Category Archives: image processing

Clip an image to a polygon in C#

Posted on January 16, 2020 by RodStephens

This example lets you select a polygon and then uses it to clip an image to it. It uses the technique described in my previous post Build a polygon selector class in C# to let you select the polygon. The … Continue reading →

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Arrange images on the corners of a polygon in C#

Posted on January 5, 2020 by RodStephens

This post shows a way to arrange images on top of a background image as shown in the image above. How to Use the Program Enter the names of the background and foreground image files, or use the File menu’s … Continue reading →

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Make an improved diagonal picture montage in C#

Posted on December 26, 2019 by RodStephens

My earlier example Make a Pinterest-style diagonal picture montage in C# showed how you could make a picture montage showing parts of images rotated by a desired angle. While using that program today I found a small bug. The areas … Continue reading →

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Draw an image spiral in C#

Posted on October 27, 2019 by RodStephens

This example lets you draw image spirals similar to the one shown above. This example lets you draw image spirals similar to the one shown above. It’s mostly just for fun, although it does include a useful exercise in graphics … Continue reading →

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Crop images to specific sizes in C#

Posted on October 8, 2019 by RodStephens

Sometimes I need to crop images to specific sizes or aspect ratios. For example, the following list shows some recommended image sizes for Google Business. Profile image – 250×250 pixels Cover photo – 1080×608 pixels Shared images – 497×373 pixels … Continue reading →

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Draw on top of a background image in C#

Posted on October 5, 2019 by RodStephens

Drawing on a background image is actually very easy. It seems to be a common question on the internet, however, so I decided to make this example. This example draws on a background image in two ways. If you just … Continue reading →

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Make a Pinterest-style diagonal picture montage in C#

Posted on September 18, 2019 by RodStephens

This example was inspired by a picture montage generated by Pinterest. Several months ago, my girlfriend and I started a bakery (see the website here), and a cool image appeared on our Pinterest page (which is here). Pinterest had taken … Continue reading →

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Give an image an improved transparent background in C#

Posted on July 3, 2019 by RodStephens

This example lets you make some pixels in an image part of a transparent background. Use the File menu to open an image file. When you click on the original image on the left, the program converts pixels that have … Continue reading →

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Make an image with rounded corners and a transparent background in C#

Posted on June 27, 2019 by RodStephens

Recently I wanted to make an image for a gift card that had rounded corners. Unfortunately the Graphics class does not have a method to draw rectangles with rounded corners. Fortunately, I have already described the key method in my … Continue reading →

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Add a watermark to all of the files in a directory in C#

Posted on June 26, 2019 by RodStephens

I recently wanted to make a slide show where each picture displayed a logo or watermark. File Explorer can easily play a slide show. Simply follow these steps: Browse to the folder containing the images. Click one of the image … Continue reading →

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