SoC handles in-car camera video with reduced latency

September 10, 2015 // By Graham Prophet
Renesas’ R-Car T2 SoC for vehicle camera networks enables transfer of high-resolution camera video through multiple systems with very low latency time of less than 1 msec; it is compliant with Ethernet AVB and incorporates an ultra-low-latency H.264 encoder

R-Car T2 system-on-a-chip (SoC) is an SoC dedicated for Ethernet AVB-enabled vehicle camera networks, complementing the company's R-Car Family devices for infotainment, instrument cluster and ADAS (Advanced Driver Assistance System) applications. The R-Car T2 enables the delivery of high-resolution camera video through multiple systems while maintaining real-time performance with low latency levels. These capabilities are key to providing the “surround view” monitoring and obstacle detection applications that contribute to safe driving experiences.

Initially used for rear-view functionality and parking assistance applications, the use of vehicle cameras has since expanded to support 360-degree “surround view” functionality that expands what is seen by the system to every direction around the vehicle, helping to improve driver safety. Vehicle camera video is also now being used in driver assist systems for braking, steering and providing obstacle detection warnings, for instance when changing lanes. These sophisticated systems demand substantially higher processing performance in order to handle the expanded range of image recognition targets and increased processing load imposed by multiple cameras with higher pixel counts. Ethernet AVB offers features such as guaranteed bandwidth and synchronisation of multiple cameras simultaneously, and a system involving additional cameras that can be flexibly upgraded.

The R-Car T2 supports multiple standards, including IEEE 802.1AS, IEEE802.1Qav, IEEE802.1Qat, and IEEE1722. The R-Car T2 SoC features a built-in H.264 encoder developed by Renesas to provide low-latency compression while maintaining real-time high-quality HD video (1,280 × 960) transfer. Video can be compressed with extremely low latency of less than 1 msec and delivered to multiple systems through the networks to vehicle systems. The high quality and real-time transfer create a high level of safety, making it possible to rapidly share camera footage with the advanced driver assist systems.

Previously, with the popularity of Ethernet as an easy-to-use network standard that allows video to be transferred to multiple systems, video compression was necessary as the maximum bandwidth supported by UTP cable is 100 Mbps, and latency was an issue in applications such as driver safety assist systems. Renesas says it has succeeded in reducing the latency time to less than 1 msec, which is equivalent to a movement distance of 2.8 cm when driving at 100 km/h. This enables nearly real-time data transfer, allowing use in driver safety assist systems and making it possible to switch from the current LVDS system to Ethernet.

Renesas Electronics Europe; www.renesas.eu

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