Patent ID: 7714751
Filing Date: 2010-05-11
Classification: H04N

Abstract:
1. A transcoder for converting a first stream into a second stream, comprising: a part for acquiring a bit rate of a whole first stream; a part for setting a target bit rate of a whole second stream; a part for calculating a reference conversion factor on the basis of a ratio between said target bit rate of said whole second stream and said bit rate of said whole first stream; a variation coefficient calculation part for calculating a coefficient of variation from said target bit rate of said whole second stream and a bit rate of a second stream converted before a N period; a part for calculating a period conversion factor in a next (N+1) period by adding said coefficient of variation to said reference conversion factor; and a part for calculating a quantization step value of a second stream in the (N+1) period by multiplying a quantization step value of a first stream in the (N+1) period by said period conversion factor.