_modules/filter_difference_of_gaussian.md

 ---
 title:     Difference of Gaussian
-layout:    page
+layout:    module
+prerequisites:
+  - TODO
+objectives:
+  - TODO
+motivation: >
+  TODO
+concept_map: >
+  graph TD
+    IM("Image") --> SBl("Small blur")
+    IM --> LBl("Large blur")
+    SBl --> NF("Noise filtered")
+    SBl --> SBlLBl("Small blur - Large blur")
+    LBl --> SBlLBl
+    LBl --> LB("Local background")
+    SBlLBl -- gives --> DoG("Differece of Gaussians (DoG)")
+    DoG -- is related to --> LoG("Laplacian of Gaussian (LoG)")
+
+# figure: /path/to/image.png
+# figure_legend: TODO
+
+activity_preface: |
+  - Open image: xy_8bit__two_spots_noisy_uneven_background.tif
+  - Appreciate that you cannot readily threshold the spots
+  - Compute DoG:
+    - Copy image and blur with a Gaussian of small sigma -> Gs
+    - Copy image and blur with a Gaussian of bigger sigma -> Gb
+    - For the official DoG: `rb = sqrt(2) * rs`
+    - Create `DoG = Gs - Gb`
+  - Appreciate that now it is possible to threshold the spots in the DoG image
+
+activities:
+  # "TODO": /path/to/activity/file.md
+
+exercises_preface: >
+
+  TODO
+
+exercises:
+  # "TODO": /path/to/exercise/file.md
+
+learn_next:
+  - TODO
+
+external_links:
+  - "[Wikipedia: Difference of Gaussians](https://en.wikipedia.org/wiki/Difference_of_Gaussians)"
+  - "[FeatureJ: plugins for feature extraction from images](https://imagescience.org/meijering/software/featurej/)"
+  - "[CellProfiler module for enhancing/suppressing features in an image (Python)](https://github.com/CellProfiler/CellProfiler/blob/master/cellprofiler/modules/enhanceorsuppressfeatures.py#L4)"
 ---
-
-## Difference of Gaussian (DoG)
-
-<img src='https://g.gravizo.com/svg?
- digraph G {
-        shift [fontcolor=white,color=white];
-        image -> "small blur";
-        image -> "large blur";
-        "small blur" -> "noise filtered";
-        "large blur" -> "local background";
-        "small blur" -> "small blur - large blur" -> "DoG";
-        "large blur" -> "small blur - large blur" -> "DoG";
-        "DoG" -> "Laplacian of Gaussian (LoG)" [label="  is related"];
-}
-'/>
-
-### Activity: Enhance spots in noisy image with uneven background
-
-- Open image: xy_8bit__two_spots_noisy_uneven_background.tif
-- Appreciate that you cannot readily threshold the spots
-- Compute DoG:
-        - Copy image and blur with a Gaussian of small sigma -> Gs
-        - Copy image and blur with a Gaussian of bigger sigma -> Gb
-                - For the official DoG: `rb = sqrt(2) * rs`
-        - Create `DoG = Gs - Gb`
-- Appreciate that now it is possible to threshold the spots in the DoG image
-
-### Learn more
-
-- https://imagescience.org/meijering/software/featurej/
-- https://en.wikipedia.org/wiki/Difference_of_Gaussians
-- https://github.com/CellProfiler/CellProfiler/blob/master/cellprofiler/modules/enhanceorsuppressfeatures.py#L4
-
-