Ubuntu and .pdf

The main principle of the alternative is that sometimes it works sometimes it doesn't work.
When it made about a software (no, sorry, it's not a reason to consider Windows as alternative) it's a real problem...

For example I'va made my book in .pdf and it's a 14MB assembled document, so I've to compress it to email it. I've tried softwares on my Ubuntu but no one allowed a good compression (if you have an idea, comments are open). One of them created a 235MB file...

Well, I asked a friend to help me, I do thank him as the Acrobat compression took him half an hour... Yes, that's a lot, I know, but here is what I saw when he sent me the file:

You're not dreaming: without picture the page is clear but when there are photos it's unreadable (texts and vectors).
Except that the file is well-displayed with Windows and Mac... If an Ubuntu-expert read this, please, help me to cook good .pdf!

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