Because the brightness range of SDR display devices is much smaller than that of HDR images, and with the brightness range seen in nature including the relationship between the human eye’s perception of brightness and brightness intensity as perceived by the human eye, non-linear processing is required when designing tone mapping algorithms. Tone mapping algorithms use different processing methods, but the traditional tone mapping methods can be described by the following formulas:

Where ‘f’ represents the tone mapping operator, ‘I’ represents the image to be operated, ‘w’ and ‘h’ represent the width and height of the image, and ‘c’ represents the number of channels of the image, usually, this is RGB, meaning three channels are the most common.

Here ‘C’ and ‘c’ are the colors before and after tone mapping, respectively. ‘L’ represents the brightness of the HDR image, while ‘T’ is the corresponding brightness value after tone mapping. ‘s’ is the parameter used to adjust saturation provided s<1.

Visionular has a lot of respect for the work that goes into making films. We want to make sure that every video, no matter when it was made or what equipment it was made on, can be viewed and enjoyed to its fullest extent. While we are proud of our technology, we are always looking for ways to improve it so that every Director’s and DP’s artistic vision can be preserved for future generations.

We train the generative adversarial networks using millions of high-definition images and video sets with extended datasets. These training datasets cover a variety of content types and resolutions, which meet the super-score requirements of a multitude of scenarios.