* {{Parameter|existingImageHandle&}} is a valid handle to a graphic QB64 image in memory, created with [[_NEWIMAGE]], [[_LOADIMAGE]] or [[_COPYIMAGE]].
* You can pass [[_SOURCE]], [[_DEST]] or [[_DISPLAY]] to copy the current source, destination or active display pages, as long as they are valid graphic images.
* SCREEN 0 handles (created either with [[_NEWIMAGE]] or passed using _DEST while in a text screen) are not valid and will create an [[ERROR Codes|Illegal Function Call]] or [[ERROR Codes|Invalid Handle]] error.
* [[Keywords_currently_not_supported_by_QB64#Keywords_Not_Supported_in_Linux_or_MAC_OSX_versions|Not available in Linux or macOS]].