01530nas a2200205   4500008004100000245006400041210006100105260000900166300001400175490000600189520088400195653001901079653001001098653001701108653003301125100001601158700001601174700001701190856011701207       2008                        eng d00aOptimal two-pass frame-layer bit allocation for H.264 Video0 aOptimal twopass framelayer bit allocation for H264 Video  c2008  a174 - 1790 v63 aIn this work, the frame-layer bit allocation problem is studied for H.264 video. We first impose a GOP (Group of Pictures) structure on the underlying H.264 video, and then develop a two-pass rate control algorithm based on the Lagrange optimization framework. The proposed algorithm estimates the rates and the distortions of all frames in a GOP by preencoding them using a constant quantization parameter (QP) in the first pass. The target number of bits of each frame is determined by searching the Lagrange multiplier that meets the bit budget constraint for the GOP. The proposed algorithm is useful for nonconversational applications such as video streaming where video sources can be encoded off-line. Experimental results demonstrate that the proposed algorithm achieves substantially higher picture quality than the rate control algorithm in the H.264 reference encoder.10aBit allocation10aH.26410aRate control10aRate-distortion optimization1 aKwon, D.-K.1 aShen, M.-Y.1 aKuo, C.-C.J.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-72449209699&partnerID=40&md5=c41f97ca2d0ee3770b908360518c355601882nas a2200205   4500008004100000245010400041210006900145260000900214300001400223490000600237520116000243653002401403653003401427653003101461653001401492653001701506100001901523700001701542856011701559       2008                        eng d00aRate control scheme based on cauchy R-D optimization model for H.264/AVC under low delay constraint0 aRate control scheme based on cauchy RD optimization model for H2  c2008  a180 - 1880 v63 aThe motivation of this work is based on the observation that Cauchy distribution provides more accurate estimates of rate and distortion characteristics of video sequences than the previously used distribution such as Laplacian distribution. In this paper, we propose a new rate control scheme for H.264 low-delay video transmission using Cauchy rate-distortion optimization model. Our proposed method uses the Lagrange Multiplier technique to optimize the cost function, and be able to find the rate and distortion model subject to the target bit rate constraint resulting in the optimum choice of quantization step sizes. Model parameters are estimated using statistical linear regression analysis. The target number of bits for each frame is determined according to their buffer status, the number of bits use in the previous frame, and basic unit complexity. The proposed scheme has been implemented on H.264 video coder. Simulation results show that the proposed rate control algorithm achieves, on the average, an improvement in PSNR for up to 1.68dB with lesser number of frames skipped as compared with the default H.264 JM8.6 rate control scheme.10aCauchy distribution10aLagrange multiplier technique10aLinear regression analysis10aLow delay10aRate control1 aEiamjumrus, N.1 aAramvith, S.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-72449205119&partnerID=40&md5=60340eb5bbe6774b89e2d6c72f1c7181