FRAME-BASED AUDIO CODING WITH VIDEO/AUDIO DATA SYNCHRONIZATION BY DYNAMIC AUDIO FRAME ALIGNMENT

摘要

Several audio signal processing techniques may be used in various combinationsto improve the quality of audio represented by aninformation stream formed by splice editing two or more other informationstreams. The techniques are particularly useful in applicationsthat bundle audio information with video information. In one technique, gain-control words conveyed with the audio information streamare used to interpolate playback sound levels across a splice. In anothertechnique, special filterbanks or forms of TDAC transforms areused to suppress abasing artifacts on either side of a splice. In yet anothertechnique, special filterbanks or crossfade window functions areused to optimize the attenuation of spectral splatter created at a splice. Ina further technique, audio sample rates are converted accordingto frame lengths and rates to allow audio information to be bundled with, forexample, video information. In yet a further technique, audioblocks are dynamically aligned so that proper synchronization can bemaintained across a splice. An example for 48 kHz audio with NTSCvideo is discussed.