MULTIPLE CODER AND DECODER

PURPOSE:To attain rational data amt. distribution to plural images by controlling coding quantity generated from plural coding systems by the degree of sufficiency of a data buffer added after multiplexing data. CONSTITUTION:A multiplexer 10 multiplexes the data of images (a), (b) and quantizing information outputted from a quantization controller 5 as a compressed data string. The multiplexed data are applied to the data buffer 11, which absorbs variation in the rate of image data and outputs the multiplexed data with a fixed rate from a data output 12 to a decoder. On the other hand, information indicating the degree of sufficiency of the buffer 11 is applied to the controller 5 and quantizing information determined by the controller 5 is applied to quantizers 3, 8. Although convensional quantizing information controls the quantizers so that data amount of both the quantizers are equal to each other, this quantizing information controls the quantizers so that quantizing steps are equal to each other.