After seeing many posts and several servers using upscaled textures I decided to start looking into ways of doing and automating it.
We will need two different tools for this
Upscayl (free AI image upscaler)
Irfanview (image tool that allows bulk conversion between formats)
Before starting with the guide itself, a few notes:
Upscayl doesn't allow using BMP images, so every texture we want to change will need to follow the following process:
Convert BMP to JPEG -> Upscale in Upscayl -> Convert JPEG to BMP
The results are by no means perfect, and some of the texture might not look perfect in game, specially when two textures go together, but it's a good starting point.
Now for the guide itself:
1 - Extract textures from GRF
I will not explain how to do this. You can use a tool like GRF editor to extract the textures from the official GRF's.
2 - Bulk convert BMP to JPEG with Irfanview
In Irfanview load the folder containing the BMP files and click on Add All. Select the output as JPEG, choose the output folder and click Start Batch when ready.
3 - Upscale images with Upscayl
Select Batch Upscayl and select the folder with the JPEG files generated in the previous step.
Select which model we want to use. At the time of writing there are 6 different models, so I recommend to start playing around with it with a single image to see the results before doing a bath upscale.
Select the scale. This is very important. RO textures are usually 256x256. Upscayl supports up to 16x! (4096x4096). The more resolution the best results, however, not only will this take longer to generate images, they will also weight way too much. I recommend leaving it as 2x
Select the output folder.
Upscayl! This can take a while depending on your PC, the settings you have chosen and the number of textures. At the end of the process you should have all the new upscaled JPEG textures in the folder you selected.
Below is an example of an upscaled texture using the digital art model (this is a screenshot taken directly from the program, once converted it won't have the watermark)
Below is an example of an upscaled texture using the ultramix balanced model (this is a screenshot taken directly from the program, once converted it won't have the watermark)
4 - Bulk convert JPEG to BMP with Irfanview
In Irfanview load the folder containing the JPEG files and click on Add All. Select the output as BMP, choose the output folder and click Start Batch when ready.
5 - Put new texture in your data folder or GRF
Put the newly generated BMP images in your data folder or GRF, start your server and give it a try!