Flicker Vignette - How do I warp a gel image's geometry?

This vignette shows how do you can warp one image to the geometry of the other to make them easier to flicker compare. There are two warping transforms - affine that requires 3 landmarks and 6 for the polywarp. (The polywarp is not available yet- [FUTURE]). You first define the required number of N pairs of corresponding landmarks between the triangular region you are interested in warping. Then select the gel you wish to warp. You then apply the warp transform from the Transform menu. See the example in the Reference Manual.

Method

Defining the N landmarks

  1. Select the left or right gel image window by clicking on it. Then select one of the N landmarks you want to use by clicking on it.
  2. Select the other gel image window by clicking on it. Then select the coresponding landmark. You may have to Flicker the gels to ensure they are in fact the correct spots.
  3. Add the landmark to the landmark database by using the (Landmark | Add landmark (C-A)) or type C-A.
  4. If you do not like the landmark, you can delete the landmark from the landmark database by using the (Landmark | Delete landmark (C-D)) or type C-D. You only need to do this step if you are not happy with the landmark you just created.
  5. Repeats steps [1] through [4] until you have the N landmarks.

Warping the image

  1. Select the left or right gel image window you want to warp.
  2. Make sure that you have Checkbox onAllow transforms checkbox enabled.
  3. Make sure that you have Checkbox offSequential transforms checkbox disabled.
  4. Perform the transform you want to try in the (Transform | Affine warp) or (Transform | Poly warp) command.
  5. Reposition the transformed image and the other image to the spot of interest inside of the landmark region.
  6. Enable flickering. It should be now easier to see the corresponding spots.

Setup for the demo

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