/// <summary>
/// Parse the metadata of a data block.
/// </summary>
public Block(Stream reader, MatroskaTree source)
{
source.Position(reader);
this.reader = reader;
long start = reader.Position;
Track = VarInt.ReadValue(reader);
TimeStamp = reader.ReadInt16BE();
flags = (byte)reader.ReadByte();
Lacing lacing = LacingType;
if (lacing != Lacing.None)
{
int x = reader.ReadByte();
frameCount = x + 1;
frameSizes = new int[frameCount];
firstFrame = reader.Position;
switch (lacing)
{
case Lacing.Xiph:
byte frame = 0;
long totalSize = 0;
while (frame < frameCount - 1)
{
byte value;
int sum = 0;
do
{
value = (byte)reader.ReadByte();
sum += value;
} while (value == 255);
totalSize += sum;
frameSizes[frame++] = sum;
}
frameSizes[frame] = (int)(source.Length - (reader.Position - start) - totalSize);
break;
case Lacing.FixedSize:
int step = (int)((source.Length - (firstFrame - start)) / frameCount);
for (byte i = 0; i < frameCount; ++i)
{
frameSizes[i] = step;
}
break;
case Lacing.EBML:
frameSizes[0] = (int)VarInt.ReadValue(reader);
long last = -frameSizes[0];
for (int i = 1; i < frameCount - 1; ++i)
{
frameSizes[i] = frameSizes[i - 1] + (int)VarInt.ReadSignedValue(reader);
last -= frameSizes[i];
}
frameSizes[frameCount - 1] = (int)(last + source.Length - (reader.Position - start));
break;
default:
break;
}
}
else
{
firstFrame = reader.Position;
frameCount = 1;
frameSizes = new int[1] {
(int)(source.Length - (firstFrame - start))
};
}
}
