Template Detection for an Image Undergoing STIRMARK Distortions
This animated sequence of 122 images shows the effects of STIRMARK images distortions (upper image) on the detection of our embedded Mellin monomial template shown in the Fourier-Radon correlation space (lower image).  The vertical axis is Radon orientation angle.  The horizontal axis is radial position.

The STIRMARK sequence of frames is:
  • X and Y aspect ratio changes         [17]
  • Colour saturation from 0 to 2          [17]
  • Gamma change from 0.3 to 2.0      [18]
  • JPEG quality factor from 100 to 5   [19]
  • Uniform noise from 0 to 50% peak  [17]
  • Rotation +/- 5 degrees                     [17]
  • Scaling from 0.60 to 1.64                 [17]

Note how the four main correlation peaks remain visible for almost all distortions.  Only when the image is of such poor quality (and essentially unusable) does the correlation fail: specifically very high JPEG compression and very high noise.

The gamma of the correlation image has been set to 0.5 to enhance the low level background (otherwise invisible).

Sequence takes 61 seconds to complete.
Image dimensions 700x450.
Correlation image  700x700.
GIF image size 27MB.