Layouts Effects Layouts Layouts Layouts Layouts Layouts Layouts

Photo to Movie Blog

Using Adaptive Blur and Motion Blur

Posted March 12th, 2010 by Chris

Photo to Movie has always included a feature called adaptive blurring for reducing flickering/flashing in your movie due to aliasing effects.

Slow motion on photos with lots of detail such as a photo of a tree or water from a distance exhibit this problem most severely.

In the past, adaptive blur processing had to be enabled on a document-wide basis. Photo to Movie 4.5 will include the ability to control this processing on a photo by photo basis.

In addition, Photo to Movie 4.5 will introduce a feature called motion blurring.

Scaling Photos

When Photo to Movie scales down a photo from it’s full size, it must choose which pixels from the original image to use in the final scaled image. As Photo to Movie creates motion by smoothly moving and scaling the key frames, it is possible that a bright pixel in the source image will be chosen on one frame but not on the next frame. This leads to a flickering/flashing effect (the bright pixel will be included every other frame, leading to flashing).

The solution in Photo to Movie is to perform processing to make the selection of pixels in the original image consistent from frame to frame. It does this by blurring the original photo just enough to blur out a pesky bright pixel, but (ideally) not enough to make the photo look blurry.

The processing does come at a cost, however. Even though Photo to Movie is only doing a slight (approximately 1/2 pixel) blurring in the photo, it “softens” the photo. Some users would like to retain the original sharpness of their photo.

The flickering problem is most pronounced on slow movement; photos displayed with fast motion (i.e. key frames are wide apart) do not have as much of a problem since the problematic bright pixel will be separated by several pixels in the final movie, so the eye won’t pick out any flickering.

Adaptive Blur

In versions prior to Photo to Movie 4.5, adaptive blur had to be enabled on a document-wide basis. You changed it in the Make Movie dialog with the ‘Higher Quality’ vs. ‘Faster Export’ menu item.

In Photo to Movie 4.5, you can control the adaptive blur for each photo. If a photo needs to be sharper and the motion is fast enough, you can completely disable it for just that particular photo.

The default setting is still Medium (which corresponds to the setting in earlier versions). But you have the option of setting the adaptive blur processing to None, Light, Medium, or Heavy on a photo by photo basis.

In Photo to Movie 4.5, you can access this setting by clicking on your photo in the timeline. Then in the inspector, choose the ‘Photo’ tab and select your desired adaptive blur setting. The individual photo setting is not available in versions prior to Photo to Movie 4.5.


The image above is a great example of a problem image. Try downloading the original image, putting two large key frames on the photo (I used 3118×1753 for each). Then render using a high quality codec such as QuickTime/Animation to a video sized 852×480. Try it with adaptive blur enabled and disabled. You’ll spot the difference right away.

Link to original photo on

Motion Blur

In addition to adaptive blur, Photo to Movie 4.5 also includes a document-wide setting (in Make Movie) for adding motion blur to your movie.

Motion blur is done by taking every movie frame and splitting it into several shorter (time) frames and then adding all of those frames together. The effect is that in areas with a lot of motion, you get a blurring effect similar to what you would get with a physical movie camera. In areas with little motion, there is little or no blurring. It gives a more natural look to the motion in your slide show.

The effect is enabled in the Make Movie dialog and it defaults to ‘disabled’.

Here is a sample frame from a movie with motion blur enabled on a fast rotation. Notice the center of the image is not blurred; but the edges, where the most motion is occurring, are blurred.


Comments are closed.