Again, another tutorial for paint.net. I will teach you how to easily crop a picture. We start from this nice picture representing arms linked over a lawn. Thanks to the technique exposed below, you will be able to isolate arms. This technique can be reused to crop objects and people from the background on a photo.
To perform this tutorial, you will need the « feather » effect plugin. To install it, just uncompress the .dll file in the effects directory of your paint.net insallation folder and then relaunch paint.net so that it can initialize with the plugin.
The cropping technique is essential in order to perform complex merges from different pictures. So it is important to undersand and manage it.
The idea there is to make the lawn disappear. Here is how to proceed :
1/ Duplicate the layer (Ctrl + Shift + D);
2/ Select the newly created layer;
3/ Use the extract channel effect with the following parameters : HSV – Hue (Effects menu > Color > Extract Channel);
4/ Use the magic wand (S) in global flood mode (earth icon);
5/ Adjust tolerance to 40%;
6/ Click on the « green » area of the picture, this will select the biggest part of the green area on the picture;
7/ If the selection isn’t perfect (green parts not selected) : press the Ctrl key and click on the missing parts to select these;
8/ Select the bottom layer;
9/ Press the Suppr key;
10/ Select the top layer and delete it;
11/ Use the feather effect with the following values : Amount 4, Strength 4 and Shrink.
That’s it, nice work, isn’t it?
By looking at the result, you can feel it is a bit too aliased. This is especially true because of the white background. For a cleaner result, you can use the outline effect (Effects menu > Object > Outline). This will give you the following result :