bug: needlessly modifying images' ICC profiles

[gianni-rosato]

What happened?

Sending images via Revolt appears to strip ICC color profile information, which causes some images to display incorrectly. Upon sending an image like this to Revolt, the color information is stripped from the image & it ends up looking wrong. Discord only strips the ICC color information in previews, when pressing "view full image" it is actually intact. Additionally, most modern browsers support ICC color management.

I understand stripping metadata to preserve user privacy, but it is never harmful to keep the ICC color profile around to make sure the image's color information is displayed properly. Additionally, every iPhone takes images tagged with the P3 color profile. ICC color information can be preserved with exiftool by running exiftool -all= --icc_profile:all input.jpg.

[insertish]

Would like to do this Rust native and not pull in exiftool (appears to be quite difficult to get a static copy).
One option is little_exif, but ran into an issue that needs investigating, relevant issue: TechnikTobi/little_exif#12

[insertish]

Tried to rebase forked crate on main, now does not build due to:

error[E0658]: use of unstable library feature 'seek_seek_relative'
   --> /home/izzy/.cargo/registry/src/index.crates.io-6f17d22bba15001f/revolt_little_exif-0.5.1/src/png/vec.rs:174:11
    |
174 |             cursor.seek_relative(chunk.length() as i64 + 12)?;
    |                    ^^^^^^^^^^^^^
    |
    = note: see issue #117374 <https://github.com/rust-lang/rust/issues/117374> for more information

Blocked on #341

[TechnikTobi]

I see. Is this the only unstable feature used by little_exif? If so I can look into a work around that would be part of the 0.6.0 release (which, as far as I can tell, is able to properly read in the EXIF information from your example file).

Edit: Checked this, replacing seek_relative is viable and the only change required for 1.77.2 compatibility. Will be available in the 0.6.0 release.