If you have an image with relatively coarse resolution, for example with an image matrix of 128 × 128 pixels, then you may find it useful give the image a smoother appearance by turning interpolation on. Interpolation displays the image with four times as many pixels as are really in the image matrix, using bi-linear interpolation to the estimate the pixel intensity for the increased number of pixels. Because there are four times as many pixels displayed, each pixel is only a quarter of the original area, and thus image appears smoother.
You can turn interpolation on and off using by selecting the
Interpolated check-box in the View menu:
You may also find interpolation useful when you have zoomed in on a part of your image with a high zoom factor.
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|---|---|
| Un-Interpolated | Interpolated |
The images above show that interpolation smooths out some of the "blockyness" of images with few pixels, or highly-zoomed images. However, this can be at the expense of making the images appear more blurred.
Note: interpolation only affects the way the image appears on your computer screen. It does not affect the underlying pixel intensity values, image statistics etc.
Note: because Jim has to handle four times as many pixels, turning on interpolation slows down image display, scrolling etc.
Note: if you export a movie with interpolation turned on for the movie, the resulting animated GIF will contain four times as many pixels as it would without interpolation.