public static byte[] GetDataStream(string mlvFileName, string content, int prefetchCount)
{
MLVCachedReader cache = GetReader(mlvFileName);
eFileType type = GetFileType(content);
lock (cache.cachedFiles)
{
if (cache.cachedFiles.ContainsKey(content))
{
PrefetchNext(mlvFileName, content, prefetchCount - 1);
cache.cachedFiles[content].lastUseTime = DateTime.Now;
return(cache.cachedFiles[content].bufferedData);
}
}
switch (type)
{
case eFileType.Txt:
string info = GetInfoFields(mlvFileName).Aggregate <string>(addString);
return(ASCIIEncoding.ASCII.GetBytes(info));
case eFileType.Wav:
return(GetWaveDataStream(mlvFileName));
case eFileType.MJpeg:
return(GetMJpegDataStream(mlvFileName));
}
int frame = GetFrameNumber(mlvFileName, content);
/* read video frame with/out debayering dependig on filetype */
switch (type)
{
case eFileType.Dng:
case eFileType.Fits:
cache.handler.DebayeringEnabled = false;
break;
case eFileType.Jpg:
cache.handler.DebayeringEnabled = true;
break;
}
byte[] data = null;
Bitmap currentFrame = null;
MLVTypes.mlv_vidf_hdr_t vidfHeader = new MLVTypes.mlv_vidf_hdr_t();
/* seek to the correct block */
int block = cache.reader.GetVideoFrameBlockNumber((uint)frame);
if (block < 0)
{
throw new FileNotFoundException("Requested video frame " + frame + " but thats not in the file index");
}
/* ensure that multiple threads dont conflict */
lock (cache)
{
/* read it */
cache.reader.CurrentBlockNumber = block;
cache.handler.VidfHeader.blockSize = 0;
cache.reader.ReadBlock();
/* now the VIDF should be read correctly */
if (cache.handler.VidfHeader.blockSize == 0)
{
throw new InvalidDataException("Requested video frame " + frame + " but the index points us wrong");
}
/* get all data we need */
switch (type)
{
case eFileType.Dng:
case eFileType.Fits:
data = cache.handler.RawPixelData;
vidfHeader = cache.handler.VidfHeader;
break;
case eFileType.Jpg:
if (cache.handler.CurrentFrame != null)
{
currentFrame = new Bitmap(cache.handler.CurrentFrame);
}
break;
}
}
/* process it */
switch (type)
{
case eFileType.Fits:
{
object[] metadata = cache.reader.GetVideoFrameMetadata((uint)frame);
byte[] stream = FITSCreator.Create(mlvFileName, vidfHeader, data, metadata);
PrefetchSave(mlvFileName, content, eFileType.Dng, frame, stream);
PrefetchNext(mlvFileName, content, prefetchCount);
return(stream);
}
case eFileType.Dng:
{
object[] metadata = cache.reader.GetVideoFrameMetadata((uint)frame);
byte[] stream = DNGCreator.Create(mlvFileName, vidfHeader, data, metadata);
PrefetchSave(mlvFileName, content, eFileType.Dng, frame, stream);
PrefetchNext(mlvFileName, content, prefetchCount);
return(stream);
}
case eFileType.Jpg:
{
JpegBitmapEncoder encoder = new JpegBitmapEncoder();
Stream stream = new MemoryStream();
encoder.QualityLevel = 90;
if (currentFrame != null)
{
encoder.Frames.Add(BitmapFrame.Create(BitmapSourceFromBitmap(currentFrame)));
encoder.Save(stream);
stream.Seek(0, SeekOrigin.Begin);
}
stream.Seek(0, SeekOrigin.Begin);
byte[] buffer = new byte[stream.Length];
stream.Read(buffer, 0, buffer.Length);
stream.Close();
PrefetchSave(mlvFileName, content, eFileType.Jpg, frame, buffer);
PrefetchNext(mlvFileName, content, prefetchCount);
return(buffer);
}
}
throw new FileNotFoundException("Requested frame " + frame + " of type " + type + " but we dont support that");
}