AECbytes Tips and Tricks Issue
#29 (April 28, 2008)
Turning an Image into Video with Photoshop and After Effects
Scott Onstott Book & Video Author
Although it might sound far fetched, it's now possible to turn a single still photo into a short video that conveys spatial information to the viewer. This technique is most useful in creating establishing or transitional shots within the context of a larger video or animation project. Think of it as a low-budget way to create a high-end effect without having to rent a crane and dolly to give smooth camera motion around a building.
To make it happen you'll need both Photoshop CS3 Extended and After Effects CS3 Professional. We'll use Photoshop's vanishing point filter to create a 3d photo-model and then transfer it to After Effects where we'll animate the 3d virtual camera and output video. Be aware that this technique really works well only on boxy buildings that are oriented as seen below in the original photo.
Open your original photo in Photoshop and choose Filter > Vanishing Point. The Create Plane Tool will be selected by default in the Vanishing Point dialog box. The idea here is to identify a rectangular surface on the building. Click four corner points with the Create Plane Tool and the first plane will be created. Then carefully drag each corner handle to match the photo as best as you can. It is easier to line things up when you zoom in. Press Command+ and Command- to zoom in and out (Ctrl+ and Ctrl- on the PC). The first plane is the most important because it establishes the perspective for the whole model. The plane will turn yellow or even red if Photoshop thinks you're too far off the mark. Don't worry, just re-adjust the four corner handles until the plane is blue.
The first plane has eight handles: four on the corners and four on the edges. Drag the edge handles to resize the first plane so that it covers the building surface entirely. Command-drag (PC: Ctrl-drag) the edge handles to tear off additional planes. New planes are at 90 degree angles to their parent planes. Option-drag (PC: Alt-drag) the edge handles to rotate child planes with respect to their parent planes.
Continue tearing off additional child planes and rotating them to fit the building photo. One trick I've discovered is to tear off an adjacent plane and then rotate it 180 degrees so that you end up with two adjacent coplanar surfaces. In this way, you can make planes that better fit surfaces because there are more edge handles to size to fit. You don't have to make the planes perfectly fit the photo—close is good enough. In the example below, I didn't bother trying to map planes to the projecting sunshade.
When you're satisfied that the geometry you've built effectively covers the building photo, it is time to transfer the photo model to After Effects. Click the Arrow button in the Vanishing Pont dialog box and choose Export for After Effects CS3 (.vpe) and save the file as Bldg.vpe in a project folder on your hard drive.
Launch After Effects and choose File > Import > Vanishing Point (.vpe). Select the Bldg.vpe file that you exported from Photoshop. The Project panel will show the Bldg.vpe node and a folder containing as many .png images as you created planes in Photoshop. Double click the Bldg.vpe node in the Project panel. It will open in a panel of its own at the bottom of the user interface. The Bldg.vpe panel contains animatable tracks for the camera, a parent node, and all of the linked planes.
Observe that the background surrounding the building is black. To make the animation believable, you'll need to put in a photographic background. We will use the original photo itself as its own background. Choose File > Import > File... and select the original photo, which in this case is called Bldg.jpg. The file Bldg.jpg appears in the Project panel. Drag Bldg.jpg to the bottom of the Bldg.vpe panel. Now the photo appears in the background and you can't tell that you're looking at a 3d model on top of a photo.
Next on the agenda is creating some keys to establish the initial state of tracks that you plan to animate. Expand the Camera and Transform nodes and click the time-vary stopwatch icons in the Point of interest and Position tracks. These tracks allow you to animate the camera orbiting and tracking. While you're at it, expand the Bldg.jpg node and its Transform node. Click the Scale track's time-vary stopwatch icon to create an initial key. The red ellipses below indicate the icons to click.
Before you animate, set the duration of the video you wish to make. Click the Arrow button in the upper right of the Bldg.vpe panel and choose Composition Settings from the menu. Set the duration to 0:00:05:00, which mean 5 seconds and zero frames. Click OK to close the Composition Settings dialog box.
The time slider is located at the top of the animatable tracks in the Bldg.vpe panel. Drag the time slider to the last frame of the animation (5 sec in our case). Now we're ready to animate! Using the camera tools on the main toolbar, orbit and track the 3d model to give the building a new perspective angle. The challenge is to orbit and track in such a way that the building in the underlying background remains covered. Don't got overboard—a small transformation is all that is required to impart the sense of motion to this project.
The final touch is to scale the background image over time so it seems like the objects in the distance are moving as the viewer glides around the building. Drag the left edge handle over a short distance to the left to create a key that scales the background image.
Save your After Effects project for future reference by choosing File > Save As and name it Bldg.aep. Finally, export the animation as a video in the format of your choice by selecting one of the options from the File > Export menu.
The finished product is a short video created entirely from the original photo.
Scott Onstott is a book and video author of
AEC software tutorials. He has a degree in architecture
from UC Berkeley and has served as an instructor
there, in addition to working in several prominent
engineering, architecture, and interiors firms
in San Francisco. He has also worked as a technical
editor and technology consultant.
Scott has contributed to over two dozen books
and videos on AutoCAD, Architectural Desktop,
VIZ Render, Revit, 3ds Max, VIZ, Photoshop, Illustrator,
Painter, Fireworks, and Dreamweaver. He can be reached via: www.ScottOnstott.com.
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