByteCount, this.waveFormat);
Marshal.Copy(data, audioBuffer.Data, 0, currentByteCount);
this.Audio.Post(audioBuffer, originatingTime);
}
buffer.Unlock();
buffer.Dispose();
sample.Dispose();
}
if (flags == SourceReaderFlags.Endofstream)
{
return(DateTime.MaxValue); // Used to indicated there is no more data
}
if (originatingTime <= previous)
{
return(previous + TimeSpan.FromTicks(1)); // To enforce strictly increasing times for the generator
}
return(originatingTime);
}
public BufferHelper(Sample sample, int sampleHeight)
{
buffer2D = null;
buffer = sample.ConvertToContiguousBuffer();
buffer2D = buffer.QueryInterfaceOrNull <SharpDX.MediaFoundation.Buffer2D>();
int length = 0, pitch = 0;
if (buffer2D != null)
{
byte[] arr = new byte[IntPtr.Size];
buffer2D.Lock2D(arr, out pitch);
length = buffer2D.ContiguousLength;
Data = new IntPtr(BitConverter.ToInt32(arr, 0));
}
else
{
int curlen;
Data = buffer.Lock(out length, out curlen);
pitch = length / sampleHeight;
}
Length = length;
Pitch = pitch;
}
/// <summary>
/// Gets the decoded PCM samples. See remarks.
/// </summary>
/// <param name="startingPositionInSeconds">The starting position in seconds.</param>
/// <returns>An enumerator of pointer to PCM decoded data with the same format as returned by <see cref="WaveFormat"/>.</returns>
/// <remarks>
/// This method is only working as a single enumerator at a time.
/// The <see cref="SetSourceStream(System.IO.Stream)"/> must be set before calling <see cref="GetSamples()"/>
/// </remarks>
public IEnumerable<DataPointer> GetSamples(TimeSpan startingPositionInSeconds)
{
// A new reader is setup, so initialize it.
lock (sourceReaderLock)
{
// If the reader was changed
if (nextSourceReader != null)
{
if (sourceReader != null)
sourceReader.Dispose();
sourceReader = nextSourceReader;
nextSourceReader = null;
}
}
// Make sure that any prior call
CleanupAndDispose();
CheckIfDisposed();
// Set the position
sourceReader.SetCurrentPosition((long)(startingPositionInSeconds.TotalSeconds * 1e7));
while (true)
{
int streamIndex;
SourceReaderFlags flags;
long time;
CheckIfDisposed();
using (currentSample = sourceReader.ReadSample(SourceReaderIndex.FirstAudioStream, SourceReaderControlFlags.None, out streamIndex, out flags, out time))
{
if ((flags & SourceReaderFlags.Endofstream) != 0)
break;
CheckIfDisposed();
using (currentBuffer = currentSample.ConvertToContiguousBuffer())
{
int bufferMaxLength;
int bufferCurrentLength;
CheckIfDisposed();
var ptr = currentBuffer.Lock(out bufferMaxLength, out bufferCurrentLength);
yield return new DataPointer(ptr, bufferCurrentLength);
// Warning, because the yield could never return here, currentBuffer and currentSample should be disposed when disposing this object or when
// calling it again on the GetSamples method.
// In case a Dispose occured while decoding
if (currentBuffer == null)
break;
currentBuffer.Unlock();
}
}
}
// They have been disposed, so we can just clear them
currentBuffer = null;
currentSample = null;
}
/// <summary>
/// GenerateNext is called by the Generator base class when the next sample should be read.
/// </summary>
/// <param name="currentTime">The originating time that triggered the current call.</param>
/// <returns>The originating time at which to capture the next sample.</returns>
protected override DateTime GenerateNext(DateTime currentTime)
{
DateTime originatingTime = default(DateTime);
int streamIndex = 0;
SourceReaderFlags flags = SourceReaderFlags.None;
long timestamp = 0;
Sample sample = this.sourceReader.ReadSample(SourceReaderIndex.AnyStream, 0, out streamIndex, out flags, out timestamp);
if (sample != null)
{
originatingTime = this.start + TimeSpan.FromTicks(timestamp);
MediaBuffer buffer = sample.ConvertToContiguousBuffer();
int currentByteCount = 0;
int maxByteCount = 0;
IntPtr data = buffer.Lock(out maxByteCount, out currentByteCount);
if (streamIndex == this.imageStreamIndex)
{
// Detect out of order originating times
if (originatingTime > this.lastPostedImageTime)
{
using (var sharedImage = ImagePool.GetOrCreate(this.videoWidth, this.videoHeight, Imaging.PixelFormat.BGR_24bpp))
{
sharedImage.Resource.CopyFrom(data);
this.Image.Post(sharedImage, originatingTime);
this.lastPostedImageTime = originatingTime;
}
}
else if (!this.dropOutOfOrderPackets)
{
throw new InvalidOperationException(
$"The most recently captured image frame has a timestamp ({originatingTime.TimeOfDay}) which is before " +
$"that of the last posted image frame ({this.lastPostedImageTime.TimeOfDay}), as reported by the video stream. This could " +
$"be due to a timing glitch in the video stream. Set the 'dropOutOfOrderPackets' " +
$"parameter to true to handle this condition by dropping " +
$"packets with out of order timestamps.");
}
}
else if (streamIndex == this.audioStreamIndex)
{
// Detect out of order originating times
if (originatingTime > this.lastPostedAudioTime)
{
AudioBuffer audioBuffer = new AudioBuffer(currentByteCount, this.waveFormat);
Marshal.Copy(data, audioBuffer.Data, 0, currentByteCount);
this.Audio.Post(audioBuffer, originatingTime);
this.lastPostedAudioTime = originatingTime;
}
else if (!this.dropOutOfOrderPackets)
{
throw new InvalidOperationException(
$"The most recently captured audio buffer has a timestamp ({originatingTime.TimeOfDay}) which is before " +
$"that of the last posted audio buffer ({this.lastPostedAudioTime.TimeOfDay}), as reported by the audio stream. This could " +
$"be due to a timing glitch in the audio stream. Set the 'dropOutOfOrderPackets' " +
$"parameter to true to handle this condition by dropping " +
$"packets with out of order timestamps.");
}
}
buffer.Unlock();
buffer.Dispose();
sample.Dispose();
}
if (flags == SourceReaderFlags.Endofstream)
{
return(DateTime.MaxValue); // Used to indicated there is no more data
}
return(originatingTime);
}
