To build a solid foundation for this chapter, as well as the next ones, we must first take some time to present the fundamental concepts of digital videos. Once again, the theory will be explained in a very practical way, using hands-on examples wherever possible.
Videos are practically created by joining several still images, called frames. The joining of the images is performed by adding an extra dimension to hold the sequence. Since, as you already know by now, grayscale images are two-dimensional and color images are three-dimensional, grayscale videos will be three-dimensional and color videos will be four-dimensional. For example, if we join 100 grayscale images of size 1080 rows and 1920 columns, we will get a matrix that is 1080 x 1920 x 100. Similarly, if we join 100 color images of the same size, the resulting matrix will be 1080 x 1920 x 3 x 100.
The most usual and natural way to create a digital video is to use a video capturing device, for example...