Analysis of the meaning of professional terms in LED display

Gray nonlinear transformation

Gray nonlinear transformation is to transform gray data according to empirical data or some arithmetic nonlinear relationship and then provide it to the display screen. As LED is a linear device, it is different from the nonlinear display characteristics of traditional display. In order to make the LED display effect conform to the traditional data source without losing the gray level, the nonlinear transformation of gray data is generally done in the rear stage of the LED display system, and the data bit after the transformation will increase (to ensure that the gray level data will not be lost).

Now some domestic control system suppliers so-called 4096 level gray or 16384 level gray or higher refers to the size of gray space after nonlinear transformation. Level 4096 uses a nonlinear transformation technology from 8-bit source to 12-bit space, and level 16384 uses a nonlinear transformation technology from 8-bit to 16-bit. The space after the nonlinear transformation is larger than that of the 8-bit source. It is usually at least 10 digits. Like grayscale, this parameter is not bigger is better, generally 12 bits can do enough transformation.

What is the brightness identification level

The brightness discrimination level is the brightness level of an image that the human eye can distinguish from the blackest to the whitest. As mentioned earlier, the gray level of the display can be very high, reaching 256 or even 1024 levels. However, due to the limited sensitivity of human eyes to brightness, these gray levels cannot be completely recognized. In other words, many neighboring gradations of gray could look the same to the human eye. And the ability to discriminate is different from person to person. For the display, the level of human eye recognition is naturally the more the better, because the image displayed is for people to see after all.

The more brightness levels the human eye can distinguish, the more color space there is on the screen, and the more potential there is to display rich colors. Brightness identification level can be used to test special software, general display can reach more than 20 levels is a better level.

Although gray level is the determining factor of the number of colors, but it does not mean that unlimited larger is better. Because first of all, the resolution of human eyes is limited, and the improvement of system processing bits will involve the changes of system video processing, storage, transmission, scanning and other links, the cost increases sharply, but the cost ratio decreases. Generally, 8-bit systems can be used for civil or commercial grade products, and 10-bit systems can be used for broadcast grade products.