New bit-rate control models for image and video transmission

This paper presents two new schemes of bit rate control: a linear significant coefficient percentage model and a mixed power function model of step-size. Based on the rate-distortion characteristics of wavelet images, the relationship between the percentage of significant coefficients and the output bit-rate is examined, and a linear model is developed. Next, a mixed power function model is introduced as the regression of experimental results. Both bit rate control algorithms have been implemented for the X-tree wavelet coder. Simulation results have verified the effectiveness of the new bit-rate control models.