Why do pictures have the same resolution, but different clarity and quality?

Why is the difference so big? Because it's not entirely because of the difference of 40 pixels. In fact, it is because the picture of 1040 was stretched once for full screen display. Although it has only been pulled so far, it is enough to pull the picture quality out of the obvious gap. In fact, if you display two pictures at the ratio of 100%, the only difference is the original image quality of the two videos.

The clarity of a picture is related to the resolution, but it does not depend entirely on the resolution. As mentioned above, the difference between the previous photographic equipment and photography technology will also be reflected in the quality. For example, a SLR with the same resolution is much better than a mobile phone because of its better lens, better photosensitive chip, better body stability and better exposure parameter adjustment system. For another example, the same camera sets the resolution unchanged and the hand shakes (assuming that anti-shake is not turned on).

The definition of video is more complicated than that of pictures, because pictures are two-dimensional data and videos have a time axis, so they are three-dimensional data. Resolution is not even a good indicator of two-dimensional image quality. The amount of data on the time axis and the adoption of compression technology (almost all the videos you can see are compressed, and the original video without compression is too scary) may change your evaluation of image quality.