I want to know how to protect texture data

[race-department-tayou]

I would like to make a course and publish it on the internet.
I sometimes analyze official and public courses for study purposes.
I knew at that time. I noticed that the extracted texture data is strange.
The data capacity is 70 bytes.
The image size is also only 1x1px.

I'm guessing this is due to protection.
It's a very attractive protect. But I don't know how to protect this.
How can I protect it?
Is it protected when output with modeling software? Or is it protected when output with kseditor? How do you do that again?

I have prepared a screenshot of the texture in question in the attachment. Thumbnails are also 1x1px.