The geometric differences between left and right images are known as a main factor of eye fatigue in the stereoscopic system. We developed a real-time stereoscopic error corrector which can adjust the vertical errors, the disparity, and the size (field of view) errors of HD moving pictures in VCR tape. The main idea of this system is to extract and use only the common area of both images by cropping the left and right images independently. For this system, we developed a realtime HD scaling hardware and stereoscopic error correcting software. We tested the system with the video streams taken by our HD stereoscopic camera. As a result, we confirmed that the developed system could reduce the efforts and time for correcting the stereoscopic errors compared to the other methods. We also developed a real-time zoom-convergence interlocked controller for HD parallel-axis stereoscopic camera using the same hardware. Because it doesn't need motors for parallax move, we could control the convergence more smoothly while locking it with zoom.