| 摘要 |
<p>A method for enabling an increase in the vertical definition of a transmitted television signal while preserving its bandwidth including the steps of decimating alternate lines of the television signal and reinterpolating untransmitted alternate lines upon reception. The decimation is accomplished by diagonally filtering the televison signal in two dimensions to form a figure of five sample structure. Every other line is then added to the line adjacent to it so that half the lines are available for transmission, each line comprising folded-in high frequency information about missing line samples. Prior to transmission, bandwidth is conserved by filtering the signal to be transmitted at a skew-symmetric low pass filter. Apparatus for encoding and decoding the television signal each includes a two dimensional diagonal filter and line switching and control circuitry. The storage of a full field of sample data is not required for processing in accordance with the present method. Consequently the present apparatus comprises only line store means associated with the line switching and control circuitry of encoding apparatus.</p> |
