Tag Archives: transparent

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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Make transparent button images in C#

Posted on August 2, 2017 by Rod Stephens

It seems like I keep writing this program because I need to make button images fairly often. I wanted to use a simple image with a transparent background for a button image. Unfortunately MSPaint doesn’t know how to save images … Continue reading →

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Make light pixels transparent in an image in C#

Posted on February 7, 2017 by RodStephens

Recently I had an image and I wanted to make all of the light pixels transparent. Ideally I could simply make the white pixels transparent, but the image was scanned so few of the pixels were pure white. What I … Continue reading →

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Make a tool that creates PNG files with transparent backgrounds in C#

Posted on January 4, 2017 by Rod Stephens

When you use the File menu’s Open command, the following code lets you select a image file. // The image. private Bitmap Bm = null; // Offset for displaying the image. private const int Offset = 10; // Open a … Continue reading →

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Give an image a transparent background in C#

Posted on January 3, 2017 by Rod Stephens

The Bitmap class’s MakeTransparent method changes all of the pixels with a given color to the transparent color A = 0, R = 0, G = 0, B = 0. When the program starts, the following code makes the background … Continue reading →

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Adjust image translucency in C#

Posted on December 9, 2016 by Rod Stephens

The example Use an ImageAttributes object to adjust an image’s brightness in C# uses a ColorMatrix object to scale the red, green, and blue color components of an image’s pixels. You can use a similar technique to scale the pixels’ … Continue reading →

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Make a Region from non-transparent pixels in C#

Posted on September 2, 2016 by Rod Stephens

The example Make shaped PictureBoxes in C# sets the Region property of two PictureBox controls to circular regions. That works well in that example where the images are round volleyballs with transparent backgrounds, but it would be hard to manually … Continue reading →

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Remove part of an image in C#

Posted on April 25, 2015 by Rod Stephens

This example lets you remove part of an image. It lets you load an image file and then click and drag to select an area on the image. When you release the mouse, the program generates two new images: an … Continue reading →

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