arts-pdf crackerjack 5.1 User Manual

 

 

 

should resample images when they are at a higher resolution than the intended 
output device supports. Note that images never resample to a higher resolution, only 

to a lower one.  
 

When subsampling an image, a pixel is selected in a sample to represent that area at 
the new resolution. You provide the resolution, and the Image feature selects pixels 

as needed to reduce the image’s resolution to the specified dpi setting. 
 

Downsampling uses a weighted average of pixels in a sample area to determine pixel 
color and usually yields better results than subsampling. The Image feature provides 
several filters for downsampling. Each filter produces differing results and, depending 

on the image, one filter may produce a better appearance than another. Lantana has 
tested a range of sample color images at different source and destination resolutions 

and found that “Lanczos 3” produces consistently good results. 

 

 
This tool allows the user to crop the currently selected image.  
 

 

 

Figure 20. Crop Panel 

 
The window will initially display the original image size, in pixels, in the field named 

“New Image Size:”. As values are entered in the Left, Right, Top, or Bottom boxes 
two things will be apparent in the window. First, dashed lines will appear to indicate 

the part of the image which will remain (inside the lines) and which will be discarded 
(outside the lines). As values are entered the New Image Size values will also be 

updated to show what the image size will be after cropping. 

 
If an attempt is made to crop an image which has a mask or clipping path, the user 

will be presented with a dialog which offers a choice of removing the mask, keeping 
it, or canceling the operation. Note that applying cropping without removing the 

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