Improvement of Picture Quality in Nonstandard Speed Play of Digital VTR
Hitoaki Owashi, Kyoichi Hosokawa, Kazuhiko Yoshizawa, Yoshizumi Watatani, Shoji Ohno, Toshiaki Kawamura · 1992
In nonstandard speed play of a composite video tape recorder (VTR), the reproduced video is converted to a standard TV signal, since fields in the reproduced video are skipped or repeated. For the field conversion processing a Y/C separation circuit and a line-interpolation circuit are used. In a conventional processor, the picture quality is deteriorated due to vertical displacement of the image and lower resolution. To remove these deficiencies a motion-adaptive field-conversion circuit, which uses inter-field signals, has been developed. Based on these techniques, three kinds of gate arrays were developed and employed in a D2 VTR for NTSC signals. Consequently above problems were solved and picture quality was remarkably improved.