| 摘要 |
PURPOSE:To obtain a video signal processing device which can use effectively the number of quantizing steps of an A/D converter by digitizing the signal part only excluding a synchronizing signal when an analog video signal is digitized. CONSTITUTION:An analog video signal 100 inputted from an input terminal 501 goes to be a signal 101 while it is clamped at a clamping circuit 2. Here, the circuit 2 fixes the direct current level of the signal so as to code a pedestal level to ''0001'' and a white 100% level to ''1111'' by an A/D converter 3. As the result, to the dynamic range of the converter 3 only the video information part excluding the synchronizing signal is assigned. A signal 102 A/D-converted by the converter 3 is guided to a synchronizing signal coding circuit 5, and the signal of ''0000'' is clipped to ''0001'' by a clipping circuit 6 in the circuit 5. Further, for the signal 103 in a synchronizing adding circuit 7, the synchronizing signal part is coded to ''0000'' and a signal 105 is obtained by matching with the timing of a synchronizing signal 104 separated by a synchronizing separating circuit 4.
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