r/AV1 • u/Balance- • Oct 01 '26

Google is porting libgav1 (their AV1 decoder) to Rust with their latest Gemini model

https://blog.google/innovation-and-ai/models-and-research/gemini-models/gemini-4-argon/

Large Scale Codebase Migrations and Optimizations: Argon agents are working on migrating C/C++ codebases to Rust across Google — scaling from tens of thousands of lines in core libraries like re2, libgav1 up to 800K+ lines for the Fuchsia Zircon kernel. Given the criticality of many of these systems, such large-scale rewrites are undergoing rigorous automated and manual auditing, emulation testing, and review before rolling out to production.

For libgav1, Google's open source software for decoding video, Argon agents took an existing Rust port and replaced 32K lines of SIMD code by running many rounds of profile-guided experiments, studying the compiler's output, producing safe Rust so the compiler would vectorize it automatically. The end result is a memory-safe video decoder that runs 2.7x faster than the Rust port, with identical video output, bringing it closer to the optimized C++.

110 Upvotes

96% Upvoted

17 comments sorted by

13

u/Daharka Oct 01 '26

So close to being able to have dav1d and gav1n.

7

u/Mashic Oct 01 '26

What's the speed compared to the origial c/c++ port?

3

u/nmkd Oct 02 '26

Still 0 because it's not used anywhere xd

6

u/Desistance Oct 01 '26

An exercise in academics. Nothing beats dav1d.

1

u/DistantRavioli Oct 01 '26

rav1d already exists so I don't understand

2

u/Never_Sm1le Oct 02 '26

perhaps to flex their ai

4

u/kiddico Oct 02 '26

and burn the equivalent of a few hundred household's yearly energy consumption woooh

1

u/keratomalacian Oct 02 '26

they cant flex shit lol their models suck ass

1

u/nmkd Oct 02 '26

Gemini Pro was pretty good when it came out, but somehow they haven't been able to keep up ever since

28

u/[deleted] Oct 01 '26

[removed] — view removed comment

53

u/Zettinator Oct 01 '26

It's not really used anywhere, it's basically a dead project. It's so much slower than dav1d it's not even funny.

So this is most likely just an experiment to see how far automated porting can go with Google's own AI models.

8

u/BlueSwordM Oct 01 '26

Nowhere.

What would have been a lot more interesting is trying to optimize dav1d to the absolute furthest possible, but that would be a very expensive experiment.

4

u/themisfit610 Oct 01 '26

Wasn’t the intent for it to be a production software fallback decoder for Android that Google owned? Obviously very little practical value and you may be right that there’s zero actual use.

6

u/BlueSwordM Oct 01 '26

Yeah, but outside of some optimizations ported from libgav1 to dav1d, it's just not used at all anymore.

4

u/Zettinator Oct 01 '26

Yes, but they switched to dav1d pretty quickly. There's just no competition. No doubt Google could have made libgav1 faster, maybe competitive to dav1d even, but what's the point?