MAKING AND USING DISPLACEMENT MAPS Creating a Displacement Map The Displacement Map Effect plug in in After Effects uses the varying levels of grey in the map image to move the image up and to the right, while the darker areas will move areas of the image down and to the left. To create the displacement map image we need to create an image first in Photoshop. Make the image 720 by 576px, in grayscale mode.Apply the clouds filter to the image Filter>Render>Clouds thus creating a random pattern of light to dark. To tile the image, as with the texture map, apply the Offset Filter Filter>Other>Offset and set the horizontal to about 350px and check the wrap around option. Using the clone stamp tool edit out the line down the centre. The more contrast an image has the more violent the motion will be.If you want the motion to be gentle you can apply a Gaussian Blur. Save as a .jpg file

APPLYING THE DISPLACEMENT MAP TO AN IMAGE Create a new project in After Effects and make a new composition. Select the presets as below, PAL D1/DV, image size 720x576px and duration 5 seconds. In this exercise we will be working on a frame aspect ratio of 4:3,this is for a square screen TV monitor.

You will need an image to be your target layer ie. the layer which will contain the effect. An ideal image would be water, trees or one of the texture images in your texture archive saved as a .jpg. Import your .jpg file and the cloud image just created. This will be the displacement map layer which will serve as the effect source. Place each file into the layer section of the timeline window with the target layer above. Switch off the eye so the displacement map layer doesn’t appear in the output. Now we will set the displacement map in motion. Select the Clouds layer in the Timeline window. Apply Offset filter Effects>Distort>Offset . Make sure the Current Time Indicator is set at frame 1 in the Timeline window.

Click the stopwatch by the Shift Centre option, this sets beginning and end points for the motion of the displacement map image. Move the Current Time Indicator on the Timeline to the end frame position. In the effects window drag the horizontal position of the Shift Center option to the right by clicking on the figure to the left and dragging to the right you will see it increase. Increasing by around 1000 will bring it round so it wraps around to form a continuous loop. Here you can see the reason for tiling. At this point you can do a RAM preview to check the speed at which the loop is moving

Once you are satisfied with the speed of the loop create a pre-composition by selecting Layer>Pre-compose and check options Move All Attributes Into The New Composition and Open New Composition selected. This will treat the displacement map layer as a continuous loop animation in one layer of Comp 1. Hide the Pre-comp layer in the Timeline by clicking off the eye icon. The displacement map doesn’t need to be visible to work.

Go back to Comp 1 in the project window and click on your target layer. Adjust the size of the image to slightly larger than the live area of the project window. You can just pull the scaling handles usually shown in pink around the image. Apply the displacement map effect to the target layer by selecting Effects>Distort>Displacement Map. Select the source displacement map image from the selector, choosing the Pre-comp layer name. Use luminance for both horizontal and vertical displacements and set max pixel movement to 15 for both. Increasing or decreasing these numbers controls the amount of movement you wish to have in your animation. Run a RAM preview and adjust speed and pixel displacement if necessary.

SIMPLE MASKING If you do not want to displace the entire image, part of the image can be masked so the effect is only applied to a portion of the screen. To do this open your displacement map composition in the Comp window. Add a solid layer Layer>New>Solid and set the colour to 50% grey. To add a simple gradient mask use a Linear Wipe. Effect>Transitions>Linear Wipe. Set the wipe angle to 0 and the transition completion to 30%. Changing the feather affects the smoothness of the transition

Gradient mask using a Linear Wipe