Originally featured on BroadcastEngineering.com
Cel-Soft develops automated edge-violation indicators for 3-D analyzer
Cel-Soft (www.cel-soft.com) has announced automatic detection of edge-violation, a new addition to the feature set of its Cel-Scope3D stereoscopic signal analyzer.
Edge violation is a visual artifact that can arise when part of an object is visible at the edge of one image pair but not at the other. The brain normally compensates for edge violation when viewing the real world, as it does with many other inherent defects of human visual perception. Viewing through a television or cinema frame, however, it can become confused.
Edge violation can be fixed in post production but is best handled when producers are alerted to the problem during the initial shoot. Spotting where edge violations are occurring takes a practiced eye as they may not be obvious.
Using the latest version of Cel-Scope3D, edge violation can be displayed automatically in several ways. Alarm messages can be superimposed on the analyzer's display screen as soon as the violations are detected. Additionally, the offending objects are visually highlighted yellow on the depth map display. With the logging option, edge violations can be automatically logged with time code in a report along with over 30 user-settable parameters and checks.
A cost-effective system for 3-D signal monitoring, Cel-Scope3D 1.4 can analyze file-based content as well as live or recorded signals in dual-stream or multiplexed formats. It allows stereoscopic camera alignment to be performed quickly and confidently, ensuring the 3-D synchronization is accurate from the moment of capture. Footage and edits in a wide range of file formats can be viewed and assessed in real time.
An example of edge-violation can be seen in the accompanying diagram pair, which shows a street lamp located on the extreme left in the foreground. With the cameras converging on the middle ground, only the right-hand camera is able to display the entire lamp post.
Viewed in 2-D the supporting pillar is only partly onscreen. The rest of the pillar is perceived as being behind the frame. If the shot is viewed in 3-D and the post is in front of the screen plane, then some of it appears to be levitating. This conflict can causes eyestrain, headaches or even nausea.