Yellow Boxes Around some Vector shapes

[Perivan]

Could someone tell me what the yellow boxes that appear around some vector shapes and how to go about removing them, I know I can delete them but this also deletes the vector shape, as this throws the page off centre when resizing content as this sits outside the media box, I can crop the vector shape using the action "crop text line art" but the yellow box stays the same.
PDF sample attached FYI
Thanks
Paul

[loicaigon]

Hi,

You may be interested in this:
https://cdn-www.enfocus.com/manuals/Ref ... 40856.html

Screenshot 2026-03-11 at 11.04.39.png (106.34 KiB) Viewed 86 times

[yosimo]

We already had something like this here in this post:

viewtopic.php?p=18727#p18727

Maybe that can help.

[loicaigon]

Thanks Yosimo for pointing that one. It made me realise that there is something important about "Flatten forms" that was not mentioned over there.
When it "doesn't work", it's mostly because the Form is set as a transparency group. Because results could vary before/after, we don't flatten forms in those cases.
It's easy to remove the Transparency Group Setting both in the UI and in an Action List, but of course it's important to understand how the aspect of the file could dramatically vary.

[Perivan]

Isn't the Select Forms and Flatten forms action relating to variable form fields created in Acrobat and not the "Form" yellow box as in Pitstop.
I've tried the action in one of the links but to no avail.
I can crop the vector shape to the media box but not the "Form" box, which throws out the centering of page content.

[loicaigon]

Ok, I thought I would find a post from Freddy explaining this but not sure there is after all.

One has to understand the difference between Form Fields and Form XObjects.

Form fields are the interactive fields one can enter value in it. This is part of interactive PDFs and you typically don't want them in Print content.
That's why you can find a "Remove Form Fields" or "Flatten Form Fields"

But this is not what you are facing. What you have is a Form XObject, a special kind of object in the PDF Structure. You can see it as a Group of objects, and the yellow bounding box is basically the delimitation of the form that gathers the objects. A form has several interest from being reusable inside a PDF (ex: a logo that would be defined only once in the PDF and referenced over the many pages of the PDF to save file size and optimise performance).

A Form XObject can also have transparency settings to isolate the transparency rendering between the objects that belong to the group and the underlaying content. For example, you could have a front object inside the Form that knocks out objects inside the form, but not objects outside of the Form.

A Form is no particular issue but as some imposition software seem to struggle with Form XObjects, we provided an Action that can extract the objects out of the Form. This is the "Flatten forms" Action (and not "Flatten Form fields). As I mentioned above, keep in mind that this action will produce no results if the Form is set as a transparency group to preserve the rendering of the file.

[Perivan]

I see now, I've just checked the file again and it is part of a transparency group but if I use the action crop line art to media box then select the resulting vector and the form box and group then the form box crops to the size of the media box which would work, my next question is there an action that could group the vector shape with the form rather than have to select each vector and form box seperately in the file.

thanks for your help on this

[loicaigon]

If the line art extends beyond the mediabox, the crop line art Action should crop that object even if in a form.
The form itself is not cropped to the mediabox, but it doesn't really matter.
If you are troubled by the form being beyond the Mediabox, you either want to remove it (Flatten Form), or edit the form manually (See PitStop Edit Tools / Edit Form)