public static bool AddModifyTag(Image img, EXIFTag tag, string value)
{
//using the tag type, decode how to parse string -> bytes
switch (tag)
{
case EXIFTag.GPSLatitude:
case EXIFTag.GPSLongitude:
return(AddModifyLongLat(img, value, tag));
case EXIFTag.GPSAltitude:
return(AddModifyRational(img, value, tag));
case EXIFTag.GPSAltitudeReference:
return(AddModifyAltitudeRef(img, value, tag));
case EXIFTag.UserComment:
case EXIFTag.DateTime:
case EXIFTag.DateTimeOriginal:
return(AddModifyTag(img, tag, Encoding.ASCII.GetBytes(value.ToCharArray()), EXIFTypes.ASCII));
default:
return(false);
}
return(false); // unhandled type encountered
}
public static string EXIFTagToString(EXIFTag tag)
{
switch (tag)
{
case EXIFTag.Ignored: return("Ignored");
case EXIFTag.FileName: return("File Name");
case EXIFTag.UserComment: return("User Comment");
case EXIFTag.DateTime: return("Date & Time");
case EXIFTag.DateTimeOriginal: return("Date & Time Original");
// case EXIFTag.DateTimeDigitized: return "Date & Time Digitized";
case EXIFTag.GPSLatitude: return("GPS Latitude");
case EXIFTag.GPSLongitude: return("GPS Longitude");
case EXIFTag.GPSAltitude: return("GPS Altitude (m)");
case EXIFTag.GPSAltitudeReference: return("GPS Altitude Ref");
}
return(""); // fallthrough
}
private static bool AddModifyRational(Image img, string value, EXIFTag tag)
{
//strip useless chars
value = new string(value.Where(c => char.IsDigit(c) || c == '.').ToArray());
float sourceVal = float.Parse(value, System.Globalization.NumberStyles.Float);
var results = ConvertFloatToRational(sourceVal);
return(AddModifyTag(img, tag, results, EXIFTypes.rational));
}
private static bool AddModifyTag(Image img, EXIFTag tag, byte[] value, EXIFTypes type)
{
// Read - modify - write
if ((int)tag > 0)
{
var existingTag = img.GetPropertyItem((int)tag);
existingTag.Id = (int)tag;
existingTag.Type = (short)type;
existingTag.Value = value;
existingTag.Len = value.Length;
img.SetPropertyItem(existingTag);
}
return(true);
}
private static bool AddModifyAltitudeRef(Image img, string value, EXIFTag tag)
{
value = value.ToLower();
byte parsedValue = 0;
if (value.Contains("above") || value.Contains("0"))
{
parsedValue = 0;
}
else if (value.Contains("below") || value.Contains("1"))
{
parsedValue = 1;
}
else
{
return(false);
}
return(AddModifyTag(img, tag, new byte[] { parsedValue }, EXIFTypes.Byte));
}
private static EXIFTypes TagToType(EXIFTag tag)
{
switch (tag)
{
case EXIFTag.Ignored: return(EXIFTypes.Undefined);
case EXIFTag.FileName: return(EXIFTypes.ASCII);
case EXIFTag.UserComment: return(EXIFTypes.ASCII);
case EXIFTag.DateTime: return(EXIFTypes.ASCII);
case EXIFTag.DateTimeOriginal: return(EXIFTypes.ASCII);
// case EXIFTag.DateTimeDigitized: return "Date & Time Digitized";
case EXIFTag.GPSLatitude: return(EXIFTypes.rational);
case EXIFTag.GPSLongitude: return(EXIFTypes.rational);
case EXIFTag.GPSAltitude: return(EXIFTypes.rational);
}
return(EXIFTypes.Undefined); // fallthrough
}
private static bool AddModifyLongLat(Image img, string value, EXIFTag tag)
{
//parse the provided dd.mmmm or dd.mmm.sss format into a float
float deg = 0, min = 0, sec = 0;
if (value.Contains("'"))
{
//DMS
var value2 = value.Replace("'", "").Replace("°", "").Replace("\"", "").Replace("-", "");
var split = value2.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
if (split.Length == 3 || split.Length == 4)
{
//We are good
deg = float.Parse(split[0], System.Globalization.NumberStyles.Float);
min = float.Parse(split[1], System.Globalization.NumberStyles.Float);
sec = float.Parse(split[2], System.Globalization.NumberStyles.Float);
}
}
else
{
//Deg decimal
// TODO NEEDS Testing
var value2 = value.Replace("'", "").Replace("°", "").Replace("\"", "").Replace("-", "");
float source = float.Parse(value2);
deg = (int)(source);
source -= deg;
source *= 60;
min = (int)source;
source -= min;
source *= 60;
sec = source;
}
string directionSign = "";
if (value.Contains("S") || value.Contains("-") || value.Contains("W"))
{
if (tag == EXIFTag.GPSLatitude)
{
directionSign = "S";
}
else if (tag == EXIFTag.GPSLongitude)
{
directionSign = "W";
}
}
else
{
if (tag == EXIFTag.GPSLatitude)
{
directionSign = "N";
}
else if (tag == EXIFTag.GPSLongitude)
{
directionSign = "W";
}
}
if (tag == EXIFTag.GPSLatitude)
{
//GPSLatitudeRef = 0x001,
if (AddModifyTag(img, (EXIFTag)0x0001, Encoding.ASCII.GetBytes(directionSign), EXIFTypes.ASCII) == false)
{
return(false);
}
}
else if (tag == EXIFTag.GPSLongitude)
{
//GPSLongitudeRef = 0x0003,
if (AddModifyTag(img, (EXIFTag)0x0003, Encoding.ASCII.GetBytes(directionSign), EXIFTypes.ASCII) == false)
{
return(false);
}
}
//Convert this float into the byte[] array desired for 3 rationals
var results = ConvertFloatToRational(deg).Concat(ConvertFloatToRational(min).Concat(ConvertFloatToRational(sec))).ToArray();
return(AddModifyTag(img, tag, results, EXIFTypes.rational));
}
