Flattener

User Guide — Mapsoft Flattener Plugin for Adobe Acrobat

Overview

Flattener is an Adobe Acrobat plug-in that removes or flattens interactive PDF elements — annotations, form fields, markup, stamps, multimedia, and other non-static content — into the page’s static content stream. This converts a dynamic, interactive PDF into a clean, flat document where all visual elements are permanently embedded as part of the page content.

Flattening is essential in many workflows: preparing documents for archival where interactive elements must be preserved as static visuals, removing sensitive comments and markup before distribution, locking down form fields so they cannot be edited, or stripping multimedia content for compliance with regulatory submission requirements. Flattener gives you granular control over exactly which element types to flatten or remove, and optionally places flattened content onto named PDF layers (Optional Content Groups) for organizational clarity.

The plug-in is available in three variants: an Acrobat plug-in (MAPSFLATTENER.api), a COM automation DLL for scripted workflows, and a workflow server library (.lpi) for the Mapsoft Workflow Server. It also includes a Remove All button for quickly selecting all annotation and markup types at once.

Getting Started

After installation, Flattener adds a menu item to Adobe Acrobat. To open the dialog:

1. Open a PDF document in Adobe Acrobat.
2. Go to Extensions › Mapsoft › Flattener.
3. The Flattener dialog will appear with checkboxes for each annotation and markup type, layer options, and configuration management controls.

Select the element types you wish to flatten or remove, configure any layer options, and click OK to process the document. The flattening operation iterates through every page, examining each annotation and converting selected types into static page content. Remember to save the document after flattening to preserve the changes.

While the document is processed, a progress window shows the current page and annotation count. Heavily annotated documents — CAD drawings can carry thousands of markup annotations on a single sheet — may take a little while, and the progress window keeps you informed throughout. Click Cancel to stop early: the page currently being processed is finished cleanly, and you can use File › Revert to discard the partial changes if required.

Annotation Types

The dialog provides individual checkboxes for each annotation type that Flattener can process. Check the types you want to flatten or remove:

Markup Flattening

In addition to annotation types, Flattener handles markup and drawing annotations that reviewers add during document review. Each markup type has its own checkbox:

When markup annotations are flattened, their visual appearance (lines, shapes, highlights) is rendered into the page content stream as static vector graphics. The annotation object itself is then removed — together with its associated pop-up note window — so the markup can no longer be selected, edited, or deleted by users viewing the document.

Flattener renders markup faithfully even in PDFs produced by CAD packages and other non-Adobe tools. Annotations written without an appearance stream (common for rectangles, circles, lines, polylines, polygons and ink created by CAD exporters) are reconstructed from their geometry, border and colour settings, and rotated or scaled appearances are placed exactly as the originating application displayed them. Annotations whose appearance cannot be reproduced are left untouched rather than being removed, so no visible content is ever lost.

CAD Drawings & Searchable Text

PDFs exported from CAD packages such as AutoCAD often contain invisible rectangle annotations that carry the drawing’s SHX text as comment text. These annotations draw nothing on the page — their only purpose is to make the drawing’s lettering searchable in Acrobat. Because they have no visible appearance, flattening removes them, and without further action the drawing text would no longer be searchable in the flattened document.

Keep Text of Invisible CAD Text Markup Searchable

Enable Keep text of invisible CAD text markup searchable (beneath the layer options) to preserve that text. When an invisible text-carrier annotation is flattened away, the text it carries is written into the page as invisible text placed over the annotation’s original location. The page looks exactly the same, but search, text selection, copying and indexing continue to find the drawing text in any PDF viewer — the same technique used by OCR “searchable image” tools.

Layer Options

Flattener can optionally place flattened annotation content onto named PDF layers (Optional Content Groups, or OCGs) rather than merging it directly into the main page content. This provides a way to organize flattened content while still rendering it as static graphics.

Add Flattened Content to Layer

When the Add Flattened Content to Layer option is enabled, flattened annotations are placed onto dedicated layers. You can then control layer visibility in Acrobat’s Layers panel. If a layer with the target name already exists in the document, the flattened content is added to it; otherwise, a new layer is created automatically.

Layer Categories

Flattened content is organized into up to five layer categories, each with its own enable/disable checkbox and its own separately named layer in Acrobat’s Layers panel:

• Comments & Markup — FreeText, lines, shapes, highlights, strikeouts, underlines, ink, polygons, and text edits, on a layer named Markup and Comments.
• Notes — Sticky note annotations, on a layer named Notes.
• Stamps / Watermarks — Rubber stamp and watermark annotations, on a layer named Stamps and Watermarks.
• Media — Movie, screen, rich media, and sound annotations, on a layer named Media.
• Other — File attachments, 3D content, and other annotation types not covered by the categories above, on a layer named Other.

Each category can be independently assigned to its layer, so you can, for example, switch the display of flattened stamps on and off separately from flattened markup. If a category’s layer checkbox is unchecked, that type of flattened content is placed directly into the page content stream without layer assignment.

Saved Configurations

Flattener supports named configuration presets so you can save and recall complex flattening setups. Each preset stores all checkbox states, layer options, and page selection settings.

Saving a Configuration

Type a name in the Configuration drop-down and click Save. All current settings are stored in the plug-in’s INI file. If a configuration with the same name already exists, you will be prompted to confirm the overwrite.

Loading a Configuration

Select a saved configuration from the drop-down list. All checkboxes and options are restored to the dialog. This is particularly useful when you have different flattening profiles for different document types — for example, a “Remove All Markup” preset that checks all markup types, or a “Forms Only” preset that only flattens form fields.

Removing a Configuration

Select a configuration and click Remove to permanently delete it from the INI file.

COM Automation

Flattener exposes a COM automation interface (IFlattenerAuto) that allows external applications to invoke flattening programmatically. This is available in the Automation build variant, installed as MAPSFLATTENER.dll.

The COM interface mirrors the dialog options with properties for each annotation and markup type, plus a Flatten() method that executes the operation on a specified PDF document handle. This allows VBScript, PowerShell, C#, and other COM-aware languages to automate flattening as part of larger document processing workflows.

Key COM interface members include:

• Boolean properties for each annotation type (notes, form fields, stamps, movies, sounds, file attachments, links, 3D, redactions).
• Boolean properties for each markup type (free text, lines, squares, circles, highlights, strikeouts, underlines, ink, pencil, polygonal lines, polygons, text edits).
• Layer control properties for enabling layer placement and selecting which categories go to layers.
• The Flatten() method to execute the operation.

System Requirements

• Adobe Acrobat: Acrobat Pro or Standard DC (2017 or later). Not compatible with Acrobat Reader.
• Operating System: Windows 10 or Windows 11 (32-bit and 64-bit Acrobat installations both supported).
• Acrobat Version: Some markup types (polygonal lines, polygons, text edits) require Acrobat 6 or later. The layer placement feature requires PDF 1.5+ support.
• COM Automation: The automation variant requires registration via regsvr32 and is typically installed by the Mapsoft Workflow Server installer.

Support

If you encounter a problem or have a question not covered here, please get in touch:

• Contact Mapsoft
• Support page

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