actiontextで画像が表示されない

Question

環境

ruby2.7
rails 6.0.2.1
windows 10 pro

actiontextを久々に実装しようとしたら、画像の表示がアイコンになってしまいます。表示はとくにおかしい部分はなく他の機能もおそらくすべて正常だと思います。なにか原因がわかる方はコメント・回答お願いします。

source 'https://rubygems.org'
git_source(:github) { |repo| "https://github.com/#{repo}.git" }

ruby '2.7.0'

gem 'rails', '~> 6.0.2', '>= 6.0.2.1'
gem 'sqlite3', '~> 1.4'
gem 'puma', '~> 4.1'
gem 'sass-rails', '>= 6'
gem 'webpacker', '~> 4.0'
gem 'turbolinks', '~> 5'
gem 'jbuilder', '~> 2.7'
gem 'nokogiri', '~> 1.11.0.rc1'
gem 'image_processing', '~> 1.9.3'

gem 'bootsnap', '>= 1.4.2', require: false

group :development, :test do
  gem 'byebug', platforms: [:mri, :mingw, :x64_mingw]
end

group :development do
  gem 'web-console', '>= 3.3.0'
end

group :test do
  gem 'capybara', '>= 2.15'
  gem 'selenium-webdriver'
  gem 'webdrivers'
  gem 'rspec-rails'
  gem 'factory_bot_rails'
end

gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]

gem 'devise'
gem 'jquery-rails'
gem 'bootstrap-sass'
gem 'payjp'
gem 'carrierwave'
gem 'kaminari'
gem 'rails_admin', '~> 2.0.0.beta'
gem 'rails-i18n'
gem 'cancancan'
gem 'simple_calendar'
gem "gosu"
gem 'activeadmin'
gem "chartkick"
gem 'devise-i18n'
gem 'devise-i18n-views'

Started GET "/rails/active_storage/representations/eyJfcmFpbHMiOnsibWVzc2FnZSI6IkJBaHBEUT09IiwiZXhwIjpudWxsLCJwdXIiOiJibG9iX2lkIn19--18facbc5e3ba427be6ef7024a203968f2453a254/eyJfcmFpbHMiOnsibWVzc2FnZSI6IkJBaDdCam9VY21WemFYcGxYM1J2WDJ4cGJXbDBXd2RwQWdBRWFRSUFBdz09IiwiZXhwIjpudWxsLCJwdXIiOiJ2YXJpYXRpb24ifX0=--0d865a7a2e7f39224153ed38ea39145634a6aadf/automatic-slideshow-image1.jpg" for ::1 at 2020-02-25 18:30:01 +0900
Processing by ActiveStorage::RepresentationsController#show as JPEG
  Parameters: {"signed_blob_id"=>"eyJfcmFpbHMiOnsibWVzc2FnZSI6IkJBaHBEUT09IiwiZXhwIjpudWxsLCJwdXIiOiJibG9iX2lkIn19--18facbc5e3ba427be6ef7024a203968f2453a254", "variation_key"=>"eyJfcmFpbHMiOnsibWVzc2FnZSI6IkJBaDdCam9VY21WemFYcGxYM1J2WDJ4cGJXbDBXd2RwQWdBRWFRSUFBdz09IiwiZXhwIjpudWxsLCJwdXIiOiJ2YXJpYXRpb24ifX0=--0d865a7a2e7f39224153ed38ea39145634a6aadf", "filename"=>"automatic-slideshow-image1"}
  ActiveStorage::Blob Load (1.1ms)  SELECT "active_storage_blobs".* FROM "active_storage_blobs" WHERE "active_storage_blobs"."id" = ? LIMIT ?  [["id", 8], ["LIMIT", 1]]
  Disk Storage (0.8ms) Checked if file exists at key: variants/u0le8hvylh5ehbw25za2y5vmqefe/a11a36388e78e14e87b3df5ca13fbc2b29985c99a8960faaef7ad20f15b1ae6c (no)
  Disk Storage (18.7ms) Downloaded file from key: u0le8hvylh5ehbw25za2y5vmqefe
Completed 500 Internal Server Error in 2477ms (ActiveRecord: 1.1ms | Allocations: 7713)


  
MiniMagick::Error (You must have ImageMagick or GraphicsMagick installed):

mini_magick (4.10.1) lib/mini_magick/configuration.rb:147:in `cli'
mini_magick (4.10.1) lib/mini_magick.rb:38:in `imagemagick7?'
mini_magick (4.10.1) lib/mini_magick/tool.rb:133:in `executable'
mini_magick (4.10.1) lib/mini_magick/tool.rb:108:in `command'
mini_magick (4.10.1) lib/mini_magick/tool.rb:90:in `call'
image_processing (1.10.3) lib/image_processing/mini_magick.rb:56:in `save_image'
image_processing (1.10.3) lib/image_processing/processor.rb:23:in `call'
image_processing (1.10.3) lib/image_processing/pipeline.rb:50:in `call_processor'
image_processing (1.10.3) lib/image_processing/pipeline.rb:28:in `block in call'
image_processing (1.10.3) lib/image_processing/pipeline.rb:64:in `create_tempfile'
image_processing (1.10.3) lib/image_processing/pipeline.rb:27:in `call'
image_processing (1.10.3) lib/image_processing/builder.rb:13:in `call!'
image_processing (1.10.3) lib/image_processing/chainable.rb:65:in `call'
activestorage (6.0.2.1) lib/active_storage/transformers/image_processing_transformer.rb:15:in `process'

Answer 1

こちらのエラーメッセージにありますが、 この Gem を使用する場合は、予め ImageMagick か GraphicsMagick のインストールが必要です。（インストールされていますか...？）

MiniMagick::Error (You must have ImageMagick or GraphicsMagick installed):

MiniMagic の README にありますが、MiniMagic はこれらのツールの Wrapper です。
https://github.com/minimagick/minimagick#minimagick