Image data coding and decoding method and apparatus with a plurality of

Abstract

An image data coding device includes a plurality of orthogonal transform circuits for subjecting a plurality of image data items divided into blocks to the orthogonal transform. A plurality of quantization circuits quantize the orthogonal transform outputs supplied from the plurality of orthogonal transform circuits for each frequency component. A plurality of variable length coding circuits subjects the quantized outputs supplied from the plurality of quantization circuits to the variable length coding process. A plurality of memory circuits store outputs of the plurality of variable length coding circuits in a bit-series configuration. An output circuit reads out bit-series data items stored in the plurality of memory circuits by turns, connecting the readout data items together and outputting the data for each byte.