Advances in Visual Data Compression and Communication

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26 2 Hybrid Video Coding

2.2 Technical Evolution

Although the framework of hybrid video coding has changed little in the past few

decades, compression technologies of motion compensation, transform, quantiza-

tion, and entropy coding have been continuously improving. Furthermore, new com-

pression technologies such as intra prediction, deblocking filtering, and sample adap-

tive offset (SAO) filtering are introduced into the framework. Next, we will compare

the compression technologies used in H.261 [8], MPEG-1 [9], MPEG-2 [10], MPEG-

4 [11], H.264 [12, 13], and HEVC [14]. By the comparison, we can clearly see the

trend of the developments on video compression.

2.2.1 H.261

H.261 is the first standard based on the hybrid video coding framework,