Hello:

I'm experimenting with zip files. Example: Using 7-Zip, I selected 15MB worth of pics and put them in a .zip FILE using the "Ultra" compression level. I started with 15MB and ended with 15MB. I emailed them to myself and it TOOK as long to send as if I attached the photos separately. Therefore, I don't see the benefit. Can you please explain?Zip files, and other compressed formats, are only really good at compressing non-compressed files. Pictures are USUALLY already compressed (like the most common .jpg FORMAT is) and so zipping them doesn't reduce the file size appreciably. Try that again with, say, text files, and you'd most likely see a huge difference.
Hope this helps.Thanks, that makes sense,You're welcome, glad I could help.You might want to read this, although it might be more than you want to know.

http://en.wikipedia.org/wiki/ZIP_%28file_format%29

Zip files were originally mainly created to compress spreadsheets, and they made a huge reduction in the size of most spreadsheets since they have so much unused space.


Quote from: Calum on April 17, 2010, 08:56:43 AM

Zip files, and other compressed formats, are only really good at compressing non-compressed files. Pictures are usually already compressed (like the most common .jpg format is) and so zipping them doesn't reduce the file size appreciably. Try that again with, say, text files, and you'd most likely see a huge difference.
Hope this helps.