LED electronic display has become a new medium for transmitting information in our lives. It not only shows people colorful pictures, but also has the effect of beautifying the city. So how does the LED electronic display display various information such as text, graphics, animation, images and video programs?
Because light-emitting diodes are semiconductor components, the switching time is calculated in seconds, there is no memory function, the display area is large, and the signal transmission distance is long. And it cannot be manufactured by the most advanced COG, SOB and other large-volume circuit methods. Therefore, LED screens are more difficult than other flat-panel displays in terms of driving, reducing power consumption, improving efficiency, color restoration and consistency. LED electronic display is a digital flat-panel display. It has two ways to process image signals:
The first: multimedia method, usually called synchronous screen method.
This method is to capture TV signals with ordinary multimedia cards, and perform modulation, filtering and tone separation. Then the image signal is compressed by MPEG encoding after A/D conversion for storage. When we stop playing, we need to decompress it and then play it directly on the computer monitor.
The signal transmitted to the large screen is obtained from the computer’s DVI interface or graphics card through a dedicated interface card, and some processing must be performed on the interface card. At this time, the large screen is theoretically equivalent to the computer monitor or part of it, usually called a window, which can achieve one-to-one synchronous display. Since the computer monitor is scanned line by line, if the transmission signal is not processed by frame extraction and line extraction, the display format of the large screen will be the format of the monitor.
The second method: using a dedicated large screen signal processor.
The LED special-shaped screen converts the interlaced TV signal into a progressive scan signal after processing, and then plays it on the LED electronic display screen. The high-performance processing function can process more than 10 bits. When performing scan conversion, interpolation calculations, motion prediction and compensation, and scan conversion must be performed. Nowadays, large LED screens also use this method, and more image signal processing is performed, trying to upgrade the signal to the broadcast level, and of course the effect is better. Computer images must also be processed by this processor and then transmitted to the large screen for display.
The large-size rear projection TVs and plasma large-screen TVs we are familiar with all widely use this method, and the effect is much better than that of ordinary TVs. In this case, the output signal is usually depicted in the transformed signal format, which appears more accurate.
How can the full-color LED display become more high-definition? The following four tips can make the ED full-color display more high-definition!
1. Improve the contrast of the full-color LED display: Contrast is one of the key factors affecting the visual effect. Generally speaking, the higher the contrast, the clearer and more realistic the image, and the brighter the color. High contrast is of great help to the clarity, detail expression, and grayscale expression of the image.
2. Improve the grayscale level of the full-color LED display: The grayscale level of the LED display refers to the brightness level that can be distinguished from the darkest to the brightest in the brightness of a single primary color. The higher the grayscale level of the full-color LED display, the richer the color and the more colorful the color; on the contrary, the display color is single and the change is simple. The improvement of the grayscale level can greatly improve the color depth, making the display level of the image color increase geometrically. At present, many full-color LED display manufacturers can make the grayscale level of the display screen 14bit~16bit, making the image level resolution details and display effect more delicate, realistic, and colorful.
3. Reduce the dot pitch of the full-color LED display: Reducing the dot pitch of the full-color LED display can greatly improve the clarity of the display screen, because the smaller the dot pitch, the higher the pixel density per unit area of the full-color LED display, the more details can be displayed, and the more delicate and realistic the picture display is.
4. The full-color LED display is separated from the video processor: The LED video processor can use advanced algorithms to modify the signal with poor image quality, perform a series of processing such as deinterlacing, edge sharpening, motion compensation, etc., to enhance the image display details and improve the picture display quality. The video processor image scaling algorithm is used to ensure that the video image maintains the clarity and grayscale level to the greatest extent after scaling. In addition, the video processor is required to have rich image adjustment options and adjustment effects to process the image brightness, contrast, and grayscale to ensure that the full-color LED display outputs a warm and clear picture.
