Processing in Variable Speed Playback of a VTR.
Hitoaki Owashi, Kyoichi Hosokawa, Kazuhiko Yoshizawa, 美代子 吉越, Toshiaki Takahashi · The Journal of The Institute of Image Information and Television Engineers · 1992
In variable speed playback of a composite video tape recorder (VTR) , the reproduced video must be converted to a standard TV signal because fields in the reproduced video are skipped or repeated .For field conversion processing, a Y/C separation circuit and a line-interpolation circuit are used .In a conventional processor, the picture quality deteriorates due to vertical displacement of the image and lower resolution.Our new motion-adaptive field-conversion circuit that uses inter-field signals can remove these deficiencies.The focus of this paper is on a motion-adaptive line-interpolation technique .It also describes a new line-interpolation filter with a motion detection function that compares the amplitude of inter-field signals.Based on these techniques, three kinds of gate arrays were developed .The arrays were employed in D-2 VTR for NTSC signals.This VTR exhibits none of the problems mentioned above and has picture quality comparable to that at standard play-back speed.1.