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Loop ItA beginners guide to creating a seamless looping background in Adobe After Effects
It is times like these when I pull together some of the basics of Adobe After Effects to quickly create some amazing animated backgrounds that make the clients say, "WOW!!" For this particular project, we'll create a soft looping undulating background with text and other graphical elements composited on top. This particular effect is being used on just about every television network and it is very simple to put together. This is a fairly common task, and there are many versions of how to create one of these floating around the Internet.
In part one of this exercise we'll create a seamless looping background to use in various video projects. In part two, will apply the other elements. While this exercise is aimed at beginners, others may be able to modify this for their own uses.
|Click HERE to download image sequence|
1. To begin, we are going to create five images in Photoshop. Create a new image at the correct frame size (720x480 in this case). Use any color scheme you like. Because this project was client based I used their colors of gold and black.
2. There are several methods for creating a background, but one of the fastest and easiest is to use Render/Clouds. This doesn't quite look like the soft background we had in mind, but we can quickly fix this by applying a Gaussian Blur and setting the blur amount quite high (20 pixels in this example).
3. Save the image as image1.tga or other format of your choice.
4. Without creating a new image simply repeat the Render/Clouds - Gaussian Blur process again. This will keep the fractal clouds from repeating themselves. Save this new image as image2.tga.
5. Repeat this three more times until you have five images.
6. Open Adobe After Effects, create a new project with the following settings:
Frame aspect - 720x480
Frame rate - 30fps
Duration - 30 seconds
7. Import the images we just created into the project (Ctrl+I). Select your first image, and then check the sequence box. This will allow After Effects to recognize your images as an "animated" sequence rather than just a still image.
8. Because there are only five frames at the current frame rate this sequence only lasts a fraction of a second. We need to make adjustments targa sequence so that it runs at .5fps instead of 30fps. Using the right mouse button (Command key on the Mac), click on the targa sequence in the project window and open the Interpret Footage/Main window (Ctrl+Shift+H). This menu allows the user to change the parameters of any imported file. This method will allow you to speed up a sequence, or in our case slow it down. We will want our sequence to run over 10 seconds instead of 5 frames, so change the Assume Frame Rate to .5 Frame Per Second.
9. Because we are using Frame Blending for this project, the first frame and the last frame need to reference each other to blend properly, so loop the sequence 3 times instead of 1, and click on OK. If you click on the image sequence now, you will notice that it is now 10 seconds long instead of 5 frames.
10. Drag the sequence from the Project Window to the Composition Timeline Source Name column. You can also drag the sequence directly into the Composition Window.
11. For this process we are only concerned about rendering the second loop in sequence. Click on the Current Time indicator to edit our position in the timeline, and change the time to 10:00 (the start of the second loop). The timeline indicator will move to the 10:00 second mark.
12. Move the In Point marker to the 10:00 second mark.
13. Change the Current Time to 19:29 (the end of the second loop) and move the out point marker to that position.
14. If you move the timeline indicator back to the ten-second mark and hit the spacebar, the program will play the file back. When it gets to the next image in the sequence it jumps instead of blends like we want it to.
15. Press the spacebar again to stop playback.
16. We need to blend these images together. If you look in the second column of the Timeline window you will see a selection for Enabling Frame Blending. Put a check in that box. This will allow for frame blending for this layer only.
17. Frame Blending basically takes the each frame in a particular layer and blends them together to smear or smudge the image. Frame Blending is also helpful if you are doing any time remapping of video.
18. Frame blending takes a long time to compute, and because we are going to add more elements into background (other images, text, etc). It would take an enormous amount of time to render out all of the effects. It is much easier to render out this composition as a movie, and then import the movie file into another composition later.
19. Make a movie and save it in the movie format of your choice. For this project I chose an uncompressed QuickTime file at full resolution. Granted this can eat up a lot of hard drive space, but it is worth it in the time it will save when you have to render all of your other layers.
20. Make sure that you have Frame Blending on for all checked layers.
21. If you are unsure if your In and Out points are set correctly check the Time Span, and make sure it is set to Work Area Only. If the in and out points are not at 10:00 and 19:29, click on the Set button and make the adjustments. The duration should be ten seconds.
|Click image to view final looping animation|
22. Once you have made the necessary adjustments click on the render button and sit back and wait. Depending on your computer speed it may take a while, remember frame blending is a processor intensive task. The good news is with most of us running at 800MHz and higher this should take less than three minutes to complete. Just time enough to run and get a nice refreshing sparkling water or natural fruit juice.
When the movie is finished rendering, you will have a nice looping background that we will use in the next part of this tutorial.
Stephen Schleicher is a well known writer, visual effects artist and media guru! You can see more of Stephen at
www.majorspoilers.com and www.stephenschleicher.com
Related Keywords:Adobe After Effects, Looping animation, animation, stephen schleicher, tutorial
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