Machine vision image sensor calibration

摘要

A system, apparatus, method, and computer readable media for calibration of one or more extrinsic image sensor parameters. A system may calibrate a multi-camera surround view system, for example as may be employed in a vehicle, based on image data comprising one or more ground plane landmarks. The system may determine a ground plane projection of the image data, for example through a Radon transformation. A signal associated with at least one of the one or more ground plane landmarks in the ground plane projection(s) may be determined, for example through application of the projection-slice theorem. The landmark signal may be utilized as a response in an automated calibration loop to optimize one or more extrinsic parameter values associated with the sensors.

主权项

1. A machine vision calibration system, comprising:
a plurality of image sensors to collect image data associated with multiple fields of view (FOV) encompassing adjacent portions of a ground plane having one or more ground plane calibration landmarks that comprise a pair of parallel lines, wherein:
a first of the image sensors is to collect first image data associated with a first FOV including at least a portion of a first of the parallel lines, but excluding a second of the parallel lines; anda second of the image sensors is to collect second image data associated with a second FOV including at least a portion of a second of the parallel lines, but excluding the first of the parallel lines; and an image sensor calibration module coupled to the image sensors and including logic to:
compute a two-dimensional ground plane projection of the collected image data based on a Radon transform of the image data for an angle corresponding to one or more extrinsic parameter values associated with the sensor that collected the image data, wherein to compute the projection, the calibration module includes logic to:
project the first image data in a first direction based on one or more first extrinsic parameter values associated with the first image sensor; andproject the second image data in a second direction based on one or more second extrinsic parameter values associated with the second image sensor;compute, from the ground plane projection, a first landmark signal associated with the pair of lines;evaluate the first landmark signal based on a parameterization of a pair of peaks in the signal associated with the pair of parallel lines; andselect one or more first extrinsic parameter values and one or more second extrinsic parameter values based on the evaluation of the first landmark signal.