/// <summary>
/// Parses the GPS data from the specified <paramref name="bmpMetadata" /> and returns the data in an instance of <see cref="GpsLocation" />.
/// </summary>
/// <param name="bmpMetadata">An object containing the metadata.</param>
/// <returns>An instance of <see cref="GpsLocation" />.</returns>
public static GpsLocation Parse(IWpfMetadata bmpMetadata)
{
GpsLocation gps = new GpsLocation();
gps.Version = GetVersion(bmpMetadata);
gps.Latitude = GetLatitude(bmpMetadata);
gps.Longitude = GetLongitude(bmpMetadata);
gps.Altitude = GetAltitude(bmpMetadata);
gps.DestLatitude = GetDestLatitude(bmpMetadata);
gps.DestLongitude = GetDestLongitude(bmpMetadata);
//// Combine date portion of gpsDate or gpsDate2 with time portion of gpsTime2
//object gpsDate = bmpMetadata.GetQuery("System.GPS.Date"); // System.Runtime.InteropServices.ComTypes.FILETIME
//object gpsDate2 = bmpMetadata.GetQuery("/app1/ifd/gps/{ushort=29}"); // 2010:08:08
//DateTime gpsDate3 = Convert((System.Runtime.InteropServices.ComTypes.FILETIME)gpsDate);
//ulong[] gpsTime2 = bmpMetadata.GetQuery("/app1/ifd/gps/{ushort=7}") as ulong[]; // ulong[3]
//double hh = SplitLongAndDivide(gpsTime2[0]);
//double mm = SplitLongAndDivide(gpsTime2[1]);
//double ss = SplitLongAndDivide(gpsTime2[2]);
//object satellites = bmpMetadata.GetQuery("System.GPS.Satellites"); //"05"
//object satellites2 = bmpMetadata.GetQuery("/app1/ifd/gps/{ushort=8}"); //"05"
//double longitude = ConvertCoordinate(longitudeArray);
return(gps);
}
/// <summary>
/// Invokes the <see cref="BitmapMetadata.GetQuery" /> method on <paramref name="bmpMetadata" />, passing in the specified
/// <paramref name="query" />. Any <see cref="NotSupportedException" /> exceptions are silently swallowed.
/// </summary>
/// <param name="bmpMetadata">An object containing the metadata.</param>
/// <param name="query">The query to execute against <paramref name="bmpMetadata" />.</param>
/// <returns></returns>
private static object GetQuery(IWpfMetadata bmpMetadata, string query)
{
try
{
return(bmpMetadata.GetQuery(query));
}
catch (NotSupportedException) { return(null); }
catch (System.Runtime.InteropServices.COMException) { return(null); }
}
/// <summary>
/// Gets the destination longitude GPS data from <paramref name="bmpMetadata" />.
/// </summary>
/// <param name="bmpMetadata">An object containing the metadata.</param>
/// <returns>An instance of <see cref="GpsDistance" />.</returns>
private static GpsDistance GetDestLongitude(IWpfMetadata bmpMetadata)
{
string direction = GetQuery(bmpMetadata, "System.GPS.DestLongitudeRef") as string ?? GetQuery(bmpMetadata, @"/app1/ifd/gps/{ushort=21}") as string;
double[] longitude = GetQuery(bmpMetadata, "System.GPS.DestLongitude") as double[] ?? ConvertCoordinate(GetQuery(bmpMetadata, @"/app1/ifd/gps/{ushort=22}") as ulong[]);
if (!String.IsNullOrEmpty(direction) && (longitude != null))
{
return(new GpsDistance(direction, longitude[0], longitude[1], longitude[2]));
}
else
{
return(null);
}
}
/// <summary>
/// Determines whether the GPS altitude is above or below sea level. Returns <c>false</c> if the metadata is not present.
/// </summary>
/// <param name="bmpMetadata">An object containing the metadata.</param>
/// <returns>
/// <c>true</c> if the GPS position is below sea level; otherwise, <c>false</c>.
