TV Broadcasting in 3D
The promise of 3D TV broadcasting revolves around a stunningly realistic display that provides the element of depth to the viewing experience. Although the concept of three dimensional video is not new, recent advancements in the technology have made the format far more appealing on a mass scale.
Three dimensional presentation was developed in 1838 by Charles Wheatstone, a British researcher who discovered that two images projected from slightly different perspectives could be fused into a single three dimensional representation. Various attempts to capitalize
on the new technology were largely unsuccessful, but ambitious projects like the 1922 full length feature film, “The Power of Love,” demonstrated that the three dimensional effect could find a wide audience.
It wasn’t until the 1950’s when movie studios were threatened by the explosive popularity of television that 3D was reintroduced into films. A rash of low and medium budget projects were introduced that included three dimensional viewing by implementing the anaglyphic process. This included specialized cameras, projection equipment and viewing glasses that were distinguished by the familiar red and blue lenses.
Unfortunately analog 3D faded quickly as movies were poorly shot and projectors were often misaligned or malfunctioned. These conditions lead to extreme eyestrain and a generally unsatisfactory viewing experience. Within a year, 3D once again disappeared, only frequently reemerging through the late 20th century.
Current 3D Broadcasting Standards
Recent enhancements in 3D TV broadcasting technology has resulted in a major cooperative initiative between broadcasters and audio visual equipment manufacturers. The impediment to seamless 3D broadcasting revolves around the challenge of fitting the 3D data stream into the existing bandwidth used for 2D hi definition.
The three current methods for delivering 3D all involve a compression scheme called, “compatible spatial compression.” This methodology involves separating pixels into left and right frame images and frame packing which determines the organization of the right and left images when they are transmitted and reassembled.
Whatever format is used, it is important to select a television that has the capability to decode the data so that both images are displayed in a manner that reconstructs the pixels for proper interpretation by the eyes and brain.
Modern 3D glasses employ shutter technology which blocks certain images from reaching your eyes. Older polarized glasses only filtered out the images and this was a source of eye fatigue, headaches and irritation. Shutter glasses communicate with an IR transmitter that sends signals to the glasses to control the blocking of images at a very fast refresh rate. These glasses are operationally active and need their own power source.
The Future of 3 D Broadcasting
Early in 2010, the first commercial 3D broadcast of a hockey game between the New York Rangers and the New York Islanders featured the latest technology and compression protocols. The success of this and subsequent broadcasts prompted equipment manufacturers and broadcasters to speed up their efforts to bring 3D to the general market in a meaningful way.
HDMI Licensing is the entity that supports high definition multimedia interface networking technology. They provide industry standardization for the connection protocols that include digital TV sets, cable and satellite boxes and Blu-ray players. In the new HDMI specification 1.4, vendors are provided with the information they need to create 3D broadcasts for 3D compatible HDTV displays.
Future developments include television sets that can display a 3D picture without the need for special glasses. In fact, this is the advancement that may trigger mass appeal of 3D TV broadcasting. By implementing existing lenticular lens technology, separate images can be magnified and combined to give a 3D effect without eyewear accessories.
Whatever the technology that ultimately prevails, the massive investment into 3D hardware and broadcasting infrastructure virtually ensures that this incarnation of 3D visuals will be more than just a passing fad.
Image credit: flickr.com