def set_type gtype, name, value
      gvalue = GObject::GValue.alloc
      gvalue.init gtype
      gvalue.set value
      Vips::vips_image_set self, name, gvalue
    end
def set_type gtype, name, value
      gvalue = GObject::GValue.alloc
      gvalue.init gtype
      gvalue.set value
      Vips::vips_image_set self, name, gvalue
    end
Create a metadata item on an image of the specifed type. Ruby types
 are automatically transformed into the matching `GType`, if possible.

 For example, you can use this to set an image's ICC profile:

 ```
 x = y.set_type Vips::BLOB_TYPE, "icc-profile-data", profile
 ```

 where `profile` is an ICC profile held as a binary string object.

 @see set
 @param gtype [Integer] GType of item
 @param name [String] Metadata field to set
 @param value [Object] Value to set