The claim by the vendor of

“Lossless Quality: Maintain the original resolution and format of your photos after processing.”

point one it cannot be lossless as it’s supposedly removed the watermark so some data has been changed.

If the source image and resultant saved processed image uses a lossy compression like JPEG or WEBP or HEIC then no matter what you do each generation of recompression WILL introduce losses of information.

plus this uses an old pirated copy of GPLv3 FFMPEG DLLs to do the handling of image compression and basic watermark removal which is VERY ugly. It is also Adware with Buttons for OTHER paid for products placed on the screen for “DRM Protection”, “Multimedia Toolkit” and “All-in-One Toolkit” The so called AI Repair is nothing of the sort this is a 32bit program no current AI model fits in 32bit windows! AI Repair pretends to do something with a quick progress bar window but makes no apparent changes to the image under 64bit Windows 10 and under 32bit Windows Vista does what commentor “g2k1” noticed.

All the FFMPEG derived methods are ugly and certainly not lossless and are obvious something has been mutilated under both systems. In my honest opinion for watermark removal this is a waste of space. It also has stupid bugs e.g. because its a 32bit application one can crash it using the Zoom control in the “Filter” section at least and zooming a 3200×1912 pixel image by 752% resulted in an error box popup warning “Not enough memory resource to process this command” The system has 16G of RAM there is plenty on the system but not in 32bit user-space the program is built in… lets see if the program recovers from the untrapped error, nope instead of rendering anything it present a blank white canvas this needs alpha testing zoom should not be allowed to consume more memory than can be allocated to the program! Oddly watching this in task manager it runs out of memory at 1035.1 MB allocated. and there is a memory leak in that it continues to keep most of the memory allocated after dismissing the error, and even after closing the image and having no image loaded. yup this needs alpha and beta testing!

I note that the filters are downloaded as PNG files from their server only when you try to use them… they should be part of the installation not served from a server when you need them… It means initially you have to use this online to get the filters! And when any filter is enabled the memory allocation bug on zooming moderately sized images occurs.
At worst ther should be an option to download ALL the filters at one time and not download on clicking only as that will take ages if one just wants to preview the filters effects! Filters are downloaded to
C:\Users\[USERNAME]\AppData\Roaming\ThunderSoft\Watermark Remover\Filter\

no matter where you choose to install this because they obviously must have write access to save the downloaded PNG files into it so be aware if your system drive is a small SSD.