After the much publicized launch of the Xbox One S with its new features and the information given during this week’s PlayStation Meeting, a lot of people around me were wondering what really is HDR and how does it affect gaming. To be honest, at first, I didn’t know what to answer, because the only time I’ve seen this acronym is on my digital camera and when it was on, the result of taking a picture was a much bigger file but a much clearer image. These are the results of my research.
The acronym HDR stands for High-Dynamic-Range, a technique used in imaging and photography to reproduce scenes with a much wider range of colors and luminosity, allowing for a much natural representation of an image, making the transitions from white to black a lot more natural.
In terms of digital images like what we seen on a screen of a computer or a digital TV, this is done through the way the images are coded. Digital content is stored using binary codes (zeros and ones), which can allow to store logically information when ordered in a proper way. For a long time, color information about the pixels used in an image is stored using a RGB mechanism (red-green-blue). The intent is to have the ability to recreate every color that exists through a combination of red, green and blue (a bit like we learned during our art classes in school that the colors can be recreated using red, yellow and blue). The intensity (quantity) of each color is quantified with a 8 bits digit (ranging from 0 to 255). This standard allowed creating more than 16 million colors (256 * 256 * 256), allowing to render images in a very realistic way, but still far from what the human eye can see. The level of details was considered enough though to be used in HD and full HD TVs (information taken from a French website called lesnumeriques), with their respective resolution of 1280 x 720 and 1920 x 1080 pixels.
With the explosion of home theaters, bigger and bigger TVs, and the non-stop quest for higher realism, the concept of having an even higher resolution was born, thus the creation of the Ultra HD resolution, also known as 4K. The name comes from its much higher resolution, 4 times bigger than the one of a full HD TV : 3840 x 2160 pixels. With that much precision on every image, the scope and the level of details that can be incorporated are now raising to an astronomical level. One problem remained though. The details are present, but didn’t deal with lighting effects very well. The cut between the colors were not very natural, especially during the very dark or very bright environments. The same situation happened when trying to take a picture with a digital camera. A solution was built, but for that, we needed to review a standard that was used for many years.
To be able to display all the missing tones and colors, HDR was created, allowing to colors (so, by the same fact, images) using more than the 8 bits – 255 different colors used in the older technologies. With HDR cameras, it can go to as high as 16 bits – 65536 colors now, allowing a much wider ranges of colors, allowing to store all the nuances linked to the luminosity of a scene. (An example can be seen below, with the image of the left without HDR and the one on the right with HDR.) With TVs, it raised to 10-12 bits, depending on the equipment. With this much more information about the precision of an image, the quality of the image rises drastically. Naughty Dog, the studio behind important titles like the Uncharted franchise, went as far as saying that it is HDR is the future, having an even higher impact than an improved resolution.
To make all of this information travel fast enough for a proper render on a screen, the requirements on the electronic components are much higher though, demanding more powerful machines and TVs that are compatible with those new standards.
During the PlayStation Meeting event, Sony announced that HDR capabilities will be integrated into every PlayStation 4, even with the existing ones (all 40 million of them), through a firmware update on the consoles. Tech-savvy people though were really confused though about one aspect. To be able to send images with HDR to TVs, a minimum HDMI standard must be respected, with each standard having its own requirements/speed/etc. At launch, PS4 HDMI controller was rated as HDMI 1.4, which is insufficient for HDR, demanding a minimum of 2.0. It looks like the initial evaluation was wrong.
According to an article read on arstechnica, it looks like the components of the PS4 were ready for a 4K surprise update, and he mentioned this about a year ago, when he analyzed things like motherboard schematics, exposed pins and and HDMI bandwidth ratings. It looked like Sony just needed a necessary firmware update to comply with bandwidth and copy-protection standards. This could actually be a proof that Mark Cerny was not lying when he said that they were already thinking about the Pro as soon as PS4 shipped.
So this actually means that the actual PS4 (and the slim) plugged to a proper 4K TV will actually be able to render HDR imagery. With a Pro console and its power increase (about 2.5 times higher teraflops count), you will get the 4K resolution output, with the help of some upscaling techniques. Already more than 15 games were confirmed to be compatible with the 4K output and HDR rendering.
I hope this article has clarified for you what is HDR and that it is not just a buzzword anymore. If you happened to have any questions, let me know in the comments below.
