Research Of H.264 Rate Control Algorithm And Realization On Davinci Platform

Performance of H.264, which was the latest global video code standard, could be describe as high flexibility, high compression quality as well as coding efficiency. However in practice, with image quality guaranteed, keeping the coding rate in a certain rage was in the consideration so as to making the output of the encoder to adapt to channel bandwidth requirements. Yet, according to that improvement of coding performance led to more complicated algorithm, satisfied platform for algorithm processing needed higher speed and lower consumption in resources which were the superiorities of Davinci platform with promised future.The kernel of the work was study and improvement of H.264 rate control algorithm as well as realization on Davinci platform. Above all, developing of video coding standard had been introduced, also the characteristics of H.264 standard and construction of system. Then, two main improving methods aiming at deficiencies of JVT-G012 rate control algorithm had were advanced mainly on frame and basic unit layer rate controls:one is adding the consideration of complexity to bit distribution in frame layer target, where the time correlation of video sequence frames was applied sufficiently; another is reducing the algorithm complexity and enhancing coding efficiency by means of improving prediction way of basic unit layer MAD(mean absolute difference). The actual coding efficiency of improved algorithm was increased with closer bit rate to the target.By finished the proposed algorithm, the detailed introduction of Davinci technology had been given on hardware platform and software development framework. For the sake of properties made full use of, the algorithm was optimized in compilation, system and assembling to enhance the operating efficiency on Davinci platform. Creation and configuration of coding engine algorithm which had been packaged were achieved afterwards through following the engine software developing structure of Davinci technology. The purpose and benefits of the method were making other users focus on application of algorithm without considering the details. Finally, with the packaging algorithm invoked in use of application programming interface (API) provided by coding engine, the H.264 encoder which had better controlling of rate had been realized on Davinci platform.