Create Thumbnail Image For A PDF

The rmagick gem is a wrapper around the ImageMagick software suite. This gem can be used to create a thumbnail image of a PDF using the following snippet of code.

require 'rmagick'
pdf = Magick::ImageList.new('document.pdf')
first_page = pdf.first
scaled_page = first_page.scale(300, 450)
scaled_page.write('document-thumbnail.jpg')

The scale can be adjust as necessary to the use case.

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