BIT RATE CONVERSION APPARATUS FOR ENCODED MOVING PICTURE DATA

摘要

PROBLEM TO BE SOLVED: To convert a bit rate of moving picture data at a high speed and a low cost without the need for complicated processes such as decoding and reencoding of the moving picture data up to an image area while minimizing visual deterioration in the moving picture data after the conversion. SOLUTION: A picture type discrimination section 12 discriminates whether an input frame is a reference frame or a non-reference frame, inputs DCT coefficient information COEF2 from a dequantization section 1 to a DCT coefficient adder section 3 or a requantization section 4 depending on the result of discrimination, wherein bit rate conversion is performed by adaptively using re-quantization with compensating a quantization error or simple requantization. Or the requantization with compensating a quantization error or simple requantization is selected in the unit of macro blocks for performing bit rate conversion. COPYRIGHT: (C)2003,JPO