PUBLIC MARKS with tags color & pixel

Using Paper.js you can easily work with the colors of individual pixels of Raster items.

When using GDI+ method you can optimize the process of bitmap manipulation  seven  times.I am implementing an image scaling algorithm at my University Seam Carving . While working on this project I realized that simply accessing pixels by the GetPixel and SetPixel methods is too slow.

The Bitmap class has GetPixel and SetPixel methods that let you acquire and change color of chosen pixels. Those methods are very easy to use but are also extremely slow. My previous post gives detailed explanation on the topic, click here if you are interested. Fortunately, you don’t have to use external libraries (or resign from .NET altogether) to do fast image manipulation. The Framework contains a class called ColorMatrix that lets you apply many changes to images in an efficient manner. Properties such as contrast or saturation can be modified this way. But what about manipulation of individual pixels? It can be done too, with the help from the Bitmap.LockBits method and the BitmapData class… A good way to test individual pixel manipulation speed is color difference detection. The task is to find portions of an image that have color similar to some chosen color. How to check if colors are similar? Think about color as a point in three dimensional space, where axis are: red, green and blue. Two colors are two points. The difference between colors is described by the distance between two points in RGB space.