Image Acquisition is the first step in any image processing system.

The general aim of any image acquisition is to transform an optical image (real-world data) into an array of numerical data which could be later manipulated on a computer.

Image acquisition is achieved by suitable cameras. We use different cameras for different applications.

If we need an X-ray image, we use a camera (film) that is sensitive to X-rays. If we want an infrared image, we use cameras that are sensitive to infrared radiation.

For normal images (family pictures, etc.), we use cameras that are sensitive to the visual spectrum.