A Novel Square Root Rate Control Algorithm for H.264/AVC Encoding

Though rate control is not normalized in any video coding standards, it plays an important role in video coding/communication area. Rate control algorithms aim to achieve perceivable video quality in video communication applications under some real-world constraints, such as bandwidth, delay, buffer sizes, etc. This paper presents a novel rate control mechanism for low delay video communication of H.264/AVC standard at basic unit level. In order to realize rate control through various quantization parameters Q, an accurate square root model between bit rate and Q is established through rho-domain rate control theory When compared with the rate control scheme JVT-G012 [1] which is adopted by the JVT H.264/AVC reference software JM12.3[2], the proposed rate control algorithm could not only reduce the mismatch between actual bit rates and target ones, but also increase the average luminance PSNR of reconstructed video for around 0.1-0.2 dB at low bit rates.