Create animation on your videos

Even if you don’t know what rotoscoping is, you’re probably familiar with how it looks.

Rotoscoping is an animation technique developed throughout the 20th century and used in movies such as Snow White and the Seven Dwarves.

It involves tracing individual frames of film footage; a popular rotoscoping technique employed in movie title sequences is to dissolve from the rotoscoped animation into the ‘real’ footage on which it’s based.

Digital technology has expanded the scope of rotoscoping and now the term applies to all techniques that trace or overlay graphics onto movie footage. Probably one of the best-known and most-watched rotoscope special effects is the Star Wars lightsaber glow. This is also a popular theme for amateur movie editors, as the ‘star wars kid’ and other amateur spoof videos have demonstrated.

Some video-editing applications have built-in rotoscoping tools, but for ‘real’ rotoscoping and access to the range of versatile creative effects it provides, you need to export video from your video editor as individual frames. Given that Pal DV records at 25 frames per second, it doesn’t take long to work out that rotoscoping can be time consuming.

By making use of automation features you can reduce the workload. But the best way to save time and ensure a successful outcome is to plan and be realistic. If you need to export and import frames one by one or you plan to hand-edit each frame, keep the effect short. A two-second rotoscoped effect will involve exporting, editing and re-importing 50 frames.

First, catch your frames
To work on individual frames of a movie, you first need to export them from your video-editing application in a suitable format for opening and editing in an image editor.

One application that does this very well is Adobe Premiere Elements 2.0, which allows you to export a movie or section of the timeline as a filmstrip (.flm) file, or a sequence of still image files in Jpeg, Tiff or various other formats. If your video editor can’t export or import image sequences all is not lost – you can usually save and load individual frames. I’ll explain how to do this later.

A filmstrip file opens in Photoshop or Photoshop Elements as exactly that – a long strip of sequential frames. You can work on each frame, resave the file and import it back into Premiere Elements.

One of the advantages of .flm files is that they import as video; if you export two seconds of video as a filmstrip file, you’ll get two seconds of video when you re-import it, not 50 still image files. Filmstrip files are useful if you want to apply the same effect, for example a special effects filter, to every frame in the sequence.

Alternatively, you can export a sequence of frames from Premiere Elements 2.0. Select Movie from the File>Export menu and click the Settings button in the Export Movie dialogue box.

Then, in the General panel of the Export movie settings dialogue, select a still image format such as Jpeg or Tiff from the File Type pulldown menu. As with other movie exports, choosing ‘Work Area Bar’ using the Range pulldown menu allows you to confine the export to a range of frames rather than the entire timeline.

Premiere Elements saves the frames as individual, sequentially numbered files, which you can open in any image editor. Once you’ve got this far the potential for special effects increases by several orders of magnitude over what’s available in most video editors. Most video editors lack sophisticated colour controls, but that is not true of photo editors.

Something as simple as adding an effects filter can produce spectacular results. Photoshop Elements’ Sketch filters, such as Chalk and Charcoal, Water Paper and Graphic pen, produce good rotoscope-style animated looks. Experimenting with image adjustment controls, reducing saturation or posterizing frames can also be effective ways of achieving rotoscope-style effects with the minimum of effort.