Middleman Simple Thumbnailer is a Middleman extension that allows you to create image thumbnails by providing resize_to option to image_tag helper.
Put this line into your Gemfile:
gem 'middleman-simple-thumbnailer'
Enable the extension in config.rb:
activate :middleman_simple_thumbnailer
And modify your image_tag's by adding resize_to parameter:
= image_tag image, resize_to: '50x50', class: 'thumbnail'
You can also use the image_path helper the same way in place where you need only the path of the resized image:
<picture>
<source srcset="<%= image_path "original.jpg", resize_to: 1200 %>" media="(min-width: 900px)">
<%= image_tag "original.jpg", resize_to: "400%", class: 'the-image-class' %>
</picture>
This extension use ImageMagick (via mini_magick) to resize the images.
The resize_to format is therefore the one defined ny ImageMagick. The documentation can be found there.
During development thumbnails will be created on fly and presented as a base64 strings. During build thumbnails will be created as normal files and stored in same dir as their originals.
MIT