unable to reduce file size for a PDF in Acrobat Pro

[pierret18811376]

Hello,

I have Acrobat Pro version 23.001.20143.

I have a PDF made of 68 pages and 30,5 Mo.

In Acrobat Pro, If I go to File / Reduce file size, it says me that : "the file size of this PDF is already minimized. No further reduction is possible".

So I am unable to reduce file size. Have you a solution ?

[Bernd Alheit]

In Acrobat Pro try the PDF Optimizer.

[Test Screen Name]

It is probably right. Just because you want a smaller file, it is not always possible. It is easy to prove not every file can be made smaller. 

[pierret18811376]

That is strange is for this PDF file made of 68 pages (image and text), I cannot reduce file size (always around 30 Mo).

But I have another PDF files of 40 pages that have a file size going from 1,38 Mo to 7,70 Mo (files with image and text, like my PDF of 68 pages).

So I am wondering if for my PDF of 68 pages, the problem is it coming from this specific PDF file or from Acrobat Pro ?

[Test Screen Name]

This seems normal. Every PDF is different. You cannot set a target size per page. Some have more pictures, more fonts, more drawings... sometimes a pretty background picture over the page will make the size x10. All this is normal, you must not just expect to be able to "fix" this to some target size without a redesign.

In PDF optimizer you can use Audit Space Usage to look at what is using all the space. Perhaps redesigning the pages is a solution.

[pierret18811376]

@Test Screen Name 

You have said : "In PDF optimizer you can use Audit Space Usage to look at what is using all the space.".

I gone in PDF optimizer and clicked on the button "Audit Space usage", and here are the results :

It seems that my problem is coming from "Content stream" (78%), but I don't know what is "content stream".

[Bernd Alheit]

Have you line graphics in the document?

[pierret18811376]

@Bernd Alheit 

When you are talking about "Line graphics", I suppose it is corresponding to lines surrounding text frames ?

This PDF is a magazine with text, photos and lines surrounding text frames.

[Bernd Alheit]

I mean graphics build with lines. 

[pierret18811376]

@Bernd Alheit 

There is no graphics build with lines in this PDF.

[Rando_corpo_guy]

How are the images saved? If you can find a way to ruduce the image sizes that might help some. Mybe if they are CMYK but could also be RGB, the RGB tends to be smaller. 

Another thing to try is to run a preflight clena up prior to optomizing the PDF. In the Optomize Tool, look for Preflight menu. Open the PDF Fixups list, then run (double-click) both Flatten fixups. These alone won't reduce siz much but once you optomize after this step you should see some file size reduction with minimal resolution loss (depending on your Optomization settigns really).