test.jpg
will be stored as test_resized.jpg
th23-upload
folder to your wp-content/plugins
directory.
The plugin is configured via its settings page in the admin area. Find all options under Settings
-> th23 Upload
. The options come with a description of the setting and its behavior directly next to the respective settings field.By default WordPress limits the upload of images to max 2560 px width / height, without providing any admin options to adjust this setting. This plugin allows you to disable this default and replace it with a setting accessible via the admin options.
This plugin additionally allows a customized suffix for resized images, compared to the unchangeable default -scaled
suffix.
Also the plugin can prevent creation of additional intermediate sizes of all uploaded images, which due to their dimensions of 1536px and 2048px would be taking up much additional space on your webserver.
You should use a PNG
image as watermark with transparent background. Try it out locally over various backgrounds/ images - light ones as well as darker ones.
The size depends largely on the size of your images to be marked. You can save a larger copy of the watermark PNG and limit the maximum space to cover via the plugin options. Make sure your watermark is still readable/ visible also when scaled down.
Simple answer: Most images used in the internet are in the JPG
format. Watermarking such images should meet most users needs.
Technical answer: Other image formats can contain information and have special characteristics making their handling very tricky and error-prone. For example: PNG
files can contain transparency levels, additionally they can be animated. Similar for GIF
images.
Honest answer: To limit complexity of the plugin ;-)