User Guide

CHAPTER 12. DIALOGS 94
Finding Contiguous Regions
Default Threshold Here you can choose the default threshold for all tools which is a
measure for the precision of filling and masking tools.
12.7 Environment Settings
12.7.1 Resource Consumption
Conservative Memory Usage
The GIMP is optimized to speed i.e. speed is more important than memory usage.
Enabling “Conservative Memory Usage” will “optimize” GIMP to use less memory. The
tradeoff is of course speed but if your system is low on memory then it can be an option
to use “Conservative Memory Usage”.
Levels of Undo
By default GIMP has five levels of undo. The amount of undo levels is only limited by
disk space. A high amount of undo levels requires a large amount of disk space so use
it with care. The default value is reasonably good for most use.
Tile Cache Size
This is the most important parameter that GIMP has. If you set it too low, GIMP will be
very slow. There isn’t a upper level of how much memory that you can give GIMP. That
is to say, give GIMP as much as you can. But don’t give GIMP more that your physical
memory (i.e. pure memory without swap). In reality you have to measure how much
memory you usually use and give GIMP a little less than the rest of it.
12.7.2 Scaling
Interpolation Type
When you scale an image (make it bigger), you have to fill in missing pixels. The color
and value that those pixels should have is calculated in a interpolation algorithm. GIMP
uses a Linear interpolation algorithm by default. Linear gives you a mid-quality interpo-
lation. Linear interpolation has less quality trade off for speed than Nearest Neighbour
interpolation algorithm does. Nearest Neighbour is the fastest way to interpolate, but
it has the lowest quality of the interpolation algorithms. The Cubic interpolation algo-
rithm produces the highest quality of the three interpolation types supported by GIMP.
However it is considerably slower than the linear interpolation algorithm.
12.7.3 File Saving
Try to Write a Thumbnail File
By default when you save an image, a thumbnail file will be created – storing a little
image of your image. When you mark an image in the file open dialog, you will see this