FPGA uses sum of absolute difference for auto applications

JANUARY 15, 2009--Xilinx's Automotive (XA) Optical Flow for vision-based driver assistance (DA) systems is an FPGA implementation that integrates image-processing capabilities from Digital Design Corporation (DDC) to support applications including pedestrian detection, collision warning, sign recognition, blind spot detection, back-up, and parking aid. XA Optical Flow delivers scalable processing horsepower needed to implement pixel-level image processing functions that extract relative object motion information from a sequence of video frames.

XA Optical Flow is built on a Xilinx Spartan-3 and DDC Optical Flow IP core with motion estimation. The Optical Flow IP core extracts relevant information about the roadway environment from the video images provided by vehicle-based camera systems. The extracted motion images are segmented into separate objects (pixel blocks) and processed using a block-matching technique. The output is a two-dimensional vector map that can be used to assess collision threats.

The block-matching function requires a very high number of operations per second to perform sum of absolute difference (SAD) calculations across image frames. The Xilinx FPGA executes these operations in parallel, so in a single clock cycle multiple operations can be carried out. For more information, go to: http://press.xilinx.com/phoenix.zhtml?c=212763&p=irol-newsArticle&ID=1224851&highlight=