Video
Synchronization techniques differ yet again when considering video postproduction. in that the technology used is electronic rather than mechanical, as is the case with film. Video postproduction began around 1956, following the development of the first videotape machine. Videotape benefited both television and film composers in its versatility. All television programmes were previously recorded live. so had to rely on whatever sound effects or music that could be created in the studio. The advent of videotape meant that producers could both add sound effects and music as required. and edit programmes to achieve a smoother, more professional effect.
Videotape's main advantage is that it is an electronic medium. and is therefore easily manipulated by computers. This saves on the large labour costs that are often associated with film editing and postproduction. Preparing a picture (stream and punch and calculating various click starts) for a scoring session for a one-hour television programme being done on film may take a music editor six to eight hours. The same show, done on videotape and using the " VideoScore" system (a computer program designed by The 'Music Design Group editing company) would probably take no more than 30 minutes.
The technology available to aid video post-production was developed by a number of different companies. co-operating over several years to create a network of services that were technologically compatible. The Neiman-Tiller Associates developed the ACCESS system in the mid-1970s - a video-based sound effects digital editor, but the "PAP" system, developed around the same time by Glen Glenn Sound became the main system used.
The Music Design Group pursued the development of music editing techniques at a time when most companies were concerned with sound effects, dialogue replacement and mixing etc. The systems developed by the Music Design Group fall into two areas:
- pre-scoring and scoring
- assembling of tracks for the dubbing session.
The sound for videotape is recorded onto audio recording tape (either two-inch 24 track or half-inch 4 track tape depending on the number of tracks needed). Sound and image are synchronized by use of the SMPTE time-code. This was developed by the Society of Motion Picture and Television Engineers and is a standardized timecode. SMPTE is a set of numbers, consisting of hours, minutes, seconds and frames (video runs at 30 frames per second as opposed to film's 24) which can be laid down onto tape as an audio signal or an image. A timecode number may read 02:01:38:27 when read left to right would mean that our position in the duration of the film would be two hours, one minute, 38 seconds and 27 frames.
SMPTE's audio signal is used to link up different audio equipment, the timecode being standard to them all. These different machines may play music, or sound effects etc. and they work by following the timecode of the videotape machine and their audio tracks move in synchronization with the image, the audio tracks being read by synchronizers such as "Q-Lock" or "LYNX" devices.
As with film, breakdown notes have to made, so The Music Design Group developed a computer-based system known as VideoScore which did this work digitally. The main advantage of this system is that any changes made to the length of the music cues by the director extending or cutting scenes, means that the music editor does not have to recalculate the entire set of breakdown notes.
SMPTE is used again at the dubbing stage. The soundtrack is recorded with identical timecode to the one on the picture, and then synchronized with the other audio elements, such as sound effects. The most common use of audio tape so far has been the 4-track. but the advent of stereo television and Dolby SurroundSound will probably lead to to a demand for more audio tracks. This is the next stage for the synchronization of sound and image.
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