HDL Coder doesn't support AXI4-Lite Master mode yet. The current AXI4-Lite support is for slave mode only. You can use ARM processor to control the DMA controller, or use Xilinx AXI Master Lite IP if you want to control the DAM controller from your IP core directly. We are planning to support the AXI4-Lite master mode in the future releases.
The Sobel image processing demo is using both the AXI4-Stream Video master and slave interface. The Input video streaming is the slave interface, the output video streaming is the master interface.
Please let me know if you have any questions.