C ++ image processing class library

Ijg JPEG library,Libjpeg

Libpng

LibTIFF

Giflib is
C-language GIF Image Processing library. Supports reading and writing GIF images.

If you need to process a type of image format separately, the above class library is a good choice. If there are many formats to process, the following class library is a good choice.

ImageMagick

ImageMagick is a software used to create, edit, and synthesize images. It can read, convert, and write images in multiple formats. Image cutting, color replacement, application of various effects, image rotation, combination, text, straight line,
Polygon, elliptic, curve, attached to the image for stretching and rotation. ImageMagick is a free software: all source code is open and can be freely used, copied, modified, and released. Supports most operating systems. Many command line tools are very useful.

Freeimage

The C language system ensures the high speed of pointer operations, and contains a variety of advanced interpolation algorithms.
In addition, unique meta EXIF information can be read. The biggest feature of this library is its conciseness. It only focuses on reading and writing images of various formats, but does not display any of them. In actual programming, you still need to call the API function for display.

GD
Is an open-source image processing library that supports images in PNG, JPEG, GIF, and other formats. GD is generally used to create charts, graphs, thumbnails, and other image-related processing operations.

The
Cimg library is a powerful image processing class library. This class can be used in code to import/export, process, and display images. It is a powerful C ++ toolbox for processing images.

Diffimg
It is a simple image comparison tool that can be used to compare two RGB Images of the same size and provide comparison data for differences between the two images.

Exactimage is a fast
C ++ image processing library, unlike ImageMagick, exactimage
Allows operations on multiple color spaces and color depths; lower memory usage and CPU usage; some optimization algorithms are 20 times faster than ImageMagick, and large images are 10 times faster than ImageMagick.