IMAGE ENCODING METHOD AND DEVICE AND IMAGE RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To encode the images at the optimum encoding rate in response to complexity and especially the contrasts of the images and also to reflect the human visual characteristic on the image encoding. SOLUTION: A 1st encoding circuit 10 applies the predicted encoding, DCT conversion, quantization and variable length coding processing to the input image signals. A luminance signal mean value calculation circuit 60 calculates the mean value at every prescribed time for luminance signals of input video signals and sends the mean value to an encoding control circuit 30. The circuit 30 calculates the encoding rate at every prescribed time based on the code value of the encoded data on the circuit 10 generated at every prescribed time, the image characteristic information given from the circuit 60 and also the total available data quantity. A 2nd encoding circuit 40 encodes the input video signals at every prescribed time based on the calculated encoding rate and generates the 2nd encoding data.