-(void)sayWhat
{
   NSString *doIOwnThisIWonder = [NSString stringWithFormat:@"%@",@"Nope"];
   NSImage *iOwnThisImage = [[NSImage alloc] initWithContentsOfFile:@"/tmp/youownthis.jpg"];
   NSData *perhapsThisData=[iOwnThisImage TIFFRepresentation]; 

   ... do my thing ...

  [iOwnThisImage release];
}