RAR is 3x larger than its content

[MyronGold666]

I've downloaded a couple of RAR files and noticed something very strange:

 

File1.rar: 1.94GB

Video1.TS: 1.92GB

Readme.rtf: 1KB

 

 

File2.rar: 1.94GB

Video2.MP4: 627MB

Readme.rtf: 1KB

File2.rar is supposed to contain Video2.TS, an HD video file, but it mistakenly contains Video2.MP4, a lower resolution version of the same video.

 

The thing that is totally baffling me though is that the compressed .rar file is 1.94GB, the size that it would have been if it contained the HD video, but its contents are only 627MB. There are no hidden files, nothing weird about it (apart from the obvious.)

 

So the question is, how is this even possible?

[jumper]

Rar archives may not always get compacted when individual files are deleted from within them. Same for 7z and other formats.

[Tripredacus]

WIMs operate similarly but you can rebuild them with imagex. Is there a similar tool or method to rebuild RAR or 7ZIP files?