摘要 |
Surround stereo signals are synthesized from the composite or DME monaural sound tracks of audiovisual programs by use of multi-channel, computer-controlled digital circuitry and operator-programmed sound cues, the latter matching video time codes with audio control signals. The stereo signals have out-of-phase delay components, resulting in compatibility with conventional monaural audio equipment, and steerable pan components, resulting in selective sound placement capability. Variable time delays and variable ratios of dry and delay are used in conjunction with panning movements to achieve a wide variety of acoustical effects, such as resonance, spread and cutting, which correlate the audio portion of the program with the video portion of the program. An operator selects and programs sound cues and stores them for playback by using a plurality of audio controls and a computer interface which are provided on an operator console. Subroutines are used for automated cue recording and for editing. Stereo sound tracks are created from monaural source material. |