(v13) ResamplingFactor (page device)
This page applies to Harlequin v13.1r0 and later; both Harlequin Core and Harlequin MultiRIP
Param | Val | ExType | Vers | Use? | HPS | Ref |
x | H | Y | All |
The value of the ResamplingFactor
page device key must be a positive integer. The default and minimum value is 1
.
When the RIP is producing screened output ResamplingFactor
must
be exactly 1
. When the RIP is producing a contone raster, and ResamplingFactor
is greater than 1
, the raster will be down-sampled (anti-aliased) during rendering. A ResamplingFactor
of 2
will mean that each final pixel is the average of a 2 x 2 cell of original pixels, a value of 3
will mean that each final pixel is the average of a 3 x 3 cell of original pixels, and so on. This results in smoother and more visually pleasing edges especially when the output is at low resolution—this is often referred to as anti-aliasing.
Because the down-sampling reduces the final resolution it is normal to increase the pre-down-sampled pixel count by multiplying the value of Scaling
in the page device by an equivalent amount, for example.
<<
/ResamplingFactor 2
/Scaling [ currentpagedevice /Scaling get aload pop exch 2 mul exch 2 mul ]
>> setpagedevice
Note:
This example is taken from the TIFF plugin code, and the implicit assumption that ResamplingFactor
is 1
before this code is called is therefore safe. Any code that may be called after a job has started, or even after other plugin code or page features, should account for the possibility that ResamplingFactor
has already been set to a different value. ResamplingFactor
is used by the TIFF plugin to implement the anti-alias control.
Large values will probably lead to vmerrors, and values greater than 4
are unlikely to produce significant quality improvement in most cases.
Note:
The TrimPage
page device key cannot be used with the ResamplingFactor
page device key. Default: 1