| 摘要 |
A frame of time-domain video signals Si is supplied via a frame reorderer (40) to a motion vector estimator (41), and then to a DCT transformer (43) and a quantizer (44) to produce a quantized, transformed current frame STi/q. A subtracter (42) subtracts a transformed quantized prediction frame STp/q from STi/q to produce an inter-encoded signal DELTA . The prediction frame STp/q is produced by adding the prediction signal to STp/q to the inter-encoded signal DELTA , dequantizing (46) and inverse transforming (47) the sum and applying the sum to a motion compensation circuit (49) to produce a time domain prediction signal Sp which is transformed (50) and quantized (51) to produce STp/q The quantizers (44) and (51) are controlled by the same quantization level Qv. The encoder and a corresponding decoder allow frames to be encoded and decoded with reduced reconstruction errors in systems where compress ion codecs are cascaded. |
