ACADEMY BLACKMAGIC RAW
RAW MAGIC?
BLACKMAGIC’S RAWRESPONSE The Aussie camera firmhits back at criticism about CinemaDNGwith its very own Raw standard
WORDS ADAM GARSTONE
H ot on the heels of Apple and Atomos revealing the ProRes Raw format, Blackmagic has released a new Raw format for its cameras. Blackmagic Raw (BRAW) is a compressed format in the company’s cameras, alongside the CinemaDNG – a format that has not been universally applauded. CinemaDNG has a couple of issues that cause problems in post-production. First, when you roll the camera, it produces a folder full of files – each file being a frame of the clip. Some post-production tools – including Blackmagic’s own DaVinci Resolve – can understand this structure, but plenty can’t. The second issue is one inherent in Raw files. The data in a Raw file comes straight from the camera sensor, so whatever you are using to view those images must understand something about the sensor and how to convert the data into usable video. Again, all this processing is built into DaVinci Resolve, but few other software packages produce acceptable quality pictures.
“It’s fairly straightforward to come upwith a format that contains all the frames in a single file”
ABOVE If you are comfortable working with DaVinci Resolve then using it for Blackmagic Raw files is simple and speedy
spectrum. This means you have to ‘invent’ blue and red pixels to combine with each green pixel to produce the final output. In fact, there are myriad techniques used tomake the final image look as good as possible – and they all tax the capabilities of even the fastest computers. Blackmagic’s approach is to have the new Raw file format contain partially decoded information. There aren’t any technical details available at the moment, but it sounds very clever indeed. As well as simplifying the decoding task, Blackmagic’s software decoder uses the special instructions available inmodern CPUs and GPU acceleration to speed up playback. The upshot is that BRAWwill play
So, Blackmagic set out to solve these issues – and a fewmore besides... Of course, it’s fairly straightforward to come up with a format that contains all the clip’s frames in a single file. Similarly, file format can currently embedmetadata that tells the decoding software about the characteristics of the camera sensor. But the engineers at Blackmagic realised that they had an opportunity to introduce even more additional benefits. Traditionally, decodingRawfiles is slow–mostly because of the complexity required to de-Bayer the sensor data. The sensor has a matrix of red, green and blue pixels – usually with twice as many green pixels as red and blue, because our eyes are more sensitive to the green part of the
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PRO MOVIEMAKER SPRING 2019
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