| 摘要 |
<p>PURPOSE:To eliminate distortion attended with resolution conversion of an interlace picture comprising even and odd number fields. CONSTITUTION:An interlace picture is separated into even odd number fields by a field separator 25 included in an encoder 11, the fields are subject to orthogonal transformation at N point DCT 21-1, 21-2 and the result is sent to a decoder 62. Phase shift is applied at an M point PS-IDCT 80 included in the decoder and the result is inversely transformed and no phase shift is applied at an M point IDCT 71 and inverse transformation is applied and in the case of M<N, resolution conversion by M/N is applied and a synthesis output is obtained at a field synthesizer 75. Since distortion caused by phase shift attended with the resolution conversion is eliminated, the picture quality of a decoded picture is improved.</p> |
