Comment

Comment by bscphil

Interesting introduction. Too bad it doesn't really get into some of the more complicated things an advanced H.264 encoder like x264 is doing, e.g. adaptive quantization methods. There's also a mistake or two, for example

> P-frames are frames that will encode a motion vector for each of the macro-blocks from the previous frame.

Actually, P-frames can use data from multiple previous frames, not just the last one.

I think it's worth pointing out, as well, that even though we've technically surpassed H.264 with newer codecs like H.265, VP9, and AV1, all of which are roughly 20%-50% more efficient, this has required tremendous increases in encoding complexity. H.264 is special - it seems to occupy a kind of inflection point on the complexity / efficiency curve. It's far more efficient than previous codecs like Xvid, WMV, and so on, but at the same time even a lot of underpowered devices from over a decade ago can easily play it. We're not likely to see tradeoffs that good again in the video codec space.

parent bscphil 7 years ago

Discussion

Live from the official Hacker News API

A modern reader for Hacker News · SvelteKit + Skeleton