All images are from Producing Independent 2D Character Animation: Making and Selling a Short Film by Mark Simon. Reprinted with permission.

This is the seventh in a series of 12 excerpts from Mark Simon’s book, Producing Independent 2D Character Animation: Making and Selling a Short Film. This book is a full-color, concept-to-pitch guide that teaches animators, students and small studios the art and business of producing short, cel animated films. Animation producer Mark Simon has detailed the process in an accessible how-to manner using his award-winning series, Timmy’s Lessons In Nature, as a guide. This 432-page book contains more than 600 full-color images, interviews and a CD-ROM containing sample animation, animatics and sample software described in the text.

The art of rotoscoping consists of drawing over live-action to produce your animation. The purpose of rotoscoping is either to animate a scene completely using a live-action reference, or to add animation to a live-action scene while tracking the movement of the camera and the live-action elements. More and more rotoscoping is done these days to produce mattes of elements, also known as rotomatting, within a live-action shot either to remove unwanted elements or to add special effects.

For example, if we wanted to visually remove the legs from the character in Figure 1, we would pull a matte of his legs. The matte would consist of drawing an outline tightly around the outside of his legs. His legs are now the elements that we may remove or add effects to. In order to remove his legs, we would need a clean shot of the background without the character. The leg elements then would be replaced by portions of the clean background.

[Figure 1] Rotoscope template in CorelDraw. The image snaps to the corner of the guidelines, and the crosshairs allow us to line up the images when taping on the animation header strips.

There are a number of different ways to rotoscope, and a few of them produce completely different results. Rotoscoping may be used to create a completely realistic motion, or as a test to study motion. Animators who shoot live-action footage and just use it for research are not actually rotoscoping; they are simply using live-action reference for inspiration.

When you are shooting footage for rotoscoping, set your film or video camera to a fast shutter speed. Accurate movement is what you are looking for, and fast movements with a slow shutter will be blurred.

Rotoscoping always starts with storyboarding and then filming live-action of the shot you need. If you are shooting with film, you will need the frames scanned and saved as digital sequential files. If you are shooting with video, you will need to be able to capture the scene onto a computer or move a frame at a time with your video player. Some software allows you to rotoscope directly within the program. Figure 1 shows a video frame captured in Adobe Premiere, exported as a .TGA file and imported into CorelDraw.

An accurate way to rotoscope is either to paint within a software package or print the frames you need and trace over them on a light table.

To rotoscope with software or to print the frames you need, you should first digitize your video footage. Digital cameras can connect to computers via their firewire connection. There are many video cards that will capture your analog footage through RCA, BNC or S-Video connections. Once you’ve captured your video into your computer, you can export the video file from your editing or compositing program as individual sequential files. In other words, export the frames as .jpg or .tif extensions, such as roto-01.jpg, roto-02.jpg, and so on. NTSC video runs at 30fps. To cut down your work, you can reduce the video to 15fps. This will be the same as animating on twos (two frames for every one drawing).