Images in this format have the same .jpg file extension, but a hidden piece of data called an HDR enhancement map is added. This data tells the device how to enhance the brightness, contrast, and color of the image.
Ultra HDR images can be viewed on any device capable of playing JPEGs, but they look different depending on the type of display. On a standard SDR display, Ultra HDR images look like regular JPEGs because the HDR gain map is ignored. But on an HDR display, Ultra HDR images look much better because the HDR gain map is used to create more realistic pictures.
How Ultra HDR works
Standard HDR photos use a process called tone mapping, which allows you to combine multiple images taken at different brightness levels. However, this method has a significant drawback - HDR photos look unnatural, over-processed.
Ultra HDR differs from HDR in that it does not use tone mapping. Instead, it uses gain maps - special data that tells the camera how to adjust the brightness of each pixel in the image. Because Ultra HDR is a new format, some operating systems, browsers, and applications do not yet support it.