Total file size in SharePoint vs Version size

Hello,

I was looking for answers regarding my findings. I analyzed our SPO tenant because we are running out of storage. During the analysis, I discovered that our video files show different sizes in '/_layouts/15/storman.aspx' under the Total Size column compared to when I open specific versions of the files. In SharePoint, the Total Size column is almost double the size of the version size. How is that possible? I searched for an explanation but couldn't find one. Based on discussions, it seems that different resolutions and thumbnails are stored in a hidden folder. Is that correct? Is it possible to locate these hidden folders?

Thank you

Mirek