By using this WordPress plugin you can add a png image as a watermark for all your product images in your Jigoshop store. Advantages of adding a watermark in your product images is that, it will prevent the images from being copied. Also, it will display your brand logo in the images. This plugin can be used for adding watermark in the main product images, for adding watermark in the thumbnails and for adding watermark in the pop-up images.
To add the watermark, all you need to do is to install and activate the plugin. Then, you have to create a transparent png image which would be your logo and would be used as a watermark in all the product images. You can easily create a transparent png image by using Photoshop or GIMP. Here’s a tutorial on how to create transparent images in GIMP. After you have created the transparent watermark image, you can upload it from the plugin settings page and select the position of the watermark. You can add the watermark in 9 positions in the images. You can also select different positions for watermark for main watermark position, pop-up watermark position and thumbnail watermark position.
In future, if you want to change the watermark for the old images, you can do so by using the Regenerate Thumbnails WordPress plugin.