An automotive video camera exchanges various manufacturer-defined metadata, such as product codes, frame numbers, timestamps and error correction codes, with an ECU that controls it. Metadata is merged with a sensor’s video data, usually by embedding dedicated video lines within a single camera frame. The ECU recognizes such data and extracts it from the video.
This convenient camera control mechanism might become an obstacle in Hardware-in-the-Loop (HIL) validation setups that inject synthetically generated video from simulation environments or even previously recorded raw video data into the ECU under test. The most demanding HIL simulations that enable automotive Functional Safety (FuSa) testing require the ECU to run in the production firmware mode, instead of running in fault-tolerant debugging modes. Video generated within advanced simulation environments often includes fixed or even incomplete video camera’s metadata, while videos from test vehicles include metadata recorded and “frozen” at a certain time in the past.
When stimulated with the video containing metadata that doesn’t correspond to the ECU’s expectations based on issued control sequences, e.g. missing video brightness adjustments or a wrong frame number, the ECU under test can quickly encounter an invalid state and the HIL simulation will fail.
Xylon’s logiRECORDER Automotive HIL Video Logger used in the HIL mode with streaming data can overcome this problem by injecting simulated video data merged with the interactive metadata from the real video camera into the ECU. The ECU usually controls the video camera over the I2C bus tunneled via the LVDS that route through the logiRECORDER. Such a setup allows the ECU to continuously “talk” to the camera in real time and with an extremely low latency.
The logiRECORDER integrates programmable FPGA chips with hardware accelerators developed in-house, that merge the real camera’s metadata with the simulated video streamlined from the PC via a 10 Gigabit Ethernet data link.
Find out more about our HIL testing solution by clicking on the article below or downloading the PDF version here. You can access the full version of the April 2023 issue of Autonomous Vehicle International Magazine by following the link: https://www.ukimediaevents.com/publication/9cb6eeeb/84
