Autodesk 551A1-05B111-1001 - Stitcher Unlimited 2009, Руководство пользователя

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Chapter 3
User Guide
166
scale an image, Stitcher estimates the pixel values in the final image by interpolating the
values from the original image.
You can set the interpolation type in the Preferences dialog:
The different algorithms that Stitcher uses are described as follows:
Nearest : The value of the new pixel is the same as that of the closest existing pixel.
When enlarging an image, these techniques duplicate pixels. When reducing the size
of an image, they delete pixels. This is the fastest method.
Bilinear : This method uses the values from the four surrounding pixels, that is,
above, below, right, and left of the spot where the new pixel is to be created. The new
pixel value is determined by calculating a weighted average of the four closest pixels
(a 2 × 2 array) based on distance.
This method tends to make an image softer, that is, the contrast is reduced because of
averaging neighboring values together.
Bicubic and Michell : As with bilinear sampling, these methods determine the values
of new pixels by calculating the weighted average of the closest 16 pixels (4 × 4 array)
based on distance. As with bilinear resampling, these methods tend to make an image
softer. So it is a good idea to apply some sharpening to the image to reduce the
softness.