Ryan Walker built a stereo vision board around the Rockchip RV1103 and wrote it up on Rootkit Labs. The RV1103 is a single core 1.1 GHz ARM Cortex-A7 SoC with 64 MB of DDR2 RAM and a MIPI CSI-2 bus in a QFN-88 package. The board carries two cameras and runs Linux, so it can do image capture and depth processing on its own.

The hardware is a four layer PCB with controlled impedance traces for USB, MIPI and Ethernet on the top layer and a solid ground plane below. The operating system image is built with Buildroot, using out of tree kernel support because the Rockchip MIPI drivers and hardware accelerators come from the vendor BSP. A serial console comes up first, then SSH over the USB-C port acting as an Ethernet adapter.

Depth comes from the Rockchip Video Engine, which includes a sum of absolute differences block. The software compares patches between the two OV9281 cameras, shifting one image horizontally until blocks match. The amount of shift is the depth value.…