Photographs add interest and dimension to PowerPoint material; on some occasions, they can also detract from your content if the image contrasts too starkly with text or provides varying depths of field. Blurring the background -- or any other portions of a photograph -- can bring selective focus to important parts on the slide. PowerPoint 2010 has introduced new graphic effects that were once limited to a specialised software like Photoshop, but now, you can apply artistic effects, such as a blur, to photographs without leaving PowerPoint.
Open the PowerPoint presentation in which you want to create a blur effect.
Insert a photograph into your slide by clicking on the "Insert" tab, then click the "Picture" button in the images group. Navigate to your picture when the "Insert Picture" dialogue box opens, then click "Insert."
Select the picture that has been inserted into your slide by clicking on it. Click on the "Adjust" group, then the "Picture Tools" tab, then the "Format" tab.
Click on "Artistic Effects" then select the "Blur" option, located to the far right on the 2nd row of the window. Click on "Radius" to change the blur. Experiment by increasing and decreasing the percentage of the blur effect to achieve the desired blur. Click "Close."