I don't care how long it takes to compress, all I want to achieve is two things:
- The absolute best possible compression ratio
- Compatibility with standard readers, such as Windows and WinZip
So suggestions such as 7-zip won't be of much use, unless 7-zip is also slightly better at the standard ZIP compression (as opposed to using it's very good .7z format).
Ideally I'm looking for:
- A recommendation of a piece of software
- The particular settings for that software that enable the absolute best compression
- Something that's free
Remember, how long it takes to compress is not an issue!
One last thing – some files might be better compressed with different settings, like the "Word size" or "Dictionary size" – is there a tool that can analyse the files and choose the most appropriate compression ratio, or does WinZip, 7-zip etc. already do that?