Gamma correction in LED display, also known as gamma correction or gamma nonlinearization, is an image processing technology used to adjust the brightness and contrast of images on LED display screens to make them present more accurate and natural colors under different display conditions.
This technology corrects the nonlinear characteristics of display devices by changing the brightness value of each pixel in the image, thereby improving the visual effect and viewing experience of the image.
The purpose of gamma correction
1. Correction of nonlinear characteristics: There is often a nonlinear relationship between the brightness response and input signal of traditional display devices (including early CRT displays and modern LCD and LED displays).
Through gamma correction, this nonlinearity can be compensated so that the image is closer to the true color of the original signal when displayed.
2. Optimize visual effects: Gamma correction can adjust the brightness and contrast of the image, making the dark details clearer, the bright parts not overexposed, and the overall picture more vivid and natural.
3. Adapt to different display devices: Since LED display screens of different brands and models may have different brightness response curves, gamma correction can ensure that the image presents a consistent effect on different display devices.
Gamma correction method
The gamma correction method is mainly achieved by nonlinearly transforming the brightness value of each pixel in the image. The specific steps are as follows:
1. Understanding the gamma value: The gamma value is a nonlinear parameter used to describe the brightness response curve of the display device. Generally, the gamma value is between 0.5 and 2.5, where 1.0 represents a linear response.
2. Image preprocessing: Convert the image from the RGB color space to the linear space for better correction. This usually involves color space conversion for each pixel of the image.
3. Gamma transformation: Apply the gamma transformation formula to the brightness value of each pixel in the image. This formula is usually output = input ^ (1 / gamma), where input represents the brightness value in the input image, output represents the corrected brightness value, and gamma represents the gamma value.
4. Image post-processing: Convert the corrected image from the linear space back to the RGB color space for final display or storage.
Application of gamma correction
In the field of LED display screens, gamma correction is widely used in various display scenarios, including outdoor advertising, indoor meetings, live broadcasts of sports events, etc. Gamma correction can ensure that the image can present the best visual effect under different lighting conditions and different viewing angles.
Notes
1. Only do one correction: During the gamma correction process, make sure to correct the image only once. Multiple corrections may cause image quality degradation, such as overbrightness, color resolution loss, etc.
2. Adjust the gamma value according to the display device: Different display devices may require different gamma values to achieve the best effect. Therefore, when performing gamma correction, it should be adjusted according to the actual display device used.
3. Consider the human eye perception characteristics: Gamma correction should also consider the human eye's perception characteristics of brightness and contrast to ensure that the corrected image is more in line with the human eye's visual habits.
In summary, gamma correction in LED display screens is an important image processing technology that optimizes the display effect and improves the viewing experience by adjusting the brightness and contrast of the image.