private byte[] DownloadFileInBlocks(string fileName)
{
CloudBlobContainer cloudBlobContainer = GetContainerReference();
CloudBlockBlob blob = cloudBlobContainer.GetBlockBlobReference(Path.GetFileName(fileName));
int blockSize = 1024 * 1024; // 1 MB block size
blob.FetchAttributes();
long fileSize = blob.Properties.Length;
byte[] blobContents = new byte[fileSize];
int position = 0;
while (fileSize > 0)
{
int blockLength = (int)Math.Min(blockSize, fileSize);
blob.DownloadRangeToByteArray(blobContents, position, position, blockLength);
position += blockLength;
fileSize -= blockSize;
}
return(blobContents);
}
public List <VideoMediaBuffer> GetVideoMediaBuffers(long currentTick)
{
Stopwatch watch = new Stopwatch();
watch.Start();
// 1. Downlaod _nbSecondToLoad seconds of video content from the storage account
long bufferSize = _frameSize * _videoFormat.FrameRate * _nbSecondToLoad;
byte[] bytesToRead = new byte[bufferSize];
var nbByteRead = _videoBlob.DownloadRangeToByteArray(bytesToRead, 0, _videoOffset, bytesToRead.Length, null, null);
//2. Extract each video frame in a VideoMediaBuffer object
List <VideoMediaBuffer> videoMediaBuffers = new List <VideoMediaBuffer>();
long referenceTime = currentTick;
for (int index = 0; index < nbByteRead; index += _frameSize)
{
IntPtr unmanagedBuffer = Marshal.AllocHGlobal(_frameSize);
Marshal.Copy(bytesToRead, index, unmanagedBuffer, _frameSize);
referenceTime += _frameDurationInTicks;
var videoSendBuffer = new VideoSendBuffer(unmanagedBuffer, (uint)_frameSize, _videoFormat, referenceTime);
videoMediaBuffers.Add(videoSendBuffer);
_videoOffset += _frameSize;
}
Log.Info(new CallerInfo(), LogContext.FrontEnd, $"Loading {_nbSecondToLoad}s video took {watch.ElapsedMilliseconds}ms ({_frameSize * _videoFormat.FrameRate * _nbSecondToLoad} bytes)");
watch.Stop();
return(videoMediaBuffers);
}
public static GenericBufferedStream ToStream(this CloudBlockBlob blob)
{
Func <long, byte[], int> filler = (remoteOffset, buffer) =>
{
var read = blob.DownloadRangeToByteArray(buffer, 0, remoteOffset, buffer.Length);
return(read);
};
return(new GenericBufferedStream(blob.Properties.Length, filler));
}
public List <Code> GenerateCodesFromCloudFile(long[] offset)
{
var cFile = new CloudBlockBlob(CloudFile);
var codes = new List <Code>();
for (var i = offset[0]; i < offset[1]; i += 4)
{
var bytes = new byte[4];
cFile.DownloadRangeToByteArray(bytes, index: 0, blobOffset: i, length: 4);
var seedValue = BitConverter.ToInt32(bytes, 0);
var code = new Code()
{
SeedValue = seedValue
};
codes.Add(code);
}
return(codes);
}
public List <AudioMediaBuffer> GetAudioMediaBuffers(long currentTick)
{
Stopwatch watch = new Stopwatch();
watch.Start();
// 1. Downlaod _nbSecondToLoad seconds of audio content from the storage account
long bufferSize = 16000 * 2 * _nbSecondToLoad; // Pcm16K is 16000 samples per seconds, each sample is 2 bytes
byte[] bytesToRead = new byte[bufferSize];
var nbByteRead = _audioBlob.DownloadRangeToByteArray(bytesToRead, 0, _audioOffset, bytesToRead.Length, null, null);
//2. Extract each audio sample in a AudioMediaBuffer object
List <AudioMediaBuffer> audioMediaBuffers = new List <AudioMediaBuffer>();
int audioBufferSize = (int)(16000 * 2 * 0.02); // the Real-time media platform expects audio buffer duration of 20ms
long referenceTime = currentTick;
for (int index = 0; index < nbByteRead; index += audioBufferSize)
{
IntPtr unmanagedBuffer = Marshal.AllocHGlobal(audioBufferSize);
Marshal.Copy(bytesToRead, index, unmanagedBuffer, audioBufferSize);
// 10000 ticks in a ms
referenceTime += 20 * 10000;
var audioBuffer = new AudioSendBuffer(unmanagedBuffer, audioBufferSize, _audioFormat, referenceTime);
audioMediaBuffers.Add(audioBuffer);
_audioOffset += audioBufferSize;
}
Log.Info(new CallerInfo(), LogContext.FrontEnd, $"Loading {_nbSecondToLoad}s audio took {watch.ElapsedMilliseconds}ms ({16000 * 2 * _nbSecondToLoad} bytes)");
watch.Stop();
return(audioMediaBuffers);
}