Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media.[1] Video was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) systems, which, in turn, were replaced by flat-panel displays of several types.
Video systems vary in display resolution, aspect ratio, refresh rate, color capabilities, and other qualities. Analog and digital variants exist and can be carried on a variety of media, including radio broadcasts, magnetic tape, optical discs, computer files, and network streaming.
Video was invented decades after film, which records a sequence of miniature images visible to the eye when the film is physically examined. Video, by contrast, encodes images with electromagnetic waves.[3]
Video technology was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) television systems. Video was originally exclusively live technology. Charles Ginsburg led an Ampex research team to develop one of the first practical video tape recorders (VTR). In 1951, the first VTR captured live images from television cameras by writing the camera's electrical signal onto magnetic videotape.
Video recorders were sold for US$50,000 in 1956, and videotapes cost US$300 per one-hour reel.[4] However, prices gradually dropped over the years; in 1971, Sony began selling videocassette recorder (VCR) decks and tapes into the consumer market.[5]
Digital video is capable of higher quality and, eventually, a much lower cost than earlier analog technology. After the invention of the DVD in 1997 and later the Blu-ray Disc in 2006, sales of videotape and recording equipment plummeted. Advances in computer technology allow even inexpensive personal computers and smartphones to capture, store, edit, and transmit digital video, further reducing the cost of video production and allowing program-makers and broadcasters to move to tapeless production. The advent of digital broadcasting and the subsequent digital television transition are in the process of relegating analog video to the status of a legacy technology in most parts of the world. The development of high-resolution video cameras with improved dynamic range and color gamuts, along with the introduction of high-dynamic-range digital intermediate data formats with improved color depth, has caused digital video technology to converge with film technology. Since 2013,[update] the use of digital cameras in Hollywood has surpassed the use of film cameras.[6]