/// </returns>
private static bool IsBelowSeaLevel(IWpfMetadata bmpMetadata)
{
object directionObj = GetQuery(bmpMetadata, "System.GPS.AltitudeRef") ?? GetQuery(bmpMetadata, @"/app1/ifd/gps/{ushort=5}");
bool isBelowSeaLevel = false;
if (directionObj != null)
{
try
{
isBelowSeaLevel = (Convert.ToByte(directionObj, CultureInfo.InvariantCulture) == 1); // 0 = above sea level; 1 = below sea level
}
catch (InvalidCastException) { }
}
return(isBelowSeaLevel);
}
/// <summary>
/// Gets the version of the GPS information. Example: "2.2.0.0"
/// </summary>
/// <param name="bmpMetadata">An object containing the metadata.</param>
/// <returns>An instance of <see cref="System.String" />.</returns>
private static string GetVersion(IWpfMetadata bmpMetadata)
{
string version = String.Empty;
byte[] versionTokens = GetQuery(bmpMetadata, "System.GPS.VersionID") as byte[] ?? GetQuery(bmpMetadata, @"/app1/ifd/gps/{ushort=0}") as byte[];
if (versionTokens == null)
{
return(version);
}
foreach (byte versionToken in versionTokens)
{
version += versionToken + ".";
}
return(version.TrimEnd(new[] { '.' }));
}
private static double?GetAltitude(IWpfMetadata bmpMetadata)
{
object altObj = GetQuery(bmpMetadata, "System.GPS.Altitude");
if (altObj == null)
{
altObj = GetQuery(bmpMetadata, @"/app1/ifd/gps/{ushort=6}");
if (altObj != null)
{
altObj = ConvertCoordinate(new[] { (ulong)altObj })[0];
}
}
if (altObj == null)
{
return(null);
}
return(IsBelowSeaLevel(bmpMetadata) ? (double)altObj * (-1) : (double)altObj);
}
/// <summary>
/// Determines whether the GPS altitude is above or below sea level. Returns <c>false</c> if the metadata is not present.
/// </summary>
/// <param name="bmpMetadata">An object containing the metadata.</param>
/// <returns>
/// <c>true</c> if the GPS position is below sea level; otherwise, <c>false</c>.
/// </returns>
private static bool IsBelowSeaLevel(IWpfMetadata bmpMetadata)
{
object directionObj = GetQuery(bmpMetadata, "System.GPS.AltitudeRef") ?? GetQuery(bmpMetadata, @"/app1/ifd/gps/{ushort=5}");
bool isBelowSeaLevel = false;
if (directionObj != null)
{
try
{
isBelowSeaLevel = (Convert.ToByte(directionObj, CultureInfo.InvariantCulture) == 1); // 0 = above sea level; 1 = below sea level
}
catch (InvalidCastException) { }
}
return isBelowSeaLevel;
}
/// <summary>
/// Gets the version of the GPS information. Example: "2.2.0.0"
/// </summary>
/// <param name="bmpMetadata">An object containing the metadata.</param>
/// <returns>An instance of <see cref="System.String" />.</returns>
private static string GetVersion(IWpfMetadata bmpMetadata)
{
string version = String.Empty;
byte[] versionTokens = GetQuery(bmpMetadata, "System.GPS.VersionID") as byte[] ?? GetQuery(bmpMetadata, @"/app1/ifd/gps/{ushort=0}") as byte[];
if (versionTokens == null) return version;
foreach (byte versionToken in versionTokens)
{
version += versionToken + ".";
}
return version.TrimEnd(new[] { '.' });
}
/// <summary>
/// Invokes the <see cref="BitmapMetadata.GetQuery" /> method on <paramref name="bmpMetadata" />, passing in the specified
/// <paramref name="query" />. Any <see cref="NotSupportedException" /> exceptions are silently swallowed.
