| 摘要 |
1362191 Television standards conversion INDEPENDENT BROADCASTING AUTHORITY 22 June 1971 [26 March 1970] 14976/70 Heading H4F A television line standard converter uses an interpolation control 401 to set four gain controls 402, 427, 453, 478 receiving signals from four consecutive lines, the resulting signals being added in an adder 444. For 625 to 405 line conversion the adder 444 provides 625 lines, 405 lines containing information and 220 being blank. Only the information carrying lines are written into stores 12, 15, 18, in sequence, the stores then being read at the line rate of 405 line output, the correct sync. signals being added in processor 115. The received signals may be converted to binary form at 207, reconversion to analogue form being carried out before application of the signals to processor 115. The binary signals may be processed in three channels, each channel operating at onethird the required total rate. Chrominance signals may also be converted to digital form as digital (R-Y) and (B-Y) signals and processed. The delay lines 3, 6, 9 and stores 12, 15, 18 may use shift registers. The 220 blank lines may alternatively be written into stores 12, 15, 18, these lines being omitted in the reading process. For 405 to 625 line conversion, 220 additional lines are supplied to stores 12, 15, 18 via an additional interpolator and set of gain controls. |
