Editing an image in Office doesn’t hide the original details of the photo.
In our piece on the Word Redaction Tool we mentioned that images in the document could be fully redacted by changing the image into a black box.
But what if only want to hide/redact part of the image? That’s possible with the image editing tools in recent versions of Office but there’s a trap.
The trap is the redaction is done by adding layers over the original image. Office doesn’t have a way to merge or flatten the layers into a single image. So it’s useless as a redaction tool and, to be fair, the tools were never designed for redaction.
If you’re familiar with another image editor then it may be easier to copy the image from an Office document into the editor, make the changes/redactions. Finally paste the edited image back into the document to replace the original picture. See Redacting Images and PDF’s for more details.
Image Redaction in Office
Here’s how the image editing works within Office. Start with an image, in this case with Word.
Choose Insert | Shapes and select an appropriate shape. We’ll use the oval because we’re hiding faces.
Click over the image to insert the shape then drag it around until it’s in the right position. Use the edge points to resize the shape to match what you need.
When you select the shape, the Drawing Tools | Format tab will appear. The default fill color (blue in this case) can be changed from either the Format Shape Styles | Shape Fill pull-down or one of the black shape styles in the gallery.
Tip: once you’ve setup the first object, you can clone it for other places in the document. Select the shape, choose Copy then Paste (Ctrl + C then Ctrl + V) to add a copy that you can move and resize.
Here’s the end result with oval, circle and rectangle shapes.
But the image isn’t truly redacted. It’s just an image with shapes placed over it. If you sent this document to someone, they could easily delete or hide the shapes to see the original.
Office has no way to merge the objects into a single image. The Group command only links objects so they can be managed together.
The quick and easy workaround is to take a screen-shot of the redacted/edited image and paste that screen image back into the document; replacing the edited image with shape overlays.
Warning: saving the document to PDF is NOT an answer. Word’s conversion to PDF retains the original image. We tested this by selecting the image in the converted PDF and copying it.
The pasted image is just the original without the overlaying shapes!