Northern Eclipse Help Reference

 Resample


This function is used to generate an image that has different dimensions from the source image.

This function works on the current image.  Unlike the Zoom command, this function calculates the intermediate pixels according to the sampling method and generates an image with the new dimensions.  This can be used to scale down an image that is too big to fit on the screen.  We do not recommend scaling an image before performing any densitometric measurements since the intensities are generally changed during the resampling process.  By Locking the XY, you can change an image size without changing it’s aspect ratio.

Sampling Method

An image only has data at its integer locations.  This function generates non-integer pixel locations.  Eclipse can compensate for this by using a sampling method to determine the data at the non-integer locations.  

Bi-Cubic – This method looks at the 16 pixels surrounding the non-integer point of interest and forms a continuous bi-cubic surface.  It then samples this surface at the non-integer point and uses this as a value (see Bi-Cubic).  This method does the most processing and generally looks the best, but it also deviates the most from the original image data.

Bi-Linear – This method looks at the 4 pixels surrounding the non-integer point of interest and forms a continuous bi-linear plane.  It then samples this plane at the non-integer point and uses this as a value  (see Bi-Linear).  This method is a compromise between Bi-Cubic and truncation.  It still generates data not found in the original image but not to the extent as Bi-Cubic and it is also faster.

Truncation – This method discards the non-integer portion of the point and treats it as an integer point.  This method has the advantage of using data values that exist in the image, and it is the fastest.  Its disadvantage is that it has the worst visual appearance.


See Also

Morph, Flip Horizontal, Flip Vertical

References

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