This Plugin deletes unused thumbs and clean library and removes old unused thumbs when you click on regenrate thumbs for new It makes regenerating thumbnails easier and more flexible using ajax, jquery & REST api so no refresh of page why thumbnail regenerate is required.
It's usual for wordpress sites to change the theme as you change the themes, the new thumbnails are required as per that theme configuration. few themes required 5-6 thumbnails while complex themes require more than 20 thumbnails in some cases but as you had uploaded your images earlier when this theme was not installed, your old theme generated thumbnails as per old theme requirement..
Thumbnails generation is server intensive task and if you are in shared hosting, your host may create problem for you. even for dedicated hosting, why do you want to overload your server, when same thing with quality thumbnails can be done in cloud and that too free so regenerate thumbs in cloud now..
This plugin will help to generate thumbnail from all post thumbnail in one click for new theme post thumbnails of all old images are very important so create thumbnail in one click and it will force to recreate thumbnails..
Thumbnail regenerator will delete thumbs which is not required unused thumbnails may fill your disk space so check the option delete unused thumbnails if you dont want obsolete thumbs.
Plugin sends your image to our server to generate the required thumbnails as well as some sort of in present thumbnails images.
Unfortunately the time script is allowed to run is limited, which sets upper limit to the number of thumbnails you can regenerate.
You can also choose to rebuild post thumbnails . plugin to generate Featured Image from first in post or any custom post type content.
Post Thumbnail, now Featured Image, is image that is chosen as the image for Posts.
Auto thumbnail generation for video sharing services YouTube, Vimeo, Blip.tv, Justin.tv, DailyMotion and MetaCafe.
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