EN Introduction 15-3
The final data reduction technique provided by the raster area 
involves the printer’s ability to fill in trailing zeros to the edge of the 
raster area. Any zeros following the last “1“ in the raster row to the 
edge of the picture area need not be sent. The printer automatically 
fills them. This technique eliminates the need to transmit raster data 
rows that are all the same length, as required in a raster image which 
does not use the raster area feature.
The raster area represents a boundary. Within this boundary the 
printer zero-fills missing rows and fills in short rows to the edge of 
the raster area. However, in addition to filling to the boundaries of 
the raster area, the printer also clips any raster line which extends 
beyond the boundary. Thus, if an image extends beyond the raster 
area, then that portion of the image is not printed.
When the raster area reduction techniques are used in conjunction 
with the raster compression techniques, a considerable savings in 
data can be realized. This results in a saving of host storage and 
data transmission time. However, these reduction techniques do not 
reduce the amount of printer memory required for page formatting.