TagLib.Ogg.PageHeader.PageHeader C# (CSharp) Method

        public PageHeader(File file, long position)
        {
            if (file == null)
                throw new ArgumentNullException ("file");

            if (position < 0 || position > file.Length - 27)
                throw new ArgumentOutOfRangeException (
                    "position");

            file.Seek (position);

            // An Ogg page header is at least 27 bytes, so we'll go
            // ahead and read that much and then get the rest when
            // we're ready for it.

            ByteVector data = file.ReadBlock (27);
            if (data.Count < 27 || !data.StartsWith ("OggS"))
                System.Console.WriteLine(
                    "Error reading page header");

            version = data [4];
            this.flags = (PageFlags) data [5];
            absolute_granular_position = data.Mid(6, 8).ToULong (
                false);
            stream_serial_number = data.Mid(14, 4).ToUInt (false);
            page_sequence_number = data.Mid(18, 4).ToUInt (false);

            // Byte number 27 is the number of page segments, which
            // is the only variable length portion of the page
            // header. After reading the number of page segments
            // we'll then read in the coresponding data for this
            // count.
            int page_segment_count = data [26];
            ByteVector page_segments =
                file.ReadBlock (page_segment_count);

            // Another sanity check.
            if (page_segment_count < 1 ||
                page_segments.Count != page_segment_count)
                System.Console.WriteLine(
                    "Incorrect number of page segments");

            // The base size of an Ogg page 27 bytes plus the number
            // of lacing values.
            size = (uint)(27 + page_segment_count);
            packet_sizes = new List<int> ();

            int packet_size = 0;
            data_size = 0;

            for (int i = 0; i < page_segment_count; i++) {
                data_size += page_segments [i];
                packet_size += page_segments [i];

                if (page_segments [i] < 255) {
                    packet_sizes.Add (packet_size);
                    packet_size = 0;
                }
            }

            if (packet_size > 0)
                packet_sizes.Add (packet_size);
        }