binocular_distance_mgT_binocular_distance_mgBinocularDistanceMgBinocularDistanceMg (Operator)

Name

binocular_distance_mgT_binocular_distance_mgBinocularDistanceMgBinocularDistanceMg — Compute the distance values for a rectified stereo image pair using multigrid methods.

Signature

Description

binocular_distance_mgbinocular_distance_mgBinocularDistanceMgBinocularDistanceMgBinocularDistanceMg computes the distance values for a rectified stereo image pair using multigrid methods. The operator first calculates the disparities between two rectified images ImageRect1ImageRect1ImageRect1ImageRect1imageRect1 and ImageRect2ImageRect2ImageRect2ImageRect2imageRect2 similar to binocular_disparity_mgbinocular_disparity_mgBinocularDisparityMgBinocularDisparityMgBinocularDisparityMg. The resulting disparity values are then transformed into distance values of the corresponding 3D world points to the rectified stereo camera system as in disparity_to_distancedisparity_to_distanceDisparityToDistanceDisparityToDistanceDisparityToDistance. The distances are returned in the single-channel image DistanceDistanceDistanceDistancedistance in which each gray value represents the distance of the respective 3D world point to the stereo camera system. Different from binocular_distancebinocular_distanceBinocularDistanceBinocularDistanceBinocularDistance this operator uses a variational approach based on multigrid methods. This approach returns distance values also for image parts that contain no texture.

The input images ImageRect1ImageRect1ImageRect1ImageRect1imageRect1 and ImageRect2ImageRect2ImageRect2ImageRect2imageRect2 must be a pair of rectified stereo images, i.e., corresponding points must have the same row coordinate. In case this assumption is violated the images can be rectified by using the operators calibrate_camerascalibrate_camerasCalibrateCamerasCalibrateCamerasCalibrateCameras, gen_binocular_rectification_mapgen_binocular_rectification_mapGenBinocularRectificationMapGenBinocularRectificationMapGenBinocularRectificationMap and map_imagemap_imageMapImageMapImageMapImage.

For the transformation of the disparity to the distance, the internal camera parameters of the rectified camera 1 CamParamRect1CamParamRect1CamParamRect1CamParamRect1camParamRect1 and of the rectified camera 2 CamParamRect2CamParamRect2CamParamRect2CamParamRect2camParamRect2, as well as the relative pose of the cameras RelPoseRectRelPoseRectRelPoseRectRelPoseRectrelPoseRect must be specified. The relative pose defines a point transformation from the rectified camera system 2 to the rectified camera system 1. These parameters can be obtained from the operators calibrate_camerascalibrate_camerasCalibrateCamerasCalibrateCamerasCalibrateCameras and gen_binocular_rectification_mapgen_binocular_rectification_mapGenBinocularRectificationMapGenBinocularRectificationMapGenBinocularRectificationMap.

A detailed description of the algorithm and of the remaining parameters can be found in the documentation of binocular_disparity_mgbinocular_disparity_mgBinocularDisparityMgBinocularDisparityMgBinocularDisparityMg.

Attention

If using cameras with telecentric lenses, the DistanceDistanceDistanceDistancedistance is not defined as the distance of a point to the camera but as the distance from the point to the plane, defined by the y-axes of both cameras and their baseline (see gen_binocular_rectification_mapgen_binocular_rectification_mapGenBinocularRectificationMapGenBinocularRectificationMapGenBinocularRectificationMap).

For a stereo setup of mixed type (i.e., for a stereo setup in which one of the original cameras is a perspective camera and the other camera is a telecentric camera; see gen_binocular_rectification_mapgen_binocular_rectification_mapGenBinocularRectificationMapGenBinocularRectificationMapGenBinocularRectificationMap), the rectifying plane of the two cameras is in a position with respect to the object that would lead to very unintuitive distances. Therefore, binocular_distance_mgbinocular_distance_mgBinocularDistanceMgBinocularDistanceMgBinocularDistanceMg does not support a stereo setup of mixed type. For stereo setups of mixed type, please use reconstruct_surface_stereoreconstruct_surface_stereoReconstructSurfaceStereoReconstructSurfaceStereoReconstructSurfaceStereo, in which the reference coordinate system can be chosen arbitrarily. Alternatively, binocular_disparity_mgbinocular_disparity_mgBinocularDisparityMgBinocularDisparityMgBinocularDisparityMg and disparity_image_to_xyzdisparity_image_to_xyzDisparityImageToXyzDisparityImageToXyzDisparityImageToXyz might be used.

Additionally, stereo setups that contain cameras with and without hypercentric lenses at the same time are not supported.

Execution Information

• Multithreading type: reentrant (runs in parallel with non-exclusive operators).
• Multithreading scope: global (may be called from any thread).
• Automatically parallelized on tuple level.
• Automatically parallelized on internal data level.

Parameters

Result

If the parameter values are correct, binocular_distance_mgbinocular_distance_mgBinocularDistanceMgBinocularDistanceMgBinocularDistanceMg returns the value 2 (H_MSG_TRUE). If the input is empty (no input images are available) the behavior can be set via set_system('no_object_result',<Result>)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>). If necessary, an exception is raised.

Possible Predecessors

map_imagemap_imageMapImageMapImageMapImage

Possible Successors

thresholdthresholdThresholdThresholdThreshold

Alternatives

binocular_distancebinocular_distanceBinocularDistanceBinocularDistanceBinocularDistance, binocular_distance_msbinocular_distance_msBinocularDistanceMsBinocularDistanceMsBinocularDistanceMs, binocular_disparitybinocular_disparityBinocularDisparityBinocularDisparityBinocularDisparity, binocular_disparity_mgbinocular_disparity_mgBinocularDisparityMgBinocularDisparityMgBinocularDisparityMg, binocular_disparity_msbinocular_disparity_msBinocularDisparityMsBinocularDisparityMsBinocularDisparityMs

See also

map_imagemap_imageMapImageMapImageMapImage, gen_binocular_rectification_mapgen_binocular_rectification_mapGenBinocularRectificationMapGenBinocularRectificationMapGenBinocularRectificationMap, binocular_calibrationbinocular_calibrationBinocularCalibrationBinocularCalibrationBinocularCalibration, disparity_to_distancedisparity_to_distanceDisparityToDistanceDisparityToDistanceDisparityToDistance, distance_to_disparitydistance_to_disparityDistanceToDisparityDistanceToDisparityDistanceToDisparity, disparity_image_to_xyzdisparity_image_to_xyzDisparityImageToXyzDisparityImageToXyzDisparityImageToXyz

Module

3D Metrology