Creating a sketch effect out of your photo #GIMP

I found a tutorial that makes a photo looks like a painted sketch.  Honestly, I was unable to achieve his final output but I was able to discover something else.  My picture still looks like a sketch but is somewhat different.  Let’s begin!

1. Choose an image that you want to convert into a sketch.  I chose a picture of me stuck in a traffic. lol…

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2.  Right click on the original image and select duplicate layer.  Then we will apply a Sobel Edge Detect on the duplicate layer.  Right click on the image then select Filters -> Edge-Detect -> Sobel.

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3.  Afterwhich, we need to bring out the detail with the auto-equalize and then convert it to grey. To do this, select Colors -> Auto -> Equalize then Colors -> Desaturate to make it grey.  Rename the layer to Equalized Edge.

Auto Equalized

Desaturated

4. We need to eliminate edges with small magnitude and keep the strong edges.  The way to do this is through the Curves tool.  Duplicate the Equalized Edge layer then right click on the image then select Colors -> Curves. Set the curve type to free (which allows discontinuities),  and then for the bottom 3/4 of the curve (or thereabouts) to 0.  Drag the mouse/pen along the bottom of the curves tool.  Rename the layer to Highpass.

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after the highpass

5.  Then duplicate the Equalized Edge layer and name it Masked layer. Make sure it is placed above the Highpass layer.  Right click on it then select Colors -> Invert.  Select the Highpass layer, click Edit -> Copy. Go back to the Masked layer then right click on it and select Add layer mask.  Select the mask and click Edit -> Paste. Hide the Highpass and Equalized Edge layers by clicking on the eye icon beside the layers.  Your layers should look like the one below.

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You should have something like the one below.

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You now have a sketch effect. You can already stop at this point if you already like what you got.  But if you want a colored sketch effect, then add a new layer and place it above your original image. Then change the mode (found above the layers dialog box) from normal to overlay. You should have something like this.

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So we now have two sketch effects!  Hope you like them!

Or you can also have a painted sketch effect from my source.