In Vitis libraries, all L1 flows are controlled by a tcl file named run_hls.tcl. The file for this lab can be found at L1/tests/jpegDec/run_ hls.tcl. Compared to L2 flow which is based on Opencl kernels, L1 flow allows users to quickly set the top-level functions so that they can focus more on a few functions of interests, analyze the performance bottlenecks of these functions, or run rapid synthesis and simulation without any source code modification.