How Codecs Work - Tutorial
If you work with video, it's vital to understand how codecs work and how they change your image. In this tutorial, I over all of the big concepts behind codecs, breaking it down into understandable pieces. While the nitty-gritty of compression algorithms can get complicated, all of the main ideas are quite simple.
Here's an overview of the topics covered:
- What a codec is - And how it differs from a container.
- Different types of codecs - And why I frequently use 4 different codecs on a single project.
- Bit Depth - What it means and why it matters.
- Chroma Subsampling - 4:4:4, 4:2:2, and 4:2:0, and when it becomes an issue.
- Spatial Compression and Blocking - One of the most common artefacts you see with normal work.
- Temporal Compression - Long-GOP codecs, inter-frame compression, and ALL-I codecs.
- Lossless vs. Lossy compression - How image compression differs from data compression.
- Bit Rate - How to calculate bit rates and the differences between kbps/kBps/Mbps/MBps.
- Raw - Briefly, the difference between Raw, compressed, and uncompressed video.
Take a look at the companion post on Philipbloom.net as well!