Method and apparatus for providing scaleable compressed video signal

摘要

A compression/decompression system includes a source of non-interlaced scanned video signal. A preprocessor constructs interlaced scanned video signal from the non-interlaced scanned video signal by selection of alternate lines of successive non-interlaced image signals. The interlaced scanned video signal is compressed according to known methods to generate primary compressed video data. The primary data is decompressed by known processes, inverse to the compression processes, to regenerate the interlaced scanned frames. Interlaced scanned video signal, corresponding to the intervening lines of the non-interlaced scanned video signal, which were not included in the primary interlaced scanned video signal, is predicted from the decompressed frames of video signal. In addition the intervening lines of the original non-interlaced scanned video signal, which were not included in the primary interlaced scanned video signal, are formed into secondary interlaced scanned video signal. The secondary video signal is subtracted from the predicted video signal to generate secondary field residues. These residues are compressed by known methods to form compressed secondary video data. The primary and secondary compressed data are thereafter transmitted for reception by either interlaced scanned receivers or non-interlaced scanned receivers.