In-Network Quality Control of IP Camera Streams
Csaba Györgyi, Károly Kecskeméti, Péter Vörös, Sándor Laki, Géza Szabó · 2023
Manufacturing processes are often monitored by IP cameras. The generated video streams can be transferred via a wireless link to be processed and used by remote industrial controllers that manage and configure the industrial task in real-time. However, the link has limited bandwidth and is not capable of transmitting the aggregated traffic of all the IP cameras. Moreover, the platform provider of the remote controller (e.g., cloud) might charge extra fees for high volumes of network traffic. To optimize the data transport, we propose an in-network video quality control method for IP camera streams that drops non-essential frames from temporally irrelevant IP camera streams even when bandwidth is available. Our solution introduces a high-level API through which the operator can define which camera streams are needed with high quality at which actuator positions/states of the industrial process. Our method assumes an aggregation point that monitors the actuators' states and reduces the quality of camera streams that are not important for the control process, selectively dropping a set of video frames. We have implemented a P4-based prototype of the aggregation point and show that the remote controller can be fed with high-quality video streams while meeting bandwidth limitations and potentially saving data transfer costs without modifying the end-points.