static T[] readArray <T>(Mp4Reader reader) where T : unmanaged
{
sHeader header = reader.readStructure <sHeader>();
int count = header.entry_count.endian();
return(readArray <T>(reader, count));
}
public static ChunkOffsetTable readOffsets32(Mp4Reader reader)
{
Debug.Assert(reader.currentBox == eBoxType.stco);
sHeader header = reader.readStructure <sHeader>();
int count = header.entry_count.endian();
uint[] entries = readArray <uint>(reader, count);
return(new ChunkOffsetTable32(entries));
}
internal static CompositionTimeDeltas read(Mp4Reader reader)
{
Debug.Assert(reader.currentBox == eBoxType.ctts);
sHeader header = reader.readStructure <sHeader>();
int count = header.entry_count.endian();
if (count <= 0)
{
return(null);
}
bool signedIntegers;
switch (header.version)
{
case 0:
signedIntegers = false;
break;
case 1:
signedIntegers = true;
break;
default:
// Warning because videos actually play OK even when ignoring the data from that box.
Logger.logWarning("ctts box has unexpected version {0}", header.version);
return(null);
}
// That thing takes couple MB of RAM. Bypassing the GC with malloc/free.
IntPtr nativePointer = Marshal.AllocHGlobal(count * 8);
try
{
Span <CttsEntryUnsigned> span = Unsafe.writeSpan <CttsEntryUnsigned>(nativePointer, count);
reader.read(span.asBytes());
if (signedIntegers)
{
var signed = MemoryMarshal.Cast <CttsEntryUnsigned, CttsEntrySigned>(span);
return(parseSigned(signed));
}
return(parseUnsigned(span));
}
finally
{
Marshal.FreeHGlobal(nativePointer);
}
}
public static ChunkOffsetTable readOffsets64(Mp4Reader reader)
{
Debug.Assert(reader.currentBox == eBoxType.co64);
sHeader header = reader.readStructure <sHeader>();
int count = header.entry_count.endian();
long[] entries = new long[count];
reader.read(entries.AsSpan().asBytes());
for (int i = 0; i < entries.Length; i++)
{
entries[i] = entries[i].endian();
}
return(new ChunkOffsetTable64(entries));
}
public ZipFile(Stream strm,bool read)
{
_strm = strm;
if (read)
_bw = new BinaryWriter(new GZipStream(_strm, CompressionMode.Compress, true));
else
{
_br = new BinaryReader(new GZipStream(_strm, CompressionMode.Decompress, true));
_files = new Dictionary<string, byte[]>();
while (_br.BaseStream.Position < _br.BaseStream.Length)
{
sHeader head = new sHeader(_br.ReadBytes(512));
_files.Add(head.Name, _br.ReadBytes((int)head.Size));
}
}
}
