Stereo image processor and stereo image processing method

摘要

A stereo image processor (1) performs image matching, in an image matching section (6), on partial images of the same object included in a base image and a comparative image respectively and detects pixel-precision partial displacement between the base image and the comparative image based on a result of the image matching. Next, in an inverted phase filter processing section (9) in a second matching section (8), pixel values from the comparative image are filtered with an inverted phase filter using, as a filter coefficient, pixel values from the base image with the order thereof reversed, given the partial images of the same object that have minimum pixel-precision partial displacement. Then, in a peak detecting section (10), a peak position where an output value of the filtering with the inverted phase filter is maximum is detected and sub-pixel-precision partial displacement between the base image and the comparative image is detected based on the peak position. In this way, there is provided a stereo image processor that has improved accuracy of disparity calculation and analytical resolution and that requires less computation for disparity calculation and is capable of fast processing.

主权项

1. A stereo image processor, comprising:
a stereo image acquiring section including a first imaging system and a second imaging system, the stereo image acquiring section for acquiring a base image by taking an image of an object by the first imaging system and a comparative image by taking an image of the object by the second imaging system; an image matching section acquiring the base image and the comparative image from the stereo images, extracting a first partial image centered at a predetermined reference point from the base image with a first window function, and deriving a corresponding point from a predefined area in the comparative image, the corresponding point being a center point in a second partial image where a level of difference in image luminance is minimum relative to the first partial image; a filter section acquiring the base image and the comparative image from the stereo images, extracting a third partial image centered at a predetermined reference point from the base image with a second window function, extracting a fourth partial image centered at the corresponding point from the comparative image, and generating an output signal sequence based both on values of a sequence of luminance values of respective coordinate points included in the third partial image with an order thereof reversed with respect to coordinates and on luminance values of respective coordinate points included in the fourth partial image; and a peak position detecting section for detecting an output signal with a maximum output value from the acquired output signal sequence to determine disparity between the base image and the comparative image based on a position of the detected output signal in the output signal sequence.