Means of Regenerating PDF Thumbnails in your WordPress
Recently a user asked if generating PDF thumbnails for use in WordPress was possible. WordPress 4.7 or higher, features thumbnail previews of all new PDF files. However, the change has no impact on older uploads. Here are the means of generating PDF thumbnails in your WordPress for uploads that are older.
Reasons to Regenerate PDF Thumbnails
PDF thumbnail previews were first introduced by in WordPress 4.7. This feature works by creating image previews. The previews are of the initial page of any PDF file you upload via the media upload. But, the effects of the features apply only to new PDF files. Also, these are PDF files that you upload after upgrading your site to WordPress 4.7 or higher.
To display a thumbnail preview of attachment pages, you must apply the PDF plugin. Hence, the appearance of all PDF files that are old will be a general symbol in your WordPress media library.
Do you upload PDF files regularly on your WordPress site? If yes, then you must regenerate thumbnails of older PDF uploads. Thumbnail regeneration of older PDF uploads resembles regenerating thumbnails of your images. Nonetheless, the plugins are currently not supporting PDF files. Here are the means on how to regenerate PDF thumbnails of older uploads in your WordPress.
How to Regenerate WordPress PDF Thumbnails
Ensure you have upgraded your WordPress to WordPress 4.8 before you start the process. Besides, you ensure that you have installed ImageMagick extension on the server you are using.
Now, upload a PDF file on your WordPress site to test your ImageMagick. Proceed with the process when the extension displays a thumbnail preview of the PDF file.
However, the plugin we will use in our case can generate thumbnails of both older files and images. Also, it is recommendable you create a backup. It should be of content, folder or your WordPress site. Besides, this should be before you start regenerating thumbnails.
To start the process, install the Force Regeneration Thumbnails plugin. Additionally, ensure you have activated it. GitHub hosts the plugin. Thus, it is important you check the guide on the installation of plugins obtained from GitHub. It is recommendable if you have never installed plugins from the site before.
Once activated, move to tools and open the Force Regenerate Thumbnails page. As a result, you will be able to regenerate thumbnails of all PDF files and images. But, these are files and images you have ever uploaded on WordPress site using the media upload.
To start the regeneration of the thumbnails, click the "Regenerate All Thumbnails" button. Processing will start. Based on the number of PDF files and images, the processing time of images on your site by the plugin will vary.
After processing PDF files and images on your site, move to media and open the library. Here, you will see all thumbnails previews of the old PDF upload. The plugin regenerates all thumbnails at once. Besides, it enables you to regenerate thumbnails from specific files. Regenerating individual thumbnails is suitable if the PDF files are fewer. However, to regenerate individual files, move to the media bar. Open the library page, and then click the list view for display. Now move your mouse over a PDF file, and a ‘Force regenerate thumbnails’ link will appear. To regenerate thumbnails of the file, click the link.
You are done with regenerating thumbnails of all old PDF uploads. You are safe to delete or deactivate the plugin. Reason: thumbnails regenerated will not get removed.