HDR tone mapping

More and more movies are delivered in HDR, however, not all displays are optimized for HDR content. This means HDR content must be adapted to suit the display before viewing. Most HDR standards have been created with direct view displays in mind, these displays have an absolute brightness level. Projection systems were not accounted for when HDR standards were created, as the screen luminance of a projection system varies depending on screen size, distance from projector to screen (throw distance), viewing environment, and screen material. This means it’s much harder to optimize HDR content for a projector as these systems do not have a dynamic range of 1,000 nits or as the most extreme movies are released with a mastering nits value of 10,000 nits.

In projectors and other displays with limited brightness, the adaption requires processing. Content in movies already are edited for optimal viewing, the display adaption is aimed to preserve the Director’s intent to the extent of the displays technical capabilities. For most manufacturer this means they must launch new projectors, either because of limited processing power, or because they are use off the shelf processing.

Barco Residential do neither, we continue to offer our customers FW upgrades. Looking back at the customers that bought a Pulse platform product almost a decade ago, they will receive, thanks to the processing power these projectors have, a FW upgrade that will completely change the way we display HDR content. We have turned our color and light processing upside down and pushed what we did not think was possible to a completely new level.

To achieve this, we had to, not only update the SW, but the actual SW that is controlling the HW, also called FPGA. These updates reside deep within the core of the projector.

Given the absolute property of the PQ curve, the HDR video signal should be displayed at the encoded brightness. The problem is that very few displays can produce 10 000 nits or even 1000 Nits. Therefore, the image signal must be adapted and scaled to fit the target display. The simplest method would be scaling and clipping the image above the maximum output level. This results in blown out details and hue shifts. (picture left and middle) To properly adapt the image, tone mapping should be used (picture to the right).

After installing the new Pulse firmware in our demo Bragi CS, I had to smack my head to make sure I was not dreaming... 

this new update has completely changed the game when it comes to HDR performance. It is NEXT level, and my mind has been blown. The improvements in image quality cannot be described, it needs to be seen.

What is even more impressiveness is how this confirms your approach to how you build your projectors! All of that was done with software and can work with older machines we sold years ago. Again, mind blowing!!!

Well done Barco.

Ryan Donaher

Tone mapping has multiple forms, however, the idea is to apply a curve to the image, compressing the highlights. While this can be applied directly to the RGB channels, it is recommended to use a perceptually uniform color space such as ICtCp. That is our starting point.

 

The next enhancement we looked into was black level, this is why we created DynaBlack. DynaBlack is at the moment only released on Hodr and Njord, but will soon also be available in our other Pulse products via FW upgrade. Why is DynaBlack important when we talk about HDR?

HDR is about dynamic range and DynaBlack increases the dynamic range of the projector, making the difference between a darkest scenes and the brightest scene greater. With Dynablack we increases the Dynamic range of a projector by up to 1000%.

I had to pinch my arm to check if it was real. Barco’s HDR tone mapping does a fantastic job!

Njord is the best DLP projector I have ever tested. For the first time I had a real HDR experience with proper brightness and color volume, with 240 calibrated nits and 99% DCI-P3 coverage on a 5m wide micro-perf (Gain 0.9) screen.
I had to pinch my arm to check if it was real. Barco’s HDR tone mapping does a fantastic job, even in challenging movie scenes where other LCoS/LCD projectors couldn’t render all details, the Barco Residential projectors showed every little detail.

I didn’t expect DynaBlack to work as well as it did with the tone mapping implementation either, but it is the best light-dimming implementation I have ever seen in a projector, I measured 23,000:1 in dynamic contrast. The Njord CS is worth every cent, it is like having an OLED experience on a giant screen.

Chris Makovets

To go even further we created a feature called Contrast enhancement that increases the black level within the darkest part of a scene. If you combine all these enhancements with content meta data, the screen luminance content threshold data and our new SEIDR technology you get an amazing HDR image.

Our goal is always to envelop movie connoisseurs with an exceptional film experience from within the comfort of their living spaces. Our new HDR tone mapping algorithm combined with SEIDR does exactly that. This feature brings HDR content to life as intended and ensures predictable, truly seamless outcomes, by combining smart engineering, amazing technology with smooth and efficient operations for an unparalleled experience.

SEIDR Technology

In Old Norse, SEIDR was a type of sorcery practiced in Norse society during the Late Scandinavian Iron Age. The practice of SEIDR is believed to be a form of magic relating to both the telling and shaping of the future.”

This is what we do in our projectors as we always minimize the latency in everything we do. Other manufacturers of projectors or video processors add several frames latency via their tone mapping, contrast enhancements, frame interpolation or other image processing. However, if your processing power is fast enough and the algorithm is smart enough, you can predict the next frame and in real time update and optimize the content, instead of reading the next frame and introduce latency. Therefore we created SEIDR.

Manufacturers alwaysprioritize new over old. It is a testament to the Barco Pulse platform visionand capabilities that new innovations can be leveraged by products shipped over5 yrs ago. I have now downloaded the entire Game of Throne series onKaleidescape - this time I will be able to see what I missed the first time!Barco truly hit this one out of the park!!  

I have been selling, calibrating, and using high-end projection systems in my business and in my personal screening room for more than 25 years. It's exceedingly rare that I encounter a visual experience so unique that it makes me do a double take, especially when all I did was a ten minute firmware update. I did not spend hours tweaking and calibrating only to wonder if the change made a big enough difference that anyone would readily notice.

On the contrary, after loading the latest tone mapping firmware in our reference Njord CS theater, the visual improvement was immediately obvious to me and everyone else. The improvement was so profound I started playing all of the demo material I have in my arsenal to evaluate highly bright sky scenes, very colorful well lit scenes, and very dark scene performance.

This update is indescribable; if I didn't perform the update myself, I'd be incredulous. All I can say is that I spent two hours watching every scene "for the first time", and I was NOT adjusting settings to compensate for different content Mastering Luminance levels as I have done in the past. I've never witnessed this level of accuracy over such a wide gamut of content.

Jeff Galea
Boca Tech and Automation