Summary of pixels and resolution

1、Pixels: The total number of pixel points in each photo determines the actual size of the photo.

2. Common resolution = screen resolution = pixels = total pixel points per photo (frame) (for example: 1920*1080=2 million pixels, 4k video = 3840*2160=8 million pixels), the resolution we generally talk about is the total pixel points.

3. Accurate resolution: The density of the pixel points of the photo is the pixel density, the pixel value per unit length. Generally, it is expressed in how many dots per inch.

4. The video frame rate corresponds to the screen refresh rate (such as the video frame rate of 30fps corresponds to the screen refresh rate (such as 30fps <=60HZ). The video frame rate is generally greater than 16 frames and is visually coherent. If it is greater than 24 frames, the picture quality is acceptable and there is no lag. If it is greater than 30 frames, the picture quality is smoother.)

5. The stuttering of 4K videos has nothing to do with the video frame rate and the screen refresh rate, and has to do with the common resolution.

6. The pixel value of the camera, like the common resolution, represents the total number of pixel points in each (frame) photo.

7. Generally speaking, 1080p video = the total number of pixel points in each (frame) photo of the video = 1920*1080=2k.

Generally speaking, 4k video = the total number of pixel points of each (frame) photo of the video = 3840*2160=4k.

Generally speaking, the 1080p screen resolution = the maximum total number of pixels supported by the screen = 1920*1080.

Here are the clarity of several different formats:

Standard definition: 480x320, 640x480
HD: 1024x720p
(Interlaced) also belongs to HD: 1920x1080i
Full HD: 1920x1080p
Ultra (High) Clear or 4K: 3840x2160, 7680x4320
Nowadays, the video recording of mobile phones is generally 1280*720 high-definition video

8. The function of high pixels is:

a: Printing photos of super-large size is clear enough. The phone screen is only about 6 inches, and 12 million pixels is already very enough.

b: From high-pixel mobile phone photos (such as 3120*4160=13 megapixels) to low-resolution mobile phones (such as 1920*1080=2 megapixel resolution) or computer screens, the process has undergone a reduction process (the reduction process will reduce the number of pixels, but will increase the sharpness of the picture), so the function of high-pixels is that when the photo is enlarged, the photos will still be very clear and the picture details will still be very good.

Note: The photos we actually see on the mobile phone screen or computer screen are reduced images. Because the actual size is larger than the maximum display size of the screen resolution, it can only be reduced. Therefore, 12 million pixels are actually very enough, because the maximum screen resolution of mobile phones now supports 4.26 million pixels (6 inches) (Samsung s8:2960*1440), and the most common screen resolution of computers is only (1920*1080=2 million pixels), and the laptop is still 15.6 inches. And the picture quality of general videos is much smaller than the picture quality of photos. The image quality of each frame of mobile phone recording is generally 1280*720=92 million pixels.