Abstract: To decrease the computational complexity and improve the image quality，a novel rate control algorithm is proposed.Target bits are allocated for each frame according to the image complexity during the encoding procedure.The variance of pixels is calculated for basic unit to represent the texture complexity.Bit allocation is optimized according to the texture complexity.Experimental results show that the proposed algorithm achieves a bit rate closer to the target while keeping PSNR almost unchanged.

Key words: rate control, variance of pixels, texture complexity

摘要： 为降低计算复杂度，提高图像质量，提出了一种新的码率控制算法。编码过程中根据图像内容的自适应性和图像复杂度分配帧层的目标比特数，在基本单元层通过计算当前基本单元的亮度像素方差，来衡量该区域的纹理复杂程度，通过纹理复杂度优化比特分配。实验结果表明：与原算法相比，该算法在几乎不影响信噪比的情况下，能将码率更精确地控制在目标码率附近。

关键词: 码率控制, 像素方差, 纹理复杂度