Today I learned something about the video. I’ll put it down here for your memory.
I. The nature of images
An image is a collection of pixels. What is a pixel? The English name of pixel is “Pixel”, short for “picture element”. Meaning the elements of the image, that is, tiny blocks of color, each pixel has its own independent color.
When we zoom in on the image in Photoshop, we can see clear boundaries between each pixel. So why don’t we see these boundaries in everyday images? That’s where the pixel density comes in. When the pixel density is large enough to exceed human resolution, we perceive a coherent, full picture.
Pixels on electronic devices are measured in pixels per inch (PPI/Pixels per inch), which is the number of pixels per unit of physical length. Under normal circumstances, 300ppi can make people not see the sense of granularity.
The nature of video
Video is a collection of images. These images play at a certain rate, and when they do, they create the illusion of video. You can imagine, as the speed slows down, we’re going to be looking at powerpoint; If we move too fast, we won’t be able to react. But if you tap the advantage, at this time, the human eye just can’t tell they are actually a picture, instead, the brain will automatically fill in the information gap between the images, and strengthen the sense that it is a smooth and natural image.
The rate at which this collection of images is played is called the frame rate, which is measured in frame per second, or how many frames are played per second. The higher the frame rate, the slower the playback speed, the smoother the look and feel. For most video on the web, 24 frames is the industry standard. For non-film and television videos such as news broadcast, live sports events and drama programs, the frame rate of 30 frames is often adopted. The additional 6 frames will enhance the sense of smoothness when watching.
Of course, higher frame rates are not always better, and each frame rate has its own specific purpose and application scenario.