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When we create a new one, a curator typically provides the developer with a thumbnail cropped from an original TIFF chosen from the digital collections.
(Actual collections are different than these synthetic “featured topics”, and have thumbnaisl that can be edited through the standard web admin interface, which show up in search results, collection show pages, the collections page, etc. This page is only about Featured Topics)
Instructions for the curator
To create the thumbnail:
Download a high-resolution original TIFF from the digital collections.
Crop the TIFF so that the resulting file is a square at least 700x700 pixels on each side. (Bigger is fine)
Assume the bottom sixth of the image will be hidden by the label displayed in front of the thumbnail.
UPDATE WARNING: with the summer 2023 redesign, we possibly need a BIGGER thumbnail than 700, we haven’t yet figured out how to deal with this. It can be shown on the screen currently as big as… 514px (with some cropping on top and bottom), so if we really want 2x, do we need 1028px? Not sure. 700 might be enough, just without 2x resolution.
Place the cropped TIFF (as a TIFF, so it can still be resized losslessly) in:
P:\Othmer Library\Digital Collections - External Access\Crops for Hydra Redesign\cropped_tiffs\categories
Instructions for the developer
Use the following imagemagick command to convert the thumbnail to a jpg:convert original_file.tif -density 600x600 -resize 700x new_thumbnail_2x.jpg
Warning see note above about summer 2023 redesign, we’re not sure what size we need, might be bigger than 700….
The resulting thumbnail checked into the codebase should be:
a jpg
600x600 density (we aren’t totally sure why this matters, but think it’s what we’ve been doing)
progressive JPG (displays better while in process of being loaded by browser)
700 pixels wide x 700 pixels tall (we have a 350pixel spot on the page, and want double density to look good on high-res displays)
with a name ending in
_2x.jpg, consistent with the other files in the featured topics asset directory.
See also
For more technical information on featured topics, see: app/controllers/featured_topic_controller.rb and app/views/homepage/_featured_topics.html.erb .
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