Image Transformation is the process of changing the coordinate system of an image by resizing, rotating, etc. These operations have various applications, e.g, medical image registration.


(v1.0) pkg> add ImageTransformations

Key functions

The exported functions in this package include

  • restrict for 2-fold down sampling
  • imresize for arbitrary resizing
  • imrotate for image rotation
  • warp for general image warping, and related functions
    • WarpedView
    • warpedview
    • InvWarpedView
    • invwarpedview

These functions all have docstrings that give more details about their usage.

There are in-place version of many of the functions, e.g., imresize! etc.


  • Resize
using ImageTransformations, TestImages
img = testimage("mandrill")
img_small = imresize(img, ratio=1/8)
img_medium = imresize(img_small, size(img_small).*2)

Resulting images (small and medium): img_small img_medium

  • Warping
using ImageTransformations, TestImages, CoordinateTransformations, Rotations

img = testimage("camera");

# define transformation
trfm = recenter(RotMatrix(pi/8), center(img));
imgw = warp(img, trfm);

Resulting image: img_warp