Easy Watermark turning images black

Hi there!

I’m writing to you as one of the creators behind the plugin “Compress JPEG & PNG images”. We noticed a problem with your plugin that we would like you to be aware of:

I uploaded an image and compressed the different sizes using our plugin. The image that I used was a png with a lot of transparency. The original image was ~30kb and the compressed version was ~28kb (the image was already quite compressed). However, after I added the watermark (with compression set to 100% for Easy Watermark) the image became ~15kb. This seemed very strange so I had a look at the image and it turns out that the image was completely destroyed. 95% of the image had turned completely black.

This leads me to believe that there’s something wrong with the Easy Watermark plugin. This in turn confuses our plugin and things get messy. Do you know what can be done about this?

You can get the image that I tried from here:
https://voormedia.com/blog/2016/12/optimising-jpeg-image-compression-by-identifying-image-characteristics/images/DCT-d28937dd.png