Flatten PDF layers (that aren't layers in the layer list)

Forum|Forum|7 years ago
June 18, 2018
3 replies
6777 views

Hi,

I've been trying this for quite some time, and still haven't found any answers to it.

Basically I produce a PDF map file, which has map windows one over the other (i.e. main window and inset - say showing where the main window is within australia).

With all these layers included, drawing the PDF page is slow (it adds the content layer by layer), adds unnecessary imagery (makes it bigger than it needs), and includes unwanted information making it look sloppy. What I need is to be able to merge so that only the visible layers are still there. Note that there are no layers in the PDF layers panel. But there is layered (or overlapping) imagery in the PDF.

There must be a way to do this, surely? I would attach the map but can't see an attach file option here.

So, I've tried:

- redact - this works (remove overlapping objects), but makes the whole page rasterized, the text not selectable and of crappy quality

- optimise - especially selecting transparency: high resolution (doesn't work), Discard objects: detect and merge image fragments (doesn't work), Discard user data: Discard hidden layer content and flatten visible layers & discard all object data (doesn't work) - all of these improve things, but don't fix the basic issue

- pre-flight - can't find anything here that seems to work

- tried javascript - this.flattenPages() (doesn't work).

Does anyone know of a way to get this to work? Must be quite a common experience.

Cheers

Edit and convert PDFs

T

Test Screen Name

Legend

Never heard of anyone trying to implement this enormously challenging task for PDF. Certainly there is nothing built into Acrobat and it would be impossible with JavaScript.

This drawing one at a time: does it happen with the local file or only in a browser? Which browser(s)?

T

Test Screen Name

Legend

Interestingly, there are at least four popular definitions of the word "flatten" as applied to forms:

* Make form fields part of the document

* Make transparency opaque

* Remove layer labels

* Rasterise pages

It seems you want a fifth!

D

Dave Merchant

Legend

The term 'flatten' is actually exactly what I (and many others) want to do, and quite simple in terms of what's needed. Take the various layers and flatten them so that there aren't hidden layers, cropped images, etc. - one layer remaining, perhaps with vector text over the top but that's fine.

I realise that acrobat doesn't see the objects as layers, but that's what they are in reality.

The way i see it, acrobat can figure out how to display the PDF with all those layers, so I would think there should be a way to rectify it into a more rationale page somehow?

Of course I am hearing everyone saying there is nothing like this. Is there any third party software out there?

Note, in mucking around with the source software I managed to get the below which is what i'm after (see the difference between the two, viewing and by going to 'edit' and deleting objects in both), but I have this same problem with other PDFs and would still like to try to find a solution:

Shared Files - Acrobat.com

Cheers

PDF files are collections of 'page objects', which each have to be one of a set of specific types (text, vector path, bitmap, etc) as defined in the ISO standard. What you're talking about goes against one of the main purposes of PDF; to optimize quality and file efficiency by rendering each of those object types through different client software routines, and re-using objects as much as is possible.

If you want only two base objects, 'text' and 'everything else', then as explained earlier you will have to export the document without the text as a single image, re-import it and save the result to PDF. Even then, the image will usually be divided into sections for optimal compression.

T

Test Screen Name

Legend

There is no way in Acrobat to merge or simpify vector content. These are not actually layers in PDF terms, and PDF layers are just labels on content: flattening just removes the labels, it doesn't merge the content.

If you have a complicated vector file which takes a long time to draw you have to make a PDF with less vectors in the first place.

M

marcw68715028Author

Participating Frequently

Ok, thanks - so not for vector content.

What about for raster content then? If it was just raster then it would be probably ok. Still seems a little strange that Acrobat can't figure out a way to simplify a PDF to a WYSIWYG option.

Cheers