Posted almost 6 years ago. Visible to the public.

Howto provide a single page preview for PDF & TXT with carrierwave

Assert rmagick provision …


gem 'rmagick', '2.13.2' # at this moment the latest stable version


require 'carrierwave/processing/rmagick'

… and define a custom processor


class MyUploader < CarrierWave::Uploader::Base include CarrierWave::RMagick def cover manipulate! do |frame, index| frame if # take only the first page of the file end end version :preview do process :cover process :resize_to_fit => [310, 438] process :convert => :jpg def full_filename (for_file = model.source.file) super.chomp(File.extname(super)) + '.jpg' end end ... # the other stuff end


  • Only PDF and TXT files (and of course images) are previewable to my knowledge till dato.
  • Don't forget to provide rmagick on your server
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Owner of this card:

Martin Straub
Last edit:
over 4 years ago
by Thomas Klemm
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Posted by Martin Straub to makandra dev
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