Research Imaging Solutions. goo.gl/yp8j3c. extracting figures from PDFs

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1 Research Imaging Solutions goo.gl/yp8j3c extracting figures from PDFs

2 Research Imaging Solutions goo.gl/yp8j3c handouts training consulting Beth Beighlie Digital Imaging Coordinator Research Imaging Solutions Information Technology Department Harvard Medical School 220 Longwood Avenue Boston, MA (617) Written by Beth Beighlie Copyright 2011 by Research Imaging Solutions version 2, May 5, 2016

3 ... 4 Option 1: Photos, Micrographs, X-Rays and Scans: Opening a PDF with Adobe Photoshop... 5 Option 2: Tables, Charts, Graphs and Drawing Objects: Exporting to a Microsoft Word Document... 6 Option 3: when all else fails use the Snapshot Tool... 9

4 Extracting Figures From a PDF In order to better understand the concepts contained within this document, download these documents: (Google: research imaging solutions handouts & guides) Imaging Essentials Creating Figures This document cannot be offered without stating the obvious: If you did not author the PDF you are extracting figures from, think about if what you are doing is ethical and legal. Do not plagiarize. Generally, the best way to use figures that are contained within a PDF document is to go to the original image file. The original file should be understood to mean the master image file, not images contained in a Word document, PowerPoint presentation, or an edited or modified image file. PDF documents aren t the best source for images because the PDF file format is the last stop for document creation. It is a file format best suited for reading and reviewing and to a limited extent, commenting. It is not a file format that lends itself to editing, nor one that is good for stripping out graphic content like tables, charts, graphs, figures, photos, micrographs, etc. Suppose you are unable to locate or access the original figure. You might be able to get at some of the image content of a PDF, but the results can be unreliable and blurry, and you will almost certainly need to modify the figure before using it. Modifications might include resizing the physical dimension &/or resolution of raster images, adding captions or headings, changing font size, style and placement of text within charts. It is helpful to approach the project with the understanding that it could take some time to achieve a quality figure- this may compel you to try to locate the original artwork that was the source of the figures, rather than try to extract graphic content from the PDF.

5 Option 1: Photos, Micrographs, X-Rays and Scans: Opening a PDF with Adobe Photoshop How to open raster images that are contained within a PDF by using Adobe Photoshop [Tools you ll need: Adobe Photoshop; an understanding of the difference between raster images and vector objects, as described in Imaging Essentials handout] This method will open any raster image at the resolution the author used when creating the document. If the graphic is vector based, this option will not be available to you (read the 1st page or 2 of Imaging Essentials on how to ID a raster). If the figure you wish to use is a raster image, you can use Photoshop to open the PDF. This method will usually give you a higher quality image than the Snapshot Tool. It will export the image at the same resolution that the author used when constructing the figure. If the figure is part of a journal article, you can assume that the resolution is considerably better than the 72dpi that the Snapshot Tool captures. Expect to still do some editing to get the correct resolution, physical dimension, file type and color mode. How to do it Open Adobe Photoshop From the Menu Bar, go to File > Open and navigate to the PDF you want to cannibalize. In the resulting Import PDF dialog box, select the Images Radio Button. Then select which Image(s) you d like to Import. 5

6 Option 2: Tables, Charts, Graphs and Drawing Objects: Exporting to a Microsoft Word Document Use this for tables, graphs, charts and some other vector objects [Tools you ll need: Adobe Acrobat Full or Professional version, NOT Reader; Microsoft Office 2003 or Office 2007 or Office 2008 will not work for this task.] Remember, it is far better to use the original document- the Word document the PDF was created from, the Excel document that generated the chart or the PowerPoint slide that contains the illustration. If you are unable to access the original document and instead choose to use the steps outlined here, be sure to proofread the results very carefully. Formatting, fill colors and labels can be rendered inaccurately. Raster-based graphics do not Export or Save As well, if at all. If you intend to create a new figure using these elements, PowerPoint is the easiest tool for the task. 6

7 How to do it From the Menu Bar, go to File > Save As or Export. If doing a Save As, choose Word Document as the File Format. It doesn t matter whether you Export or Save As, the same process is applied to the document. In the resulting Word Document, if you are extracting a vector, such as a table, chart, graph or drawing object, select it as you would select any object. 7

8 Next, go to your target document- the document or presentation you are creating the new figure with and Paste Special the object (don t do a regular Paste, or you will not only get awful looking objects, but you will also diminish the editing options). If using a Mac, choose Picture If using a PC, choose Picture (Enhanced Metafile) or Picture (Windows Metafile) If it is necessary to edit particular elements within the object, Ungrouping the object will enable certain editing features. Once you are done editing the ungrouped object, it is a good idea to Group it again. You may find that there is so much editing to be done; it may be easier to rebuild the object from scratch. Or it may trigger your memory about where to find the original document. 8

9 Option 3: when all else fails use the Snapshot Tool This is the least attractive option: graphics produced by this method are low-resolution raster files [Tools you ll need: Adobe Acrobat Full or Professional version, NOT Reader; any pixel editing application like Adobe Photoshop or GIMP] The Snapshot Tool within Adobe Acrobat will allow you to take a screen shot of the document. It creates a screen capture, made up entirely of pixels at a very low resolution (72dpi). It s quick, it s easy, it s blurry and probably not suitable for printing or resizing larger. It may not even be suitable for low resolution uses like PowerPoint projection. If you are capturing anything that includes text or high contrast edges that are inherent in cartoons, charts, graphs, tables, etc, you will see jagged, blurry edges. The Snapshot Tool is a little more forgiving when used with photos or micrographs, as long as there is no annotation or text. It may be useful to zoom in or enlarge the viewable area as much as possible when using the Snapshot Tool. How to do it In Adobe Acrobat, using the Menu Bar, go to Tools > Select & Zoom > Snapshot Tool. After Snapshooting a selection, open a pixel-based image editing application, like Adobe Photoshop or GIMP. Paste into Photoshop or GIMP and the Snapshot will appear. Edit the image to the proper physical dimension and resolution. If the image is sufficiently large, you may be able to increase the resolution according to the instructions for Resizing Images within the Imaging Essentials guide. While these recommendations will never replicate the quality of a figure created from original artwork, or even from some existing Word or PowerPoint document, it may be the only option available. If you do choose any of these options, take care to proofread the results. 9