| 摘要 |
PROBLEM TO BE SOLVED: To provide a video display device that automatically processes a black level to have a 0 IRE level (pedestal level) when the black level of a video signal is set up to other level. SOLUTION: A pedestal clamp section 1 clamps a video signal at a pedestal level, an analog/digital converter section 2 converts the video signal into a digital signal, and a comparison section 4 compares the black level for a video display period with a reference value read from a storage section 3. When the black level is higher than the reference value, the comparison section 3 outputs a signal denoting presence of setup, and an arithmetic section 5 receiving this signal subtracts a prescribed value (a value equivalent to the reference value) from the video signal outputted from the analog/digital converter section 2. A changeover section 6 selects the output of the arithmetic section from the output of the analog/digital converter section depending on the signal denoting the presence of setup received from the comparison section 4.
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