How To Split and Merge

Merge or flatten layers

Merged layers acquire the properties of the layer into which they are merged (the target layer). Flattening PDF layers hides any content that is not visible when the flattening operation is executed and consolidates all layers.

Important: You cannot undo either a merging or a flattening operation.

Merge layers

1. Click the Layers button, and select Merge Layers from the Options menu.
2. In the left pane (Layers To Be Merged), select one or more layers to be merged. Ctrl/Command-click to select multiple layers, and click Add. Click Add All to merge all layers.
3. To remove a layer from the center panel, select the layer or layers. Ctrl/Command-click to select multiple layers. When your selection is complete, click Remove.
4. In the right pane (Layer To Be Merged Into), select the layer into which to merge the selected layers, and click OK.

Flatten layers

Click the Layers button, and select Flatten Layers from the Options menu.

Source：Adobe

Add layer navigation

You can add links and destinations to layers, allowing you to change the view of a document when the user clicks a bookmark or link.

Note: In general, changes to layer visibility made using the eye icon in the Layers panel are not recorded in the Navigation toolbar.

Associate layer visibility with bookmarks

1. Set the required layer properties, visibility, and magnification level for the target PDF layer in the document pane.
2. Click the Bookmarks button, and choose New Bookmark from the Options menu.
3. Select the new bookmark, and choose Properties from the Options menu.
4. In the Bookmark Properties dialog box, click the Actions tab.
5. For Select Action, choose Set Layer Visibility, click Add, and then click OK.
6. Select the bookmark label in the Bookmarks panel, and name the bookmark.

Associate layer visibility with a link destination

1. Set the required layer properties for the destination in the document pane.
2. Choose View > Navigation Panels > Destinations.

   The Destination panel appears in a floating panel. You can add it to the other panels by dragging it to the navigation pane. If the panel is collapsed, click the Destinations button to expand it.

3. Click the Create New Destination button or select New Destination from the Options menu, and name the destination.
4. Select the Link tool , and drag in the document pane to create a link. (Because content is added to all layers, it doesn’t matter that you are apparently creating the link on the target layer. The link works from any layer.)
5. In the Create Link dialog box, select Custom Link and click Next.
6. Click the Appearance tab in the Link Properties dialog box, and set the appearance of the link.
7. Click the Actions tab in the Link Properties dialog box, choose Set Layer Visibility, and click Add.
8. Close the dialog boxes.
   
   You can test the link by changing the layer settings, selecting the Hand tool, and clicking the link.

Source: Adobe

Edit layer properties

You can combine the default state setting, the visibility setting, and the print setting to control when a layer is visible and when it prints. If a layer contains a watermark, for example, you may want the layer to not show on-screen but always to print and always to export to other applications. In this case you can set the default state to on, the initial visibility to never visible (the image doesn’t show on-screen), and the initial print and initial export states to always print and always export. The layer need not be listed in the Layers panel, since all the state changes are handled automatically.

Note: The settings in the Layer Properties dialog box take effect only if Allow Layer State To Be Set By User Information is selected in the Documents preferences. If it is not selected, Layer Properties dialog box settings, other than Layer Name and Default State, are ignored.

1. Click the Layers button in the navigation pane.
2. Select a layer, and choose Layer Properties from the Options menu.
3. In the Layer Properties dialog box, edit the layer name or any of the following properties, and then click OK:

   Option				Description
   Default State				Defines the initial visibility state of the layer when a document is first opened or when the initial visibility is reset. The eye icons for layers are initially shown or hidden based on this value. For example, if this value is set to off, the eye icon for a layer is hidden when the document is first opened or when Reset To Initial Visibility is chosen from the Options menu.
   Intent				Select View to allow the layer to be turned on or off, or select Reference to keep the layer on at all times and permit editing of the properties. When the Reference Intent option is selected, the layer appears in italics.
   Visibility				Defines the on-screen visibility of the PDF layer. You can show a layer when the document is opened, you can hide a layer when the document is opened, or you can let the default state determine whether a layer is shown or hidden when the document is opened.
   Print				Determines whether a layer will print.
   Export				Determines whether the layer appears in the resulting document when the PDF file is exported to an application or file format that supports layers. Any additional properties that the creator of the layered PDF has associated with a specific layer are shown in the box at the bottom of the Layer Properties dialog box.

Source: Adobe

Make a PDF EBook with Adobe Acrobat

About PDF Layers

Acrobat supports viewing, navigating, and printing layered content in PDFs created from applications such as InDesign, AutoCAD, and Visio.

You can control the display of layers using the default and initial state settings. For example, if your document contains a copyright notice, you can easily hide the layer containing that notice whenever the document is displayed on-screen while ensuring that the layer always prints.

You can rename and merge layers, change the properties of layers, and add actions to layers. You can also lock layers to prevent them from being hidden.

Acrobat does not allow you to author layers that change visibility according to the zoom level. However, you can highlight a portion of a layer that is especially important by creating a bookmark that magnifies or hides the layer using page actions. You can also add links that let users click a visible or invisible link to navigate to or zoom in on a layer.

To retain layers when you convert InDesign CS or later documents to PDF, make sure that Compatibility is set to Acrobat 6 (PDF 1.5) and that Create Acrobat Layers is selected in the Export PDF dialog box.

Source - Adobe

Edit document metadata

PDF documents created in Acrobat 5.0 or later contain document metadata in XML format. Metadata includes information about the document and its contents, such as the author’s name, keywords, and copyright information, that can be used by search utilities. The document metadata contains (but is not limited to) information that also appears in the Description tab of the Document Properties dialog box. Document metadata can be extended and modified using third-party products.

The Extensible Metadata Platform (XMP) provides Adobe applications with a common XML framework that standardizes the creation, processing, and interchange of document metadata across publishing workflows. You can save and import the document metadata XML source code in XMP format, making it easy to share metadata among different documents. You can also save document metadata to a Metadata template that you can reuse in Acrobat.

Source: Adobe