| 摘要 |
An arrangement for digitizing television signals, particularly the staircase portion of the vertical interval test signal transmitted by the British Broadcasting Corporation and the Independent Broadcasting Authority comprises a luminance/chrominance separator (2) and two analog to digital converters (ADC's) (6, 9). The ADC(6) digitizes the color subcarrier which has a low amplitude but a high frequency while the ADC(9) digitizes the high amplitude low frequency luminance portion. The digitized samples are stored in two sections of RAM (11, 13) under the control of a write address generator (25) and two respective write control circuits (14,17). The ADC(6) operates at 4fsc and has a resolution of 7 bits while the ADC(9) operates at one sixteenth of that rate and has a resolution of 10 bits. This enables a full 10 bit resolution to be obtained without requiring a high cost ADC.
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