Abstract: An algorithm of improved reduced spatial resolution video transcoding is proposed in this paper. An adaptive intra-refresh scheme is presented based on the relation between drift error and motion activity of inter-coded blocks. The thresholds are dynamically adjusted according to the difference between the target bit rate and actual bit rate. This method can reduce the bit rate of intra coded frames while still maintating error robustness and limiting temporal propagation of errors. Besides, a linear rate control strategy is also present. In order to reduce computational complexity, the rate-distortion function can be mapped into a linear function. The simulation results show that the buffer fullness tend to be stabilized and the PSNR of the reconstructed image is raised.