public ByteVector Render() { ByteVector vector = new ByteVector(); // add the file identifier -- "3DI" vector.Add(FileIdentifier); // add the version number -- we always render a 2.4.0 tag regardless of what // the tag originally was. vector.Add((byte)4); vector.Add((byte)0); // render and add the flags byte flags = 0; if (Desynchronization) { flags |= 128; } if (ExtendedHeader) { flags |= 64; } if (ExperimentalIndicator) { flags |= 32; } flags |= 16; vector.Add(flags); // add the size vector.Add(Id3v2SynchData.FromUInt(TagSize)); return(vector); }
protected void Parse(ByteVector data) { if (data != null) { size = Id3v2SynchData.ToUInt(data.Mid(0, 4)); } else { throw new ArgumentNullException("data"); } }
protected void Parse(ByteVector data) { if (data.Count < Size) { return; } // do some sanity checking -- even in ID3v2.3.0 and less the tag size is a // synch-safe integer, so all buffer must be less than 128. If this is not // true then this is an invalid tag. // note that we're doing things a little out of order here -- the size is // later in the bytestream than the version ByteVector sizeData = data.Mid(6, 4); if (sizeData.Count != 4) { tagSize = 0; TagLibDebugger.Debug("ID3v2.Header.Parse () - The tag size as read was 0 bytes!"); return; } foreach (byte b in sizeData) { if (b >= 128) { tagSize = 0; TagLibDebugger.Debug("ID3v2.Header.Parse () - One of the size bytes in the id3v2 header was greater than the allowed 128."); return; } } // The first three buffer, data[0..2], are the File Identifier, "ID3". (structure 3.1 "file identifier") // Read the version number from the fourth and fifth buffer. majorVersion = data[3]; // (structure 3.1 "major version") revisionNumber = data[4]; // (structure 3.1 "revision number") // Read the flags, the first four bits of the sixth byte. byte flags = data[5]; desynchronization = ((flags >> 7) & 1) == 1; // (structure 3.1.a) extendedHeader = ((flags >> 6) & 1) == 1; // (structure 3.1.b) experimentalIndicator = ((flags >> 5) & 1) == 1; // (structure 3.1.channelMode) footerPresent = ((flags >> 4) & 1) == 1; // (structure 3.1.d) // Get the size from the remaining four buffer (read above) tagSize = Id3v2SynchData.ToUInt(sizeData); // (structure 3.1 "size") }
public ByteVector Render() { ByteVector flags = new ByteVector(2, (byte)0); // just blank for the moment return(frameId + Id3v2SynchData.FromUInt(frameSize) + flags); }
public void SetData(ByteVector data, uint version) { if (data != null) { this.version = version; if (version < 3) { // ID3v2.2 if (data.Count < 3) { TagLibDebugger.Debug("You must at least specify a frame ID."); return; } // Set the frame ID -- the first three buffer frameId = data.Mid(0, 3); // If the full header information was not passed in, do not continue to the // steps to parse the frame size and flags. if (data.Count < 6) { frameSize = 0; return; } frameSize = data.Mid(3, 3).ToUInt(); } else if (version == 3) { // ID3v2.3 if (data.Count < 4) { TagLibDebugger.Debug("You must at least specify a frame ID."); return; } // Set the frame ID -- the first four buffer frameId = data.Mid(0, 4); // If the full header information was not passed in, do not continue to the // steps to parse the frame size and flags. if (data.Count < 10) { frameSize = 0; return; } // Set the size -- the frame size is the four buffer starting at byte four in // the frame header (structure 4) frameSize = data.Mid(4, 4).ToUInt(); // read the first byte of flags tagAlterPreservation = ((data[8] >> 7) & 1) == 1; // (structure 3.3.1.a) fileAlterPreservation = ((data[8] >> 6) & 1) == 1; // (structure 3.3.1.b) readOnly = ((data[8] >> 5) & 1) == 1; // (structure 3.3.1.channelMode) // read the second byte of flags compression = ((data[9] >> 7) & 1) == 1; // (structure 3.3.1.index) encryption = ((data[9] >> 6) & 1) == 1; // (structure 3.3.1.j) groupingIdentity = ((data[9] >> 5) & 1) == 1; // (structure 3.3.1.k) } else { // ID3v2.4 if (data.Count < 4) { TagLibDebugger.Debug("You must at least specify a frame ID."); return; } // Set the frame ID -- the first four buffer frameId = data.Mid(0, 4); // If the full header information was not passed in, do not continue to the // steps to parse the frame size and flags. if (data.Count < 10) { frameSize = 0; return; } // Set the size -- the frame size is the four buffer starting at byte four in // the frame header (structure 4) frameSize = Id3v2SynchData.ToUInt(data.Mid(4, 4)); // read the first byte of flags tagAlterPreservation = ((data[8] >> 6) & 1) == 1; // (structure 4.1.1.a) fileAlterPreservation = ((data[8] >> 5) & 1) == 1; // (structure 4.1.1.b) readOnly = ((data[8] >> 4) & 1) == 1; // (structure 4.1.1.channelMode) // read the second byte of flags groupingIdentity = ((data[9] >> 6) & 1) == 1; // (structure 4.1.2.header) compression = ((data[9] >> 3) & 1) == 1; // (structure 4.1.2.k) encryption = ((data[9] >> 2) & 1) == 1; // (structure 4.1.2.m) desynchronization = ((data[9] >> 1) & 1) == 1; // (structure 4.1.2.n) dataLengthIndicator = (data[9] & 1) == 1; // (structure 4.1.2.position) } } else { throw new ArgumentNullException("data"); } }