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Serve image thumbnails instead of full-size until expanded

Currently, every post containing images on Cohost features the full-sized image, used for both the scaled-down preview (dimensions: 260x197 on my computer) and the scaled-up version in the lightbox.


This means that, in the extreme case, I could embed four ten-megabyte images, and someone scrolling past my post would have to load forty megabytes of data. I use Google Fi and it would cost me forty cents just to scroll past that post on the bus. This presents similar issues for people in developing countries who may have slower, less reliable, or similarly expensive Internet connections.


As a photographer I am pleased that Cohost doesn't recompress my images for full-size display, but other than perceptually instant full-size images (since they're preloaded), I don't see any benefits for users of using the entire full-size image as the thumbnail. Serving thumbnails until an image is expanded would presumably also save a tremendous amount of bandwidth on Cohost's side.


A pixel artist might have an edge case here, but this could be handled with an on-by-default checkbox, or clearly-documented heuristics on what to always serve full-size (pixel dimensions, format, filesize, etc).


18 people like this idea

The only thing to look out for (that I can think of) would be cases where thumbnail generation runs into issues with animated GIFs or PNGs with transparency, but I'd like to hope this is a non-issue nowadays

1 person likes this

like with the other exif stripping feature request, another thing to look out for again is color profile information (maybe image rotation too…?). A lot of applications that generate thumbnails (e.g. slack, discordapp, etc.) will discard this data, so you get pictures that look very different in thumbnail form and when expanded. (this is a pet peeve of mine. discordapp in particular never even shows you an un-thumbnailed version in the desktop app, so everyone except mobile users will see distorted colors unless you manually convert to srgb before uploading. but if you do that then you lose all the extra color gamut…)

(though, like, generally, given cohost’s support for more unusual image formats like heif and avif, which support hdr color, this may actually be kinda difficult…)


2 people like this

Yes please! I'm on a prepaid plan and cohost eats up so much data. 


2 people like this

Really need this. The site now has more users, it takes forever to load up a page with dozen of images.

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