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Comment by Nanopolygon | Hacker News Reader

QOI is just a simple filter. It cannot do full compression. In fact, in certain cases it can increase the size instead of compressing. It is unnecessarily overrated, of course, mostly because it is open source. The rest is irrelevant. There is another codec that is as fast as QOI (or even faster and multi-core) but with a much higher compression ratio. HALIC (High Availability Lossless Image Compression). But because it's closed source, it definitely didn't get the attention and respect it should have gotten. And that's why I think it stopped developing.

https://github.com/Hakan-Abbas/HALIC-High-Availability-Lossl...

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>>> In fact, in certain cases it can increase the size instead of compressing.

Fwiw, all (lossless) compression algorithms will increase the size of some inputs.

> Fwiw, all (lossless) compression algorithms will increase the size of some inputs.

They rarely meaningfully increase the size though. Typical compression algorithms, when faced with hard to compress sections, can add a handful of bits to wrap them up. Total overhead a fraction of a percent.

When QOI encounters noisy pixels, it has to spend an extra byte per pixel, inflating the file by 33%.

one pretty simple qoi improvement would be a tag to say to store the next n pixels uncompressed. I think there's room in the tags for adding it

I wanted to use HALIC but ended up using SQZ instead. QOI is overrated but QOIR and my own QOIX are a bit more interesting, albeit ultimately stupid.

A simple filter may still do wonder if it is carefully chosen ;-)

The apparent death of HALIC was indeed unfortunate, I've heard that its decoder was less than 1K lines of code so it must have had a carefully designed and optimized context model in its heart. But there are so many other formats that are F/OSS but weren't highlighted enough anyway...

For a format to proliferate as a standard, it has to be open source. Nobody cares about 5% smaller images if not everyone can view them.

Historically speaking, that’s not true; WMV and FLV were extremely popular for over a decade in the early 2000s. Closed source formats can, and have, become de facto standards if they solve a pressing need that open standards don’t (or provide a stepwise increase in functionality or performance) and if there’s sufficient market demand.

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