Action to Generate Bookmark Report for Multiple PDFs
Rick Borstein has posted an Adobe action file on his blog, Acrobat for Legal Professionals which you can use to export a list of the bookmarks used in multiple PDF files. Click on the link 'Download Create Bookmark Report Action' and download the file with the .sequ extension. Double-click on it and it will be imported into Acrobat.
The action will appear as an option in your Tools menu.
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You browse and select multiple PDFs to process.
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There's an option to select to generate .csv files with a list of the bookmarks.
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The final result gives you a report like this which has .csv files attached for each PDF containing bookmarks.
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Note that this action may cause the .csv files to be incorrectly generated with .pdf extensions if your bookmarks include underscores or other common delimiters.