public static byte[] ConvertData(Type dataType, ExifType targetType, object value)
{
switch (targetType)
{
case ExifType.Ascii:
{
return(Encoding.ASCII.GetBytes(Convert.ToString(value) + '\0'));
}
case ExifType.Byte:
case ExifType.Raw:
{
if (dataType == typeof(UnicodeEncoding))
{
return(Encoding.Unicode.GetBytes(Convert.ToString(value) + '\0'));
}
return(ExifEncoder.WriteBytes(value));
}
case ExifType.Int32:
{
return(ExifEncoder.WriteInt32(value));
}
case ExifType.Rational:
{
return(ExifEncoder.WriteRational(value));
}
case ExifType.UInt16:
{
return(ExifEncoder.WriteUInt16(value));
}
case ExifType.UInt32:
{
return(ExifEncoder.WriteUInt32(value));
}
case ExifType.URational:
{
return(ExifEncoder.WriteURational(value));
}
default:
{
throw new NotImplementedException(String.Format("Encoding for EXIF type \"{0}\" has not yet been implemented.", targetType));
}
}
}
/// <summary>
/// Adds an EXIF property to an image.
/// </summary>
/// <param name="image"></param>
/// <param name="property"></param>
public static void AddExifData(Image image, ExifProperty property)
{
if (image == null)
{
throw new ArgumentNullException("image");
}
if (property == null)
{
return;
}
PropertyItem propertyItem;
// The .NET interface for GDI+ does not allow instantiation of the
// PropertyItem class. Therefore one must be stolen off the Image
// and repurposed. GDI+ uses PropertyItem by value so there is no
// side effect when changing the values and reassigning to the image.
if (image.PropertyItems == null || image.PropertyItems.Length < 1)
{
propertyItem = ExifWriter.CreatePropertyItem();
}
else
{
propertyItem = image.PropertyItems[0];
}
propertyItem.Id = (int)property.Tag;
propertyItem.Type = (short)property.Type;
Type dataType = ExifDataTypeAttribute.GetDataType(property.Tag);
propertyItem.Value = ExifEncoder.ConvertData(dataType, property.Type, property.Value);
propertyItem.Len = propertyItem.Value.Length;
// This appears to not be necessary
ExifWriter.RemoveExifData(image, property.Tag);
image.SetPropertyItem(propertyItem);
}
