| 摘要 |
<p>PURPOSE:To obtain a video signal converter having a simple composition and free of deterioration in picture quality. CONSTITUTION:Video signal Sy which forms a picture by performing scanning in the circumferential direction and scanning in the radial direction, is supplied to random access memory 12. At the same time, synchronizing signal Sa for scanning in the circumferential direction is supplied to the prescribed multiplying circuit 31, and this multiplying signal is supplied to counters 32 and 37, to form a signal that corresponds to the angle of scanning in the circumferential direction. This angle signal is supplied to operational circuit 33 which calculates sin theta and to operational circuit 34 which calculates cos theta. Signals from these operational circuits are supplied to multiplier circuits 41 and 42 respectively, Further the said signal Sr is supplied to the prescribed multiplying circuit 21, and the signal from 21 is supplied to counter 22, thereby forming a signal which corresponds to the length of scanning in the said radial direction. This signal is then supplied to multiplier circuits 41 and 42, thereby forming address signals in the horizontal and vertical directions that correspond to the scanning position in the said circumferential direction and to the said scanning position in the radial direction. These signals are supplied to memory 12 and stored, and the video signal is read out by scanning memory 12 in the horizontal and vertical directions.</p> |
