Message propagation-based stereo image matching system

A stereo image matching system, comprising:

• an image processing unit for converting input images inputted from a first and a second image acquisition unit into digital signals to output first and second pixel data;
• and
• an image matching unit for computing at least two of an upward, a downward, a forward and a backward message of each pixel by using data values of the first and the second pixel data that are located on a same epipolar line to calculate a disparity value of each pixel, and iteratively repeating said computation by exchanging matching information between adjacent pixels from locations of pixels adjacent a current location of pixels in a 2D grid structure of an image to locations of peripheral pixels, and collecting the messages propagated from peripheral pixels,
• wherein the image matching unit includes:
• a scan line buffer for storing therein the right and the left side image pixel data;
• a forward processor for receiving the right and the left side image pixel data to compute a forward message;
• a stack for saving the forward message computed by the forward processor;
• a backward processor for receiving the right and the left side image pixel data to compute a backward message;
• and
• a disparity computation processor for receiving the right and the left side image pixel data, the forward message from the stack, and the backward message to compute the disparity value, and
• wherein, in order to calculate the message, the forward, backward, upward and downward processors include:
• a matching cost processor for receiving the right and the left side image pixel data to compute a matching cost;
• a forward cost processor for receiving the matching cost and multiple message values to compute a forward cost;
• a stack for receiving and storing therein the forward cost;
• a backward cost processor for receiving the forward cost from the stack to compute a backward cost;
• and
• a recursive buffer for allowing the backward cost to be recursively used for subsequent processing.