WinRAR and 7-Zip Questions....

[eipeks]

So, I have a folder with photos 90.2 MB in size.
Compressing with

WinRAR = 89.9MB
7-Zip = 89.7MB


Now, I hate to sound noobish here, but 1 MB smaller than the original folder doesn't sound like compression to me. Why does it not shrink it smaller?

If I RAR a 1.99 MB Audio mp3 file, the compressed file size is 0.99 MB but if I 7-Zip the same audio file, it ends up being 1.45 MB in .7z format.

I've noticed some files, like a .psd file, will compress nearly 50% of it's original size with both programs however a standard .jpg file hardly compresses at all!

Why?

 

[KSoD]

JPEG and JPG are already compressed files.

It also depends on your compression rate. If you use the default that is only like 10% of what it already is.

You will have to add to Archive and select a different compression rate other than normal to get it to be less than a few MB in size.

 

[carnageX]

It also depends on the file. Some files, like JPEG's in Mak's example, are already compressed and cannot be compressed much or at all anymore.

 

[Jorsoft]

Indeed. In general, though, Winrar has always given me better results over all. I've used it for a long time, too, and find it easier to use than 7-zip or Winzip. But that may be because I know my way around it better.

 

[eipeks]

alright!
Thanks for the input, it all makes much more sense now. And of course, I forgot jpg was already compressed!

 

[KSoD]

Yes many people forget that part. But it is always good for a reminder once in a while.