The statements in this section merely provide background information related to the present disclosure and are not admitted as prior art.
Moving Picture Experts Group (MPEG) and Video Coding Experts Group (VCEG) have developed video compression technology that is superior to the existing MPEG-4 Part 2 and H.263 standard. This new standard is called H.264/AVC (advanced video coding) and was jointly announced as MPEG-4 Part 10 AVC and ITU-T Recommendation H.264.
In H.264/AVC (hereinafter, simply referred to as H.264) standard, a residual signal is generated by performing an intra/inter prediction process in units of macroblocks having various types of sub-blocks, and encoding is performed by frequency transform, quantization, and entropy encoding in frequency transform units of 4×4 units with respect to the generated residual signal.
Video compression technologies are currently in development to meet the needs for ultra-high video resolution. The international standard organizations, MPEG and VCEG have jointly developed HEVC moving picture encoding standard in the name of JCT. In the ultra-high-resolution compression, experiments have proved that, in addition to 4×4 and 8×8 frequency units having been widely used in the existing video compression technologies, large frequency transform unit such as 16×16 is helpful to improve video compression efficiency. However, if such 16×16 unit is scanned and encoded at a time in the existing method, devising and implementing efficient frequency coefficient encoding is difficult.