Graphics

Generating radial indicator images using C#

In one of my projects I needed to draw radial indicators for processes measured in percent. Simple images like the one shown on right. I solved the problem by creating images in C# and saving them on server hard disc so if image is once generated then it is returned from disc next time. I am not master of graphics or geometrics but here is the code I wrote.

Using ASP.NET and Jcrop to crop images online

Cropping images in ASP.NET is easy task to do if you use right tools. In this posting I will introduce how to crop images using Jcrop and System.Drawing namespace classes. What we are building is simple and user-friendly image cropping interface that also demonstrates some simple features of Jcrop. Believe me, your users will love it!

Creating squared avatar images

In one of my current projects I needed something that takes image uploaded by user and converts it to avatar image. There is requirement for avatar images: they must be 32×32 pixel squares. Here is my solution.

Resizing uploaded image

One of my readers asked for example about my image resizing routine. Here you can find example and also some notes about my code design solution.

Resizing images without loss of quality

ASP.NET provides us with System.Drawing namespace where we can find classes we can use to manipulate with images. There are many people out there who mistakenly think thatImage.GetThumbnailImage is best choice for image resizing. You can easily create crappy images if you follow the code examples in previously pointed article. In this post I will show you how to resize images without negative side effects.

How to create grayscale images on .NET

In this example we will use simple color recalculation method to grayscale images. For each pixel on image we will calculate “average color” that we write back on image. Average color is sum of current color’s red, green and blue channels integer value divided by three. This value is assigned to all three channels for current pixel.