Consider using zune-jpeg in place of turbojpeg

[Shnatsel]

zune-jpeg is an extremely fast JPEG decoder written in safe Rust. It is generally on par with libjpeg-turbo in terms of performance (some files are slightly faster, some slightly slower). You can find the benchmarks here.

It would be great to use the memory-safe decoder now that a performant option is available.

For reference, a PR integrating it with image can be found here: image-rs/image#1877
It is expected to be landed in the next API break, replacing the jpeg-decoder crate, but it's not clear when that is going to happen.

[woelper]

Thank you!

I think this is fantastic - I believe I looked at this option before and the only thing that held me back is that I am using turbojpeg for lossless transformations as well. As long as we want to support these, turbojpeg needs to stay. Although zune-jpeg could be used for decoding, this would probably not get rid of turbojpeg itself - but I guess memory safety would be worth it.

[woelper]

Hey! Zune-jpeg is now the default in the image library. As such, oculante will use it if you disable the turbo flag, so you can easily build a version without turbojpeg. I will leave turbojpeg as default until there is a way to do lossless transformations with zune-jpeg.