Schemas of block adjustment tables

The block adjustment workflow can produce many different table outputs. This topic will discuss the fields that exist within each of the tables.

Control point table

The control point table stores the information needed for the tie points, ground control points (GCPs), and check points. This table is initially generated by the Compute Tie Points tool. The table can be updated using the Compute Control Points tool, or the Block Adjustment window.

Field name	Description
ImageID	The image identification number. This will be the same value as the OBJECTID field in the mosaic dataset footprint table.
PointID	The point identification number. This value will represent the same point location over the various overlapped images.
Type	A code to define the type of control point that the row represents: 1 = Tie point 2 = Ground control point 3 = Check point
Status	A code to define the status of the point: 1 = The points are used in the block adjustment computation. 2 = The points are not used in the block adjustment computation.
Score	A score that is generated by the matching algorithm, which is based on image correlation. The value range for the score is 0.0 to 1.0, where a score of 0 is the best match.
Rays	The number of points that have the same PointID.
V1 and V2	If the Type field is equal to 1 (tie point), then V1 is the x-coordinate of the tie point, and V2 is the y-coordinate of the tie point.
	If the Type field is equal to 2 or 3 (GCP or check point), then the values indicate the accuracy of the control points, expressed in meters: V1 is the x.y accuracy of the control point. V2 is z accuracy of the control point. If the x,y accuracy or z accuracy is not available, a value of -2 means that the accuracy is unknown. If you want the system to calculate the accuracy, type a value of -1 in the field.

Solution table

The solution table stores the transformation for each image and its associated root mean square (RMS). This table is generated by the Compute Block Adjustments tool.

Field name	Description
ImageID	The image identification number. This will be the same value as the OBJECTID field in the mosaic dataset footprint table.
RMS	The RMS of the solution points. The RMS is expressed in pixel units.
Quality	The quality of the adjustment for each image. A value of 1 is the best quality.
Data	The computed adjustment result that is stored as a binary large object (BLOB). The result will be applied to the corresponding image in the mosaic dataset when you run the Apply Block Adjustment tool.

Adjustment quality table

The adjustment quality table stores the details of the adjustment quality of the overlapping areas. This table is generated by the Compute Block Adjustments tool.

Field name	Description
ImageID	The image identification of the first image.
ImageID2	The image identification of the second image.
lD	The list of overlapping image IDs, delimited by a period.
PointCount	The number of points in the overlapped area of the image pair.
BlunderCount	The number of points with large errors. These points will be excluded from the adjustment computation.
BHR	The base-to-height ratio (BHR) of the two images.
ViewAngle	The intersection angle of the two images.
MaximumGSD	The maximum ground sample distance (GSD) of the two images.
MosaicMeanError	The average value of the mosaic errors of the two images. The mosaic error for each PointID is meters and is calculated as the difference of the solution points in map space.
Mosaic RMSE	The root mean square of the mosaic dataset error of the two images. This is expressed in meters. A quality mosaic will have similar values for Mosaic RMSE and MaximumGSD.
EpipolarDistanceRMS	The root mean square of epipolar distance, which is the distance of the solution points to the epipolar line.

Overlap table

The overlap table stores the polygons of the image overlap areas, and the associated statistics for each of the overlaps. It is generated by the Analyze Control Points tool.

Field name	Description
Count	The number of overlapping images.
ID	The list of overlapping image IDs, delimited by a period.
PointCount	The number of points in the overlapping area.
PointCoverage	The percentage of points in the overlapping area. This percentage is expressed as a decimal. For instance, a percent of 55 percent would be shown as 0.55.
Multirays	The number of unique PointIDs.
Mask	A coded field that indicates whether the row will be used when computing tie points or control points: 1 = Rows that will be excluded in the computation. 2 = Rows that will used in the computation.

Coverage table

The coverage table stores a convex polygon that delineates the area covered by the tie points or the control points. This tool is generated by the Analyze Control Points tool.

Field name	Description
ImageID	The image identification number.
Coverage	The percentage of the image that is covered by the control points. The covered area is created by using a convex polygon of all the control points.
Count	The number of points per image.
Multirays	The number of unique PointIDs.