Estimating the value of θ in the intra frame for ρ-domain rate control algorithms
The ρ-domain rate control algorithm is very simple and effective. There is only one parameter, θ, used in the model. θ reflects the relationship between the rate and the quantization step. Accurately estimating the θ value of the I (intra) frame is important for an efficient ρ-domain rate control algorithm because the I frame will influence the remaining frames in the GOP (group of pictures) greatly. In this paper, we propose to estimate the θ value based on the energy of the frame. The energy difference of the I frames is used to predict the new θ. A linear relationship between θ and the energy is deduced. Experimental results show that using the energy can more accurately predict the θ value of I frame than only using the θ value of the previous P (predict) frame.