This paper presents the design of a high throughput multitransform and multiparallelism IP for H.264/AVC standard. This solution supports the five H.264/AVC transforms and it supports five different levels of parallelism. The proposed architecture were described in VHDL and synthesized to Altera Stratix and Xilinx Virtex-II Pro FPGAs and to TSMC 0.35/spl mu/m standard cells. The multitransform and multiparallelism architecture mapped to FPGAs could process from 124 millions to 3.2 billions of samples per second, depending on the parallelism level selected. The standard cells version could process from 218.7 millions to 3.5 billions of samples per second. These results indicate that the proposed solution presents a high flexibility and that this solution is able to be used in various H.264/AVC codecs with different performance requirements. The performance results of all experiments realized indicated that this architecture is able to be used in high definition applications, like HDTV.