Video_2021-.7z -

: It is most effective when you have many similar files (e.g., several versions of the same video or multiple clips from the same shoot). Pros & Cons for Video Archives

if you need quick access to individual videos without waiting for the whole set to process. Does 7z compress better than zip? - Microsoft Community Hub

: Because video files (MP4, MKV) are already highly compressed, you may see limited size reduction unless there are many redundant or identical files in the archive. video_2021-.7z

The in a .7z archive (like your video_2021-.7z ) is a compression method that treats multiple files as a single, continuous data block rather than individual items.

: All uncompressed files are concatenated and processed together. This allows the algorithm to find similarities across different files. : It is most effective when you have many similar files (e

: If any part of a solid block becomes corrupted, it can potentially damage or prevent the extraction of all files within that same block. When to Use it

if you want the absolute smallest file size for long-term storage and plan to extract the entire archive at once. - Microsoft Community Hub : Because video files

While it can significantly improve compression ratios, it has specific trade-offs for video files: How it Works