A graphics processing unit (GPU) is hardware similar to a central processing unit (CPU), except it is made exclusively for images and any function performed by it is known as GPU image processing. Unlike the CPU and most other image processors, GPU image processing treats every image as a three-dimensional (3D) image, even if the image is two-dimensional (2D). Complex images often have textures, and a GPU is able to load many textures at once. To get the perfect color per pixel, a GPU uses pixel shaders. There are many graphic design applications that enable users to layer images, but the GPU is optimized to load these images.
Most image processing languages and hardware split up 2D and 3D images, because different rendering and processing techniques typically are needed for both. With GPU image processing, everything is treated and loaded as a 3D image. The GPU is made in a way to treat 2D images as scaled back 3D images, which presents certain benefits. This increases the loading speed for 2D images, because the GPU is setup to handle more complex images, and 3D images can be loaded quickly because the GPU is ready to load the many factors needed for these images.
Textures are used in many images, especially those made by graphic design programs. These textures add extra details, but they also require more memory to load properly. GPU image processing is able to load around 16 textures or more at once, which increases how quickly textured images load and how quickly textures can be applied.
Each pixel in an image has its own specific color and shade, and matching this information is important when loading an image because, otherwise, the image may load incorrectly. To ensure this is done properly, GPU image processing uses pixel shaders. There typically are many shaders working at once, and each one tells the GPU exactly what color and shade is needed for each pixel.
Many graphic design programs are able to make layered images, or a composite picture made from many images layered on top of one another, but there can be a few problems when making these images if there is no GPU. A CPU is not optimized for graphics loading, so these images often take a long time to load, and the graphic design program may even lag or crash when making composite images. With GPU image processing, these images not only load quicker, but the GPU improves the image blending.