PVC by Chris and Trish Meyer
Ever pulled your own hair out trying to key or rotoscope hair or other soft edge details? Help is on the way.
Earlier today, Adobe posted a video called The History (and Future) of Rotoscoping in After Effects. It gives a quick overview of how masking has evolved over the years in AE, as well as Paint and Roto Brush. At the very end, it teases a new technology called Refine Edge that seems to magically create a detailed alpha channel around the hair of a dancing girl. Adobe has given me the chance to work a bit with Refine Edge, and invited me to share my initial thoughts with fellow users. (Just so we’re clear up front, I’m receiving no compensation from Adobe for this; these are my honest reactions and advice after using it.)
Refine Edge is primarily an extension onto Roto Brush, which was initially released in After Effects CS5. For those who haven’t mastered it yet, Roto Brush allows you to make a series of general paint strokes defining the foreground and background areas of an image (such as an actor over a complex background - in other words, not greenscreen). With this information - as well as judicious tweaking of its propagation parameters - Roto Brush then detects the edge between the foreground and background, and creates a matte. When used properly, it can greatly reduce the labor involved in cutting elements out of video.
However, an issue with Roto Brush is that at its core, it creates a “binary” matte - you were either foreground or you were background, without a broad or detailed gray area in between. It does have automatic motion blur and edge color decontamination, which works fine on hard-edged shapes like in-focus shirt sleeves, but does introduce compromises for areas with detailed or partial transparency such as wispy hair, out-of-focus edges, exaggerated motion blur, etc.
Roto Brush & Refine Edge
As noted above, Refine Edge will be an extension to Roto Brush, as shown in the Effect Controls panel here. After the Roto Brush module has been used to create a good binary matte, the Refine Edge module then goes after those nuanced areas of partial transparency - such as fine, wispy hair. Using the same brush stroke paradigm as Roto Brush, you create Refine Edge brush strokes to indicate where the areas of partial transparency are, as well as help define tricky areas that should be fully transparent or opaque. These refine strokes track along with the matte edge created by Roto Brush, greatly reducing the number of corrective strokes you need to make. read more...