Two new IP funs

Project.toml

@@ -10,7 +10,7 @@ Documenter = "e30172f5-a6a5-5a46-863b-614d45cd2de4"
 FileIO = "5789e2e9-d7fb-5bc7-8068-2c6fae9b9549"
 Franklin = "713c75ef-9fc9-4b05-94a9-213340da978e"
 GMT = "5752ebe1-31b9-557e-87aa-f909b540aa54"
-Gumbo = "708ec375-b3d6-5a57-a7ce-8257bf98657a"
+#Gumbo = "708ec375-b3d6-5a57-a7ce-8257bf98657a"
 ImageCore = "a09fc81d-aa75-5fe9-8630-4744c3626534"
 ImageIO = "82e4d734-157c-48bb-816b-45c225c6df19"
 ImageMagick = "6218d12a-5da1-5696-b52f-db25d2ecc6d1"

documentation/all_docs_ref/all_refs.md

@@ -65,7 +65,8 @@ its use requires resorting to the \myreflink{Monolithic} mode.
 |:-----|:----|:----|:----|:----|:----|:----|:----|
 | \myreflink{binarize} | \myreflink{bwhitmiss} | \myreflink{bwperim} | \myreflink{bwskell} | \myreflink{fillsinks} | \myreflink{imbothat} | \myreflink{imclose} | \myreflink{imcomplement} |
 | \myreflink{imdilate} | \myreflink{imerode} | \myreflink{imfill} | \myreflink{imhdome} | \myreflink{imhmin} | \myreflink{imhmax} | \myreflink{immorphgrad} | \myreflink{imopen} |
-| \myreflink{imreconstruct} | \myreflink{imtophat} | \myreflink{isodata} | \myreflink{padarray} | \myreflink{strel} | \myreflink{rgb2gray} | \myreflink{rgb2lab} | \myreflink{rgb2ycbcr} |
+| \myreflink{imreconstruct} | \myreflink{imrankfilter} | \myreflink{imsegment} | \myreflink{imtophat} | \myreflink{isodata} | \myreflink{padarray} | \myreflink{strel} | \myreflink{rgb2gray} |
+| \myreflink{rgb2lab} | \myreflink{rgb2ycbcr} |  |  |  |  |  |  |
 
 
 ## GDAL utility functions

documentation/utilities/imrankfilter.md

@@ -0,0 +1,47 @@
+# imrankfilter
+
+```julia
+J = imrankfilter(I::GMTimage; width::Int=3, height::Int=0, rank=0.5)::GMTimage
+```
+
+*keywords: GMT, Julia, image rank filter*
+
+Rank order filter.
+
+This defines, for each pixel, a neighborhood of pixels given by a rectangle "centered" on the pixel.
+This set of ``width x height`` pixels has a distribution of values, and if they are sorted in increasing
+order, we choose the pixel such that rank*(wf*hf-1) pixels have a lower or equal value and (1-rank)*(wf*hf-1)
+pixels have an equal or greater value. In other words, `rank=0` returns the minimun, `rank=1` returns
+the maximum in box and `rank=0.5` returns the median. Other values return the quantile.
+
+### Args
+- `I::GMTimage`: Input image. This can be a RGB, grayscale or a binary image.
+
+### Kwargs
+- `width::Int=3`: Width of the filter.
+
+- `height::Int`: Height of the filter (defaults to `width`).
+
+- `rank=0.5`: Rank.
+
+### Returns
+A new \myreflink{GMTimage} of the same type as `I` with the filtered image.
+
+Example
+-------
+
+\begin{examplefig}{}
+```julia
+using GMT
+
+I = gmtread(TESTSDIR * "assets/small_squares.png");
+J = imrankfilter(I, width=10);
+grdimage(I, figsize=6)
+grdimage!(J, figsize=6, xshift=6, show=true)
+```
+\end{examplefig}
+
+See Also
+--------
+
+\myreflink{imdilate}, \myreflink{imerode}, \myreflink{imopen}, \myreflink{imclose}

documentation/utilities/imsegment.md

@@ -0,0 +1,58 @@
+# imsegment
+
+```julia
+J = function imsegment(I::GMTimage{<:UInt8, 3}; maxdist::Int=0, maxcolors::Int=0, selsize::Int=3, colors::Int=5)::GMTimage
+```
+
+*keywords: GMT, Julia, image segmentation*
+
+Unsupervised RGB color segmentation.
+
+For more details see the docs in Leptonica's function ``pixColorSegment`` (in src/colorseg.c).
+
+### Args
+- `I::GMTimage{<:UInt8, 3}`: Input RGB image.
+
+### Kwargs
+- `maxdist::Int=0`: Maximum euclidean dist to existing cluster.
+
+- `maxcolors::Int=0`: Maximum number of colors allowed in first pass.
+
+- `selsize::Int=3`: Size of the structuring element for closing to remove noise.
+
+- `colors::Int=5`: Number of final colors allowed after 4th pass.
+
+As a very rough guideline (Leptonica docs), given a target value of `colors`, here are
+approximate values of `maxdist` and `maxcolors`:
+
+| `colors` | `maxcolors` | `maxdist` |
+|----------|-------------|-----------|
+| 2        | 4           | 150       |
+| 3        | 6           | 100       |
+| 4        | 8           | 90        |
+| 5        | 10          | 75        |
+| 6        | 12          | 60        |
+| 7        | 14          | 45        |
+| 8        | 16          | 30        |
+
+### Returns
+A new, indexed, \myreflink{GMTimage} with the segmentation.
+
+Examples
+--------
+
+This was thought as a simple example but turned out to show a bit tricky result. The image
+"bunny_cenora.jpg" is simple and we can clearly see that it has only 6 colors, so we would
+expect that `colors=6` would do the job. But in fact we need to set `colors=7` because
+the outline (black) is in fact picked as two different (dark) colors.
+
+\begin{examplefig}{}
+```julia
+using GMT
+
+I = gmtread(TESTSDIR * "assets/bunny_cenora.jpg");
+J = imsegment(I, colors=7);
+grdimage(I, figsize=6)
+grdimage!(J, figsize=6, xshift=6, show=true)
+```
+\end{examplefig}