| 摘要 |
Apparatus for directly recording television signals on a magnetic medium strips out sync and blanking information. Low frequency components of the television signals are time compressed, i.e. frequency shifted, and recorded as a substitute for the stripped-out sync and blanking information. Thus, high frequency components of each video line are recorded, followed by that line's low frequency components, thereby facilitating the playback of low frequency information. In time compressing the low frequency information, the video signal content of a line is sampled at a predetermined rate. Each sample is then quantized for purposes of improving the playback signal-to-noise ratio, i.e. the effect of tape modulation, and other, noise is nullified by sample quantization. And, to cut the bit rate resulting from sample quantization, a preferred form of the invention groups the quantized bits and records analog representations of the bit groups.
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