This paper describes the adaptive deblocking filter used in the H.264/MPEG-4 AVC video coding standard. The filter performs simple operations to detect and analyze artifacts on coded block boundaries and attenuates those by applying a selected filter.

A unified approach to the coder control of video coding standards such as MPEG-2, H.263, MPEG-4, and the draft video coding standard H.264/AVC (advanced video coding) is presented. The performance of the various standards is compared by means of PSNR and subjective testing results. The results indicate that H.264/AVC compliant encoders typically achieve essentially the same reproduction quality as encoders that are compliant with the previous standards while typically requiring 60% or less of the bit rate.

We study and analyze the computational complexity of a software-based H.264/AVC (advanced video codec) baseline profile decoder. Our analysis is based on determining the number of basic computational operations required by a decoder to perform the key decoding subfunctions. The frequency of use of each of the required decoding subfunctions is empirically derived using bitstreams generated from two different encoders for a variety of content, resolutions and bit rates. Using the measured frequencies, estimates of the decoder time complexity for various hardware platforms can be determined. A detailed example is provided to assist in deriving time complexity estimates. We compare the resulting estimates to numbers measured for an optimized decoder on the Pentium 3 hardware platform. We then use those numbers to evaluate the dependence of the time complexity of each of the major decoder subfunctions on encoder characteristics, content, resolution and bit rate. Finally, we compare an H.264/AVC-compliant baseline decoder to a decoder that is compliant with the H.263 standard, which is currently dominant in interactive video applications. Both "C" only decoder implementations were compared on a Pentium 3 hardware platform. Our results indicate that an H.264/AVC baseline decoder is approximately 2.5 times more time complex than an H.263 baseline decoder.

A unified approach to the coder control of video coding standards such as MPEG-2, H.263, MPEG-4, and the draft video coding standard JVT/H.26L/AVC is presented. Using this unified framework, the performance of the various standards is compared by means of PSNR and subjective testing results. The results indicate that JVT/H.26L/AVC compliant encoding can typically achieve essentially the same objective PSNR reproduction quality as encoders that are compliant with previous standards while requiring as little as 60% or less of the bit rate of the next best standard, particularly for higher-latency applications and particularly for more difficult source material. Subjective testing shows that the bit savings produced by this draft standard are even larger than the PSNR results indicate.

We give a brief tour of the emerging ITU-T H.26L videocoding standard. Like its predecessors, H.26L is being designed partly for videoconferencing applications; however, many other applications are considered to be within the scope of the design effort and tests indicate that H.26L is fully suitable for a very broad range of applications. Starting from a clean slate, H.26L is a powerful new design that is forward-looking in its performance and scope of applications. We compare H.26L to the highest capabilities of the most complex and newest versions of prior standards such as H.263 and MPEG-4, and provide benchmarks for its performance. Our analysis indicates that the draft H.26L standard offers compelling advantages over all existing video coding standards. It has the potential to redraw the landscape of consumer and enterprise video applications.