亮度对比度按钮

亮度对比度按钮 The brightness button should actually be called the black field button, which adds offsets (increases or decreases) on red, green, and blue signals. The button is adjusted so that the display shows the black content in the picture real black. If the computer monitor, video monitor and TV receiver of poor quality of the reconstructed image, mostly because of the wrong settings button on these two causes, this article will explain how to adjust this button. The setting of this button depends on the ambient brightness. The current display devices are very stable, so there is no need to constantly adjust them. Contrast buttons, some of which are shown on PICTURE or VIDEO GAIN, which regulate the gain of red, green, and blue signals. It affects the brightness of the white input signal. Once the brightness button is set properly, the contrast button is set to get the right brightness. This article used the name "black" and "graphics", then I was involved in a name given to these buttons clear and easy to understand the sport, I'm sorry to tell you I have to give up this movement, however, I will continue to work hard to guide users and system designers use the correct label. Figure 1. The contrast button determines the brightness of the white, and also affects the median brightness near the black. A reasonably designed monitor, which controls the contrast button, does not affect the setting of the black field. As shown in the diagram, the contrast button is set at any rate, and the 0 input signal always generates 0 brightness values. Figure two brightness button, whose function is to slide the black white video signal around the horizontal axis of the power function. In this diagram, the brightness button is set too high, and the 0 video signal has already produced a certain amount of brightness, and no video signal can produce the true black: the image is covered with a layer of gray, and the contrast is decreased. Figure three the brightness button to set the correct black video signal just generates output brightness detectable minimum, in very dark observation environment, black signal reference value should produce 0 brightness, however, in the actual environment, black set signal will depend on the brightness of the environment. Figure four the brightness button is set too low. This will result in a near black signal producing a black brightness output that can not be distinguished from black. Black pictures being swallowed up, in a photograph called 'missing shadow detail', in fact, everything information is lost, not only the details. The LCD display also has buttons with brightness and contrast, but the buttons are different from the buttons on the same logo as the CRT display. For the LCD display, the brightness button mainly regulates the brightness of the background light, but the same effect for the CRT display is to adjust the contrast button. The remainder of this article applies only to CRT displays. I will illustrate the function of the button from the two opposing aspects, referring to Fig. 1. In the diagram, the X axis represents the video signal input to the display, and the Y axis represents the brightness produced by the screen surface. No matter how the brightness button and the contrast button are set, the display has the nonlinear relationship between the input signal and the output brightness. Figure 1 shows the function of the contrast button, Figure three shows the function of the brightness button. Contrast is the brightest white and darkest black ratio that can be produced. The contrast is the main factor to determine the quality of a picture: if a picture with high contrast, you will feel it than low contrast image sharpness, even low contrast images with high resolution. It is important to set the black field accurately for good contrast and picture quality. The most common problem with display pictures is the incorrect setting of the black field. Figure two shows the result of setting the brightness button too high, and figure four shows the result of setting the brightness button too low. If the display reaches the following two conditions, it shows that the settings are correct. First, the black input signal - for computers, RGB encoding [0, 0, 0], should produce true black to increase the contrast of the display. Second, the white input signal, for the computer, the RGB encoding [255255255] should produce the desired brightness. The simplest way to adjust the display is to do the following four steps sequentially: The first step is to adjust the contrast button to the minimum The first step in adjusting the display is to set the contrast button to a minimum. The second step shows a black picture Show a full black picture, you can use the screen saver. The third step is to adjust the brightness button to produce a correct black field Adjust the brightness button to a point of balance, so that the black part of the image does not produce brightness, so that the darker part of the image is darker than the black. The fourth step is to adjust the contrast button to the brightness you want Once the black field is set properly, adjust the contrast button to make the white signal produce the right brightness. Some poorly designed display contrast adjustment button in the black field will change, then again to adjust the brightness of the button to get the right black field after adjustment after contrast display button, some even need to repeatedly back and forth between the contrast and brightness adjusting button button several times to get the correct and appropriate black field the brightness. For monitors and TVs with traditional name buttons, first adjust the brightness button to get the correct black field to increase the contrast, and then adjust the contrast button to get the right brightness. Now you see why the modern names of these buttons are 'black fields' and' images', and it is best to identify these buttons with easy to understand icons instead of names. Unfortunately, these traditional names have been inherited by modern devices such as scanners and graphics processing software, so remember that the names of these buttons are just the opposite of what they do.