Architecture-aware Memory Access Scheduling for High-throughput Cascaded Classifiers

Cascaded classifier based object detectors are popular for many applications because of their high efficiency. Many researches have been devoted to developing the corresponding hardware accelerators. To reduce the circuit complexity while maintaining sufficient throughput, on-chip memories are commonly partitioned into several banks for parallel data access. However, since the coefficients of feature extraction are irregular, memory access conflict would frequently occur without proper scheduling. The proposed scheme explicitly schedules the access sequence as a post-processing for managing the coefficient memory. By formulating the desired sequence as a graph model, the classical graph coloring theory can then be adopted to solve the scheduling problem. In addition, the proposed graph model also considers the resource constraint on intermediate storage. Experimental results show that the throughput and area-efficiency of the target cascaded classifier can be greatly improved by adopting the proposed scheme as compared to the related work.