Digital television data compression system

Claim 1

IN A TELEVISION SYSTEM FOR SUBJECT REPRESENTATIVE DIGITAL SIGNALS IN WHICH THE BRIGHTNESS VALUES OF THE ELEMENTAL SUBJECT AREAS ARE REPRESENTED RESPECTIVELY BY A CODE OF N DIGITS OF WHICH THE FIRST N/2 DIGITS CONSTITUTE A COARSE WORD SIGNIFYING ONE OF K COARSE BRIGHTNESS VALUSES OF SAID SUBJECT AND THE LAST N/2 DIGITS CONSTITUTE A FINE WORD SIGNIFYING ONE K FINE BRIGHTNESS VALUES OF SAID SUBJECT WITHIN ANY ONE OF SAID COARSE BRIGHTNESS VALUES, THE COMBINATION COMPRISING: MEANS FOR SEQUENTIALLY TRANSMITTING A FIRST PREDETERMINED NUMBER OF SAID COARSE WORDS REPRESENTING A FIRST COARSE BRIGHTNESS VALUE OF SAID SUBJECT; MEANS FOR DISCONTINUING SAID COARSE WORD TRANSMISSION IN RESPONSE TO A DETERMINATION THAT SAID FIRST COARSE PICTURE BRIGHTNESS VALUE IS REPRESENTED BY AT LEAST A SECOND PREDETERMINED NUMBER GREATER THAN SAID FIRST PREDETERMINED NUMBER OF SAID COARSE WORDS; MEANS FOLLOWING SAID COARSE WORD TRANSMISSION DISCONTINUATION FOR SEQUENTIALLY TRANSMITTING ONE OR MORE OF SAID FINE WORDS REPRESENTING FINE BRIGHTNESS VALUES OF SAID SUBJECT WITHIN SAID FIRST COARSE BRIGHTNESS VALUE; MEANS RESPONSIVE TO A DETERMINATION THAT AT LEAST ONE OTHER COARSE WORD IS PRODUCED REPRESENTING A SECOND COARSE BRIGHTNESS VALUE OF SAID SUBJECT FOR DISCONTINUING SAID FINE WORD TRANSMISSION AND REVERTING TO SAID COARSE WORD TRANSMISSION; MEANS FOR SEQUENTIALLY RECEIVING BOTH OF SAID COARSE AND FINE WORDS; AND MEANS HAVING COARSE AND FINE WORD OPERATING MODES RESPECTIVELY, FOR PROCESSING SAID SEQUENTIALLY RECEIVED COARSE AND FINE WORDS OF N/2 DIGITS SO AS PRODUCE SIGNALS HAVING N DIGITS AND COMPRISING COMBINATIONS OF SAID COARSE AND FINE WORDS OF N/2 DIGITS.