Why can't YouTube handle snow or confetti? Some videos look great on YouTube, but others look terrible. It could be a cheap camera, but it could also be that the creator doesn’t understand the science behind video compression.
This video demonstrates something that’s usually incredibly hard to describe: how video compression works. Compressing a JPEG image is one thing, but compressing 30 images every second is the stuff of science fiction. I think that this video explains the process rather well, because it shows us the limitations of compression.
How bad can it get?
Another limit of compressed video is that it can’t be compressed again and again without adding more noise. The video below shows us what happens when a video is compressed 1,000 times.
So, how do you make sure your video looks great on YouTube?
Without getting into massive details on intermediate formats vs delivery formats, here’s a quick video I made explaining how to compress a video using Adobe’s Premiere Pro and Encoder. No matter what software you’re using, though, the same settings still apply. This video was made with Canon DSLRs shooting 25p and will hopefully stop people from accidentally converting to interlaced video or other broadcast standards. It's not the definitive guide, because that depends on your footage.
An Advanced Tutorial
The information in my video is limited, so if anybody would like to dive deeper into the world of compression, here are two great tutorials on it. The first describes the science behind it, and the second tells you how to apply that knowledge.
Currently, the most widely used codec for compression is H.264. If you’re given a .MOV, that’s probably just H.264 wrapped in a Quicktime file. The same goes for MP4 files. In the future, we’ll start to see H.265 compression come in. The next wave of video compression will mean that we could get a video compressed to half the file size as before while retaining the same quality.
It may seem boring, but if a content creator doesn't understand codecs and compression, they may waste a lot of time getting great shots that will only look noisy in the end.