private void Decode(Stream stream, FlacMetadataStreamInfo streamInfo)
{
Header = new FlacFrameHeader(stream, streamInfo);
_stream = stream;
_streamInfo = streamInfo;
HasError = Header.HasError;
if (!HasError)
{
ReadSubFrames();
FreeBuffers();
}
}
public static void ProcessResidual(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data,
int order, int partitionOrder, FlacResidualCodingMethod codingMethod)
{
data.Content.UpdateSize(partitionOrder);
var isRice2 = codingMethod == FlacResidualCodingMethod.PartitionedRice2;
var riceParameterLength = isRice2 ? 5 : 4;
var escapeCode = isRice2 ? 31 : 15; //11111 : 1111
var partitionCount = 1 << partitionOrder; //2^partitionOrder -> There will be 2^order partitions. -> "order" = partitionOrder in this case
var residualBuffer = data.ResidualBuffer.Span.Slice(order);
for (var p = 0; p < partitionCount; p++)
{
int samplesPerPartition;
if (partitionOrder == 0)
{
samplesPerPartition = header.BlockSize - order;
}
else if (p > 0)
{
samplesPerPartition = header.BlockSize >> partitionOrder;
}
else
{
samplesPerPartition = (header.BlockSize >> partitionOrder) - order;
}
var riceParameter = reader.ReadBits(riceParameterLength);
data.Content.Parameters[p] = (int)riceParameter;
if (riceParameter >= escapeCode)
{
var raw = reader.ReadBits(5); //raw is always 5 bits (see ...(+5))
data.Content.RawBits[p] = (int)raw;
for (var i = 0; i < samplesPerPartition; i++)
{
var sample = reader.ReadBitsSigned((int)raw);
residualBuffer[i] = sample;
}
}
else
{
ReadFlacRiceBlock(reader, samplesPerPartition, (int)riceParameter, residualBuffer);
}
residualBuffer = residualBuffer.Slice(samplesPerPartition);
}
}
private unsafe List <FlacFrameInformation> ScanThisShit(FlacMetadataStreamInfo streamInfo)
{
var stream = _stream;
//if (!(stream is BufferedStream))
// stream = new BufferedStream(stream);
var buffer = new byte[BufferSize];
stream.Position = 4; //fLaC
//skip the metadata
FlacMetadata.SkipMetadata(stream);
var frames = new List <FlacFrameInformation>();
var frameInfo = new FlacFrameInformation {
IsFirstFrame = true
};
FlacFrameHeader baseHeader = null;
while (true)
{
var read = stream.Read(buffer, 0, buffer.Length);
if (read <= FlacConstant.FrameHeaderSize)
break;
fixed(byte *bufferPtr = buffer)
{
var ptr = bufferPtr;
//for (int i = 0; i < read - FlacConstant.FrameHeaderSize; i++)
while ((bufferPtr + read - FlacConstant.FrameHeaderSize) > ptr)
{
if (*ptr++ == 0xFF && (*ptr & 0xF8) == 0xF8) //check sync
{
var ptrSafe = ptr;
ptr--;
if (IsFrame(ref ptr, streamInfo, out var tmp))
{
var header = tmp;
if (frameInfo.IsFirstFrame)
{
baseHeader = header;
frameInfo.IsFirstFrame = false;
}
if (baseHeader != null && baseHeader.IsFormatEqualTo(header))
{
frameInfo.StreamOffset = stream.Position - read + ((ptrSafe - 1) - bufferPtr);
frameInfo.Header = header;
frames.Add(frameInfo);
frameInfo.SampleOffset += header.BlockSize;
}
else
{
ptr = ptrSafe;
}
}
else
{
ptr = ptrSafe;
}
}
}
}
stream.Position -= FlacConstant.FrameHeaderSize;
}
