vmag − magnifies, changes the size of a VisionX image

vmag [if=infile] [of=ofile] [m=x[,y]] [-i] [-v][-f]

Vmag changes the size of a VisionX image by bilinear interpolation. The default magnification factor is 2.0 in each dimension. Reductions can be achieved by using a magnification of less than one. Closest pixel interpolation can be selected with the -i option.

All numeric valued image types are accepted by vmag. For color map images see the -i option below.

m=x[,y]

explicitly specifies the magnification value. If only one value is specified it is used for both spatial dimensions. If two values are provided the first is for the x dimension and the second is for the y dimension.

-v

selects the verbose mode and prints some information about its action.

-i

selects the nearest integer (coordinate truncated) pixel instead of bilinear interpolation. This method has the advantage that no new pixel values are generated. This mode is automatically selected for color map (VX_PIDX) images.

-f

Forces all output images to be floating point independent of the input pixel type.

The current implementation uses floating point operations for all data types which makes it rather slower than it should be in some cases; however, the final result is correct.

A. P. Reeves