| 摘要 |
PROBLEM TO BE SOLVED: To obtain a variable bit rate coder by obtaining a subject evaluation value corresponding to a coding bit rate, conducting prescribed processing based thereon, and coding optimizingly the entire image quality while keeping the average bit rate to be a prescribed value. SOLUTION: A variable bit rate coding section 2 encodes digital image data 1 for a prescribed time length for each variable bit rate so that the average bit rate is a specified value or below. A subject evaluation section 4 obtains a subject evaluation value corresponding to the different coding bit rate for each unit time being division of the digital image data 1 for a prescribed time. A bit rate allocation section 5 decides the bit rate for each unit so that the average bit rate is an object rate or below based on the obtained subject evaluation value and the desired evaluation of the entire image quality is optimum. Thus, optimum bit rate arrangement is attained with respect to image data in each unit time under a prescribed condition. |
