Page 214 - DCAP504_Computer Graphics

Unit 13: Advanced Computer Graphics

The following figure 13.18 depicts reverse mapping where each pixel in the destination image is
mapped by sampling appropriately in the source image.

Figure 13.18: Reverse Mapping

Source: http://www.cs.virginia.edu/~gfx/courses/2004/Intro.Fall.04/handouts/03-morph.pdf
The following figure 13.19 depicts how the pixels in the source image appear when re-sampled using
reverse mapping.

Figure 13.19: Reverse Mapping

Source: http://www.cs.virginia.edu/~gfx/courses/2004/Intro.Fall.04/handouts/03-morph.pdf
The reverse mapping method is a tedious process to identify the way in which pixels of the destination
image are mapped on to the pixels in the source image. In order to know how each pixel moves
between the destination and source image, only few of the important pixels are mapped. The motion of
the other pixels is obtained by extrapolating the information of the control pixels. These control pixels
are specified as lines in one image and are mapped onto the lines in the other image, or the points from
one image are mapped onto the points in the other image.

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