Convert Pixel Image to Another Unit of Length
Converts a pixel image to another unit of length.
## S3 method for class 'im': rescale(X, s, unitname)
- Pixel image (object of class
- Conversion factor: the new units are
stimes the old units.
- Optional. New name for the unit of length.
This is a method for the generic function
The spatial coordinates of the pixels in
will be re-expressed
in terms of a new unit of length that is
s times the current
unit of length given in
(Thus, the coordinate values are divided by
while the unit value is multiplied by
s is missing, then the coordinates will be re-expressed
The result is a pixel image representing the same data but re-expressed in a different unit.
Pixel values are unchanged. This may not be what you intended!
- Another pixel image (of class
"im"), containing the same pixel values, but with pixel coordinates expressed in the new units.
# Bramble Canes data: 1 unit = 9 metres data(bramblecanes) # distance transform Z <- distmap(bramblecanes) # convert to metres # first alter the pixel values Zm <- eval.im(9 * Z) # now rescale the pixel coordinates Z <- rescale(Zm, 1/9) # or equivalently Z <- rescale(Zm)