In the middle of revising The Digital Filmmaking Handbook for the sixth time, it’s impossible not to notice that audio technology hasn’t changed much, where as every couple of years, the video landscape is completely different. There’s a big reason for this. Quite some time ago, 48K PCM audio became standard. It was considered equal to capability of human hearing and there was no real reason to keep improving the quality of digital audio. Yes, today some devices record 96K audio but most people can’t hear a difference between 48K and 96K, which is pretty unmotivating. No one’s gonna run out and replace all their gear for something that doesn’t make a noticeable difference. And it’s not just the audio sampling that makes dealing with audio easier, it’s also the fact that the file sizes have been very manageable, in regards to computing power and storage space, for a long time. So there’s no reason to have lower resolution audio or deal with proxies or anything like that (with the exception of streaming media over the internet).
Digital video is a completely different story. Every type of video (HD, 2K, 4K) offers a range of specs: frame rates, color sampling, bit-depth, data rates, image resolution, aspect ratios. Nothing is simple. But in reviewing all the technical specs for 2K and 4K digital cinema, I did notice something: video is getting simpler again. It may be true that HD was the peak of complexity, after all it had to bridge the gap between film, analog television (both the American NTSC format and the PAL format used in most of the rest of the world), and digital cinema. As a result there were many different frame rates and combinations that added up to “HD.” Digital cinema is much simpler because everything is based on 24 fps. And the trend is to shoot raw, which means compression is also getting simpler. In post, there are only 2 families of intermediary codecs being used: Apple ProRes and Avid DNx. Meanwhile, older media such as Blu-ray and HDCAM-SR are fading away, and everything is going file-based. Most films are finished with Apple ProRes codecs and then delivered as file-based masters (including DCP).
In short, it does appear that digital video is getting simpler and heading towards a stable point, much like audio. We’re not there yet but we can see the light at the end of the tunnel.
