private static IEnumerable <byte[]> MicrosoftPlayReadyObjectHeader(byte[] data)
{
// PlayReady Header specs:
// https://docs.microsoft.com/en-us/playready/specifications/playready-header-specification
ushort playReadyObjectRecordCount = LittleEndian.AsUShort16(data, 4);
var offset = 6;
for (var i = 0; i < playReadyObjectRecordCount; i++)
{
ushort recordType = LittleEndian.AsUShort16(data, offset);
ushort recordLength = LittleEndian.AsUShort16(data, offset + 2);
// Reserved/Unspecified record type... ignoring
if (recordType == 0 || recordType > 3)
{
offset += recordLength;
continue;
}
var playReadyHeader = Encoding.Unicode.GetString(data, offset + 4, recordLength);
var xDoc = XDocument.Parse(playReadyHeader);
if (xDoc.Root == null)
{
continue;
}
var kids = xDoc.Descendants(xDoc.Root.Name.Namespace + "KID");
foreach (XElement kid in kids)
{
Logger.Info(kid.Value);
// PlayReady KeyIds are in LE format. (each uuid block)
// Pssh box KeyIds are in BE format
//
// Use BE as common format - more human friendly - byte
// ordering as in cannonical mpd form
//
// UUID Note:
// Last 8 bytes of UUID are provided "as is" (i.e. BE form)
yield return
(LittleEndian.AsCanonicalUuid(Convert.FromBase64String(kid.Value), 0, DashUuidFormat));
}
}
}
