Color profile being stripped when converting from JPEG to WebP even with both noprofile and stripmeta are false

[arthow4n]

Steps to Reproduce:

1. docker run -it -p 9000:9000 h2non/imaginary -enable-url-source (the image version is h2non/imaginary:1.0.15)
2. Compare the result of http://127.0.0.1:9000/convert?url=https://webkit.org/blog-files/color-gamut/Italy-P3.jpg&type=png and http://127.0.0.1:9000/convert?url=https://webkit.org/blog-files/color-gamut/Italy-P3.jpg&type=webp.
   • Also see other example images in https://webkit.org/blog-files/color-gamut/

Expected Result

The converted WebP image should keep color profile with it unless given stripmeta=true or noprofile=true.

Actual Result

The converted WebP image loses saturation due to lost of embedded color profile.

Solution

I tried to go build locally on my Mac (brew insatlled with newer dependencies) and didn't ran into the issue above. After some investigation, I came into the conclusion that there's something wrong in older versions of libvips, libjpeg-turbo or libwebp that comes with the ubuntu:16.04's apt repository. So I tried to build a image myself with newer dependencies injected. https://github.com/arthow4n/sharp-libvips/blob/v8.6.3/build/lin.sh#L18 (forked from lovell/sharp-libvips as it only have v8.6.1 built, I'm not pretty sure whether the problem will happen with v8.6.1 or not) https://github.com/arthow4n/imaginary/blob/bundle-libvips-v8.6.3/Dockerfile#L71 The result image for the purpose of demonstration is arthow4n/imaginary:included-libvips-8.6.3-upstream-e558c55 which can be pulled from Dockerhub. The problem happens no more by replacing the image used in Steps to Reproduce with it.

I suggest injecting newer dependencies into the image instead of using older ones that come with the distribution repository.