/// </summary>
/// <param name="bmpMetadata">An object containing the metadata.</param>
/// <param name="query">The query to execute against <paramref name="bmpMetadata" />.</param>
/// <returns></returns>
private static object GetQuery(IWpfMetadata bmpMetadata, string query)
{
try
{
return bmpMetadata.GetQuery(query);
}
catch (NotSupportedException) { return null; }
catch (System.Runtime.InteropServices.COMException) { return null; }
}
/// <summary>
/// Gets the longitude GPS data from <paramref name="bmpMetadata" />.
/// </summary>
/// <param name="bmpMetadata">An object containing the metadata.</param>
/// <returns>An instance of <see cref="GpsDistance" />.</returns>
private static GpsDistance GetLongitude(IWpfMetadata bmpMetadata)
{
string direction = GetQuery(bmpMetadata, "System.GPS.LongitudeRef") as string ?? GetQuery(bmpMetadata, @"/app1/ifd/gps/{ushort=3}") as string;
double[] longitude = GetQuery(bmpMetadata, "System.GPS.Longitude") as double[] ?? ConvertCoordinate(GetQuery(bmpMetadata, @"/app1/ifd/gps/{ushort=4}") as ulong[]);
if (!String.IsNullOrEmpty(direction) && (longitude != null))
{
return new GpsDistance(direction, longitude[0], longitude[1], longitude[2]);
}
else
{
return null;
}
}
private static double? GetAltitude(IWpfMetadata bmpMetadata)
{
object altObj = GetQuery(bmpMetadata, "System.GPS.Altitude");
if (altObj == null)
{
altObj = GetQuery(bmpMetadata, @"/app1/ifd/gps/{ushort=6}");
if (altObj != null)
{
altObj = ConvertCoordinate(new[] { (ulong)altObj })[0];
}
}
if (altObj == null)
{
return null;
}
return (IsBelowSeaLevel(bmpMetadata) ? (double)altObj * (-1) : (double)altObj);
}
/// <summary>
/// Parses the GPS data from the specified <paramref name="bmpMetadata" /> and returns the data in an instance of <see cref="GpsLocation" />.
/// </summary>
/// <param name="bmpMetadata">An object containing the metadata.</param>
/// <returns>An instance of <see cref="GpsLocation" />.</returns>
public static GpsLocation Parse(IWpfMetadata bmpMetadata)
{
GpsLocation gps = new GpsLocation();
gps.Version = GetVersion(bmpMetadata);
gps.Latitude = GetLatitude(bmpMetadata);
gps.Longitude = GetLongitude(bmpMetadata);
gps.Altitude = GetAltitude(bmpMetadata);
gps.DestLatitude = GetDestLatitude(bmpMetadata);
gps.DestLongitude = GetDestLongitude(bmpMetadata);
//// Combine date portion of gpsDate or gpsDate2 with time portion of gpsTime2
//object gpsDate = bmpMetadata.GetQuery("System.GPS.Date"); // System.Runtime.InteropServices.ComTypes.FILETIME
//object gpsDate2 = bmpMetadata.GetQuery("/app1/ifd/gps/{ushort=29}"); // 2010:08:08
//DateTime gpsDate3 = Convert((System.Runtime.InteropServices.ComTypes.FILETIME)gpsDate);
//ulong[] gpsTime2 = bmpMetadata.GetQuery("/app1/ifd/gps/{ushort=7}") as ulong[]; // ulong[3]
//double hh = SplitLongAndDivide(gpsTime2[0]);
//double mm = SplitLongAndDivide(gpsTime2[1]);
//double ss = SplitLongAndDivide(gpsTime2[2]);
//object satellites = bmpMetadata.GetQuery("System.GPS.Satellites"); //"05"
//object satellites2 = bmpMetadata.GetQuery("/app1/ifd/gps/{ushort=8}"); //"05"
//double longitude = ConvertCoordinate(longitudeArray);
return gps;
}
