A digital camera captures images from the real world using sensors for capturing, sampling and quantization for processing the image.
Step-by-step explanation:
Digital camera's contains arrays of electronic photo detectors which are also called photo sensors used to convert light photons to electric, these absorbed photons make electron hole pairs in depletion region to capture images focused by lens.
Capturing an image from a camera is a physical process using the sunlight as a source of energy. A sensor array is used for the acquisition of the image. So when the sunlight falls upon the object, then the amount of light reflected by that object is sensed by the sensors, and a continuous voltage signal is generated by the amount of sensed data.
In order to create a digital image , we need to convert this data into a digital form. This involves sampling and quantization which results in an two dimensional array or matrix of numbers which are nothing but a digital image.