Blu-ray Encoding At Its Best for Baraka
Blink Digital Solves Encoding Issues Shot-By-Shot
Translating the quality of “Baraka”’s imagery to Blu-ray required meticulous restoration work by Fotokem, including scanning the original 65mm film negative in 8K (the digital master was 30 terabytes of data). That was followed by a painstaking encoding process conducted by Blink Digital in collaboration with Digital Restoration Producer Chris Reyna for Magidson Films, the production company, and MPI Media Group, the US distributer of the film in Blu-ray.
We spoke with Blink Digital’s Drew Huntsman, Senior Director of Technical Operations, and Steven Chester, VP/General Manager Worldwide, about the process of scene-by-scene encoding and the approach taken to solve the range of encoding challenges.
STEVEN CHESTER: “Baraka” shows that when you put time and effort into restoration — done by Fotokem — and encoding, performed by Blink, you can create a vastly superior product. People are very impressed with “Baraka,” and some have suggested that it alone offers reason enough to buy a Blu-ray player and a flat screen television.
Drew led the project for Blink and managed our interaction with Fotokem. He also worked closely with Chris Reyna, who produced the restoration and had worked directly with the filmmakers, Ron Fricke and Mark Magidson. It was a uniquely collaborative process. For example, we found problems with three shots and communicated that to Fotokem. They made adjustments and re-rendered the shots. We received new masters and performed a new encode test. As a result, those problems were resolved before we performed the final encoding.
There is a tremendous diversity of shots in the film, ranging from high-speed, high-motion, time-lapse photography of cars moving through the streets of New York to a static shot of a seated monk, to flames rising from an oil field, to a smoldering volcano. It includes virtually every imaginable type of shot.
SC: “Baraka” is obviously a special case, but we learned a lot from working with the challenges it presented. Our goal is to take the processes and techniques we used in encoding this disc and scale them so that they can be applied to other projects. That includes projects of all types—animation, live action, whatever.
How did you test the quality of the encode?
SC: We knew that running this disc through a normal QC bay would not be sufficient. At times, we reviewed it on a 10-foot screen. We performed projection tests. We also created sub-master discs that Chris Reyna reviewed on our systems. We took them to outside sources to view with various playback configurations. We asked other experts to review the disc on high end equipment to ensure that we had maintained the quality of the restoration work.
Talk about some of the more challenges scenes.
SC: When you do a lot of Blu-ray encoding, you can easily identify problem scenes. Scenes with a lot of motion or involving a lot of data are most likely to require special attention. Fire and smoke, rippling water, high contrast shots — they all present different challenges and have to be dealt with differently. We performed tests on those shots to determine how best to deal with them. In some cases, we did some pre-filtering to make it easier to encode while retaining the quality of the picture. In other cases, we upped the data rate to allow for the greater picture quality. Sometimes it just comes down to the amount of data for a shot or scene.
One scene shows a rice paddy, which created horizontal lines while the camera was tilted. As the camera moved, artifacts would appear in the lines of rice. That is a typical problem. Another example is an opening shot of a pond. It was a high contrast shot as the sun reflects off dark areas of the water. Another shot shows a village, revealed through a fence. Similar to the rice paddy, the fence cause vertical lines that produced artifacts—and your eye was naturally drawn to them. Because there is no dialogue, problems like that really stood out. We focused a lot of attention on eliminating those types of problem that might have gone unnoticed in a conventional Blu-ray disc.
DH: One of the most challenging scenes showed a mirrored mosque. It is a shot with the camera shooting straight up into a mirrored ceiling. It wasn’t a single mirror, mind you, but rather small, 1-inch mirrors that cover the entire ceiling of the mosque. The cinematographer was walking through the mosque as he shot, so everything is moving. It was an incredibly difficult scene. We had to make a number of adjustments to make the shot work, including some proprietary processes that we developed to do some pre-processing. It turned out extremely well.
In addition to the encoding solutions, what else did you learn in this process?
SC: Most Blu-ray projects do not require so much individualized attention. Some masters require an encode test, some don’t. You make a few, general encoding adjustments and that’s that. “Baraka” required a different workflow and specific workarounds, like pre-processing, to address specific problems. We concluded that many of these techniques could be applied to other projects in order to take them to the next level.
DH: When given sufficient time and resources, when the restoration is done well, and there is good communication between the restorationist and the compressionist, you can create a product that is truly outstanding.
And the tools you used on this?
DH: We used a PSE encoder, which is a VC-1 encoder originally created by Microsoft and now being sold by Sonic Solutions. For pre-processing and filters, we used a wide variety of tools, some of which were propriety and developed just for situations like this. That is our special sauce.