**1.3.3 Data-level decomposition**

In data-level decomposition the work (data) is divided into smaller parts and each assigned to a different processor, as depicted in Fig.10b. Each processor runs the same program but on different (multiple) data elements (SPMD). In H.264 data decomposition can be applied at different levels of the data structure (see Fig.11), which goes down from Group of Pictures (GOP), to frames, slices, MBs, and finally to variable sized pixel blocks. Data-level parallelism can be exploited at each level of the data structure, each one having different constraints and requiring different parallelization methodologies.
