How to create thumbnail of different files?

You’re already looking in the right places. (And nowadays WordPress already supports PDF thumbnails through ImageMagick – code.)

To add a new thumbnail generator, you’ll need to:

  • write a new WP_Image_Editor class that supports the file type or types you want – you’ll want to extend the base class and override at least
    • test()
    • load()
    • supports_mime_type() – to match the content types of the files you want to preview
    • multi_resize() – this is the method called to generate thumbnails
  • hook the wp_image_editors filter, and in the hook implementation include your editor class (if you haven’t already) and add the class name to the filtered list, with whatever priority you want.

Related Posts:

  1. Save image as featured image
  2. Add version query tag to all images
  3. Get thumbnails with array sizes parameter
  4. The URL of images on my website changed after being set as featured image
  5. Thumbnails for media Library images
  6. What’s the difference between term_id and term_taxonomy_id
  7. How are bulk actions handled in custom list table classes?
  8. How do I programatically insert a new menu item?
  9. When would I use either function for plugins?
  10. Test to see if jQuery or Prototype is queued by another plugin?
  11. Custom Nav Menu items default to ‘menu-item-type’ => ‘custom’. How to make a “page” menu item?
  12. How to tell if an option has been created vs an empty option?
  13. jQuery in header or footer
  14. Notice: _usort_terms_by_ID is deprecated since version 4.7.0! Use wp_list_sort instead
  15. How to add a new plugin page under desired Options page?
  16. Plugin screenshots not showing in the repository
  17. How to make WordPress use non-greedy shortcode parsing?
  18. Multiple Parameters for a Shortcode
  19. How to get current page name in my wordpress plugin
  20. WP Cron doesn’t save or in post body
  21. Use register_taxonomy() in register_activation_hook()
  22. Pages 404 in wordpress
  23. How to properly load text domain of custom mu plugin
  24. Post from front-end with post types, categories and taxonomies
  25. product-attribute-slug-is-too-long-28-characters-max
  26. Calling apply_filters on non-documented hooks
  27. Multiple entries in get_option results? or why is _multiwidget set to 1?
  28. Check if I am in the Admin Panel (wp-admin)?
  29. Fully automated theme install and activation via a plugin
  30. Using Ajax call in jQuery doesn’t work in widget
  31. Plugin activation error due to unexpected output
  32. How to store data for posts/pages built with drag-n-drop builder?
  33. WP rest api v2 posts filter by ‘search’ & ‘category_name’ not working
  34. WordPress Admin Post Type Table Class Filter Hook
  35. Order of Operation for these three hooks
  36. How to disable “Transform to” option in Gutenberg custom blocks
  37. save_post hook not triggered in WP v3.6.1
  38. How to get the ID of the currently logged in user?
  39. How to create a Tools menu on the Network Admin dashboard from a plugin
  40. Using a Shortcode to Replace Themes Stylesheet?
  41. Where should I put “run once” plugin pages?
  42. Initial help with official “create a block” tutorial
  43. Update/insert only a column of database table
  44. Can wp_list_comments output into variable?
  45. Plugin Development Output
  46. SMS registration and login [closed]
  47. How to modify product page for Jigoshop
  48. Adding Second Plugin Author
  49. Securing/Escaping Output of file content – reading via fread() in PHP
  50. Run code once when block is created
  51. Intermittent database errors when accessing WordPress database
  52. How to create a “View” page for entry in add_menu_page wordpress admin area (CRUD operation)
  53. what is the standard ulr for wordpress plugin development?
  54. Customize WooCommerce my account dashboard through plugin
  55. Precaching WordPress posts with a ServiceWorker
  56. Shortcode returning localized HTML part
  57. Create a custom capability to allow an ‘Editor’ to edit only ‘Subscriber’ users
  58. global $current_user not current user
  59. What is the proper way to get logged in user id in a plugin?
  60. Custom WordPress Plugin will install new and not update
  61. get_option() will not work without access to wp-config.php
  62. register_activation_hook on multisite
  63. Use ‘get’ form action within a WordPress plugin admin page
  64. Template directory in plugin
  65. WordPress Admin Login Custom Logo
  66. Ajax is not working in a loop
  67. Woocommerce order empty items array
  68. Bind a function with its own argument to show something dynamically after every content
  69. Plugin development – loading Javascript and Flash
  70. Drawing the line between theme & plugin on large scale bespoke projects
  71. HowTo to add my rewrite rules at the beginning, redirect to the right page and flush the rules on plugin activation?
  72. Apply styles to blockquote element with the WYSIWYG editor
  73. Update variable value via add_filter
  74. Do I need to create an endpoint?
  75. How to check whether checkbox is checked in WordPress customizer
  76. How to find list of all functions bind to a particular hook from my plugin?
  77. How to output CSS to the beginning of the stylesheet in a WordPress Plugin
  78. Set page to draft on plugin deactivation
  79. Can one plugin activate another plugin via script?
  80. Insert and read media from the WordPress library and call in the plugin
  81. How to create dynamic content with get_post_meta?
  82. Get value of custom checkbox from Gutenberg sidebar in plugin
  83. Enable a role named ‘backend_user’ to access my plugin pages
  84. Hiding class namespace from plugin’s extensions
  85. How to trigger WooCommerce user profile edit change?
  86. Return raw image proxy for wordpress plugin
  87. Stop unauthorised file access
  88. Changed media upload path for plugin, but generates error & shows wrong url
  89. How to pass a more variable with page/subpage in Wordprees URL?
  90. Use a page as a template for a custom post type
  91. Dynamic sidebar areas not working on the Theme Customizer
  92. Woo-commerce: Adding additional page sections using a child theme
  93. Plugin dev: How to multiply instances of a plugin in the same metabox?
  94. Merge Codes using redux framework
  95. How to get html tag ids from template?
  96. Getting Plugin to read all script files
  97. How to Prove Ownership of plugin [closed]
  98. get_term_by() returning null on plugin
  99. Elementor Top-Bar
  100. Is it possible to add Custom Dashboard Widgets to Custom Admin Menu Page?