HP L 5 manual Raster Scaling, Resolution Scaling, Arbitrary Scaling

Raster Scaling

Raster scaling provides the ability to enlarge or reduce raster images using the Destination Raster Width and Destination Raster Height commands. The Start Raster command (?*r#A) with a value field of 2 or 3 turns on scale mode. Scaling is independent of device resolution.

Note	To use raster scaling, the Configure Image Data command (?*r#W)
	must be sent prior to the Start Raster command (?*r#A), which must
	have a value field of 2 or 3 to enable scaling.
	There are two types of raster scaling: Resolution and Arbitrary. The
	scaling type is selected by the argument to the Start Raster
	command. If either 0 or 1 are used then resolution scaling is
	performed. If either 2 or 3 is used then arbitrary scaling is performed.
	Resolution Scaling
	This scaling is performed using the raster resolution in combination
	with the device resolution. For example, if the raster resolution is set
	to 300 dpi and the device resolution is 600 dpi, then the image is
	scaled by a factor of two. This type of scaling does not depend on the
	source or destination raster dimensions.
	Arbitrary Scaling
	This scaling is performed without regard to the raster resolution which
	is unaffected by scale calculations. The scaling factor is determined
	by the source and destination raster dimensions. If the destination
	dimensions are not specified the graphics margin and printable area
	are used to calculated destination dimensions while maintaining
	isotropic scaling so that the entire image fits on the page. If only one
	destination boundary is specified the other is calculated to maintain
	isotropic scaling.
	The destination width and height commands accept real numbers
	with up to four decimal places of precision. This level of precision is
	necessary when converting from decipoints to pixels so that round off
	errors will not create visible print artifacts such as lines within the
	image.

6-36 Raster Graphics EN