Apple TV Movie File Sizes

I recently downloaded a new movie release from Apple TV and noticed the file size seemed somewhat small and made me think the whole file didn’t download … went to check and nope, the whole movie downloaded.
This particular film was 2hrs44m with a file size of a mere 2.8 G. I have any number of comparable length movies and even shorter length films with larger or much larger file sizes …
All of these are 1080p … is there some sort of new 1080p protocol?
Or are the other films just that much more colorful or something?

My first guess would be that the movies in question are saved in the H.265 format, also known as HEVC, or High Efficiency Video Coding. HEVC does in fact create video files which are much smaller than H.264 compression and other video codecs. Despite the much smaller size, you will notice that there is NO quality loss. It is quite mind-blowing. If you are not familiar with HEVC you can learn more about it here:

In fact, I seem to recall having recently read that there is something even better than HEVC called AV1. You can read about it here:

I hope the above helps.