public static VelodyneNmeaPacket Parse(String nmeaStr)
{
try
{
String[] tsnmeas = nmeaStr.Split(','); // hhmmss.ss
if (tsnmeas.Length > 0)
{
String dateStr = default(DateTime).ToString("yyyy-MM-dd ") + tsnmeas[1].Substring(0, 2) + ":" + tsnmeas[1].Substring(2, 2) + ":" + tsnmeas[1].Substring(4, 2);
DateTime time_nmea = DateTime.ParseExact(dateStr, "yyyy-MM-dd HH:mm:ss", System.Globalization.CultureInfo.InvariantCulture);
VelodyneNmeaPacket packet = new VelodyneNmeaPacket(time_nmea);
packet.LatDeg = Convert.ToInt32(tsnmeas[3].Substring(0, 2));
packet.LatMin = Convert.ToDouble(tsnmeas[3].Substring(2, 6));
packet.LonDeg = Convert.ToInt32(tsnmeas[5].Substring(0, 3));
packet.LonMin = Convert.ToDouble(tsnmeas[5].Substring(3, 6));
packet.NmeaString = nmeaStr;
return(packet);
}
else
{
//throw new Exception("NMEA seems empty: " + nmeaStr);
return(null);
}
}
catch (Exception)
{
//throw new Exception("Couldn't parse NMEA data! NMEA message: " + nmeaStr + " Excaption: " + ex.Message);
return(null);
}
}
public IndexData(DateTime packetTimeStamp, DateTime internalTimeStamp, long position, String nmea)
{
this.PacketTimeStamp = packetTimeStamp;
this.Nmea = VelodyneNmeaPacket.Parse(nmea);
this.InternalTimeStamp = internalTimeStamp;
this.Position = position;
}
public static VelodyneNmeaPacket ReadRecordNMEA(byte[] packet)
{
int i = 42 + 198;
double ts = BitConverter.ToUInt32(new byte[] { packet[i], packet[i + 1], packet[i + 2], packet[i + 3] }, 0) / 1000000.00;
i = i + 8;
byte[] nmeaMessageArray = new byte[75];
for (int j = 0; j < 75; j++)
{
nmeaMessageArray[j] = packet[i + j];
}
String nmeaStr = System.Text.Encoding.ASCII.GetString(nmeaMessageArray);
VelodyneNmeaPacket nmeaPacket = VelodyneNmeaPacket.Parse(nmeaStr);
return(nmeaPacket);
}
public void Convert(CancellationToken cancellationToken = default(CancellationToken))
{
FileInfo fi = new FileInfo(PcapFile);
long fileSize = fi.Length;
BinaryWriter idxWriter = new BinaryWriter(File.Open(GetDefaultIndexFile(PcapFile), FileMode.Create));
OfflinePacketDevice selectedDevice = new OfflinePacketDevice(PcapFile);
PacketCommunicator communicator =
selectedDevice.Open(65536, // portion of the packet to capture
// 65536 guarantees that the whole packet will be captured on all the link layers
PacketDeviceOpenAttributes.Promiscuous, // promiscuous mode
1000); // read timeout
using (BinaryWriter pointWriter = new BinaryWriter(File.Open(GetDefaultPointFile(PcapFile), FileMode.Create)))
{
Packet packet;
bool isEof = false;
VelodyneNmeaPacket lastNmea = null;
long sumBytes = 0;
long indexId = 0;
while (!isEof)
{
if (cancellationToken.IsCancellationRequested)
{
idxWriter.Close();
cancellationToken.ThrowIfCancellationRequested();
}
PacketCommunicatorReceiveResult result = communicator.ReceivePacket(out packet);
switch (result)
{
case PacketCommunicatorReceiveResult.Timeout:
case PacketCommunicatorReceiveResult.Ok:
sumBytes += packet.Length;
if (packet.Length == 554)
{
lastNmea = PacketInterpreter.ReadRecordNMEA(packet.Buffer);
indexId++;
}
else
{
pointWriter.Write(packet.Timestamp.Ticks);
pointWriter.Write(packet.Buffer);
if (lastNmea != null)
{
int l = packet.Length - 6; // this is the end of the pack!
double internal_time = BitConverter.ToUInt32(new byte[] { packet[l], packet[l + 1], packet[l + 2], packet[l + 3] }, 0) / 1000000.00;
DateTime utcPacketTimestamp = packet.Timestamp.ToUniversalTime();
DateTime time = (new DateTime(utcPacketTimestamp.Year, utcPacketTimestamp.Month, utcPacketTimestamp.Day, utcPacketTimestamp.Hour, 0, 0)).AddSeconds(internal_time);
idxWriter.Write(time.Ticks);
idxWriter.Write(packet.Timestamp.Ticks);
idxWriter.Write(pointWriter.BaseStream.Position);
byte[] nmea_byte = Encoding.ASCII.GetBytes(lastNmea.NmeaString.PadRight(NMEA_LENGTH, ' '));
idxWriter.Write(nmea_byte);
if (indexId % 100 == 0)
{
ProgressReportEventArgs args = new ProgressReportEventArgs((((double)sumBytes / (double)fileSize) * 100.0), sumBytes, utcPacketTimestamp);
OnReportProgress(args);
}
lastNmea = null;
}
}
break;
case PacketCommunicatorReceiveResult.Eof:
isEof = true;
break;
default:
throw new InvalidOperationException("The result " + result + " should never be reached here");
}
}
}
idxWriter.Close();
}
