private long TrimResult()
{
if (_lastHeader == null)
{
return(0L);
}
// Trim zero byte stuffing from last header (if any)
string zeroByteStuffingName = Enum.GetName(typeof(NalUnitParser.Attribute), NalUnitParser.Attribute.TrailingZeroBytes);
var zeroByteStuffingAttribute = _lastHeader.FindAttributeByName(zeroByteStuffingName);
if (zeroByteStuffingAttribute == null)
{
return(0L);
}
uint byteCount = (uint)zeroByteStuffingAttribute.Value;
// Rebuild the last header, omitting the zero byte stuffing attribute
var resultNodeBuilder = new ResultNodeBuilder
{
Name = _lastHeader.Name,
Metadata = _lastHeader,
DataPacket = _lastHeader.GetSubPacket(0, (_lastHeader.Length - byteCount))
};
foreach (IResultAttribute attribute in _lastHeader.Attributes.Where(a => a.Name != zeroByteStuffingName))
{
resultNodeBuilder.AddAttribute(attribute);
}
// Replace the last header with the new (trimmed) header
IResultNode parent = _lastHeader.Parent;
parent.RemoveChild(_lastHeader);
parent.AddChild(resultNodeBuilder.Build());
// Compensate end offset for zero byte trimming
return(-byteCount);
}
public IDataBlock DetectData(IDataReader dataReader, IDataBlockBuilder dataBlockBuilder, IScanContext context)
{
long startOffset = dataReader.Position;
long endOffset = dataReader.Length;
IMetadata metadata = new Metadata(CodecID.Unknown, context.Detectors);
IResultNode root = new RootResult(metadata, dataReader.GetDataPacket(0, 1).InputFile);
IResultNodeBuilder resultNodeBuilder = new ResultNodeBuilder
{
Name = "Data",
Metadata = metadata,
DataPacket = dataReader.GetDataPacket(startOffset, (endOffset - startOffset))
};
root.AddChild(resultNodeBuilder.Build());
context.Results = root;
dataBlockBuilder.DataFormat = CodecID.Unknown;
dataBlockBuilder.StartOffset = startOffset;
dataBlockBuilder.EndOffset = endOffset;
dataReader.Position = endOffset;
return(dataBlockBuilder.Build());
}