merge_cont_line_scan_xld ( CurrConts, PrevConts : CurrMergedConts, PrevMergedConts : ImageHeight, Margin, MergeBorder, MaxImagesCont : )

Merge XLD contours from successive line scan images.

The operator merge_cont_line_scan_xld connects adjacent XLD contours, which were extracted from adjacent images with the height ImageHeight. This operator was especially designed to connect contours that were extracted from images grabbed by a line scan camera. CurrConts contains the contours from the current image and PrevConts the contours from the previous one.

With the help of the parameter MergeBorder two cases can be distinguished: If the top (first) line of the current image touches the bottom (last) line of the previous image, MergeBorder must be set to 'top', otherwise set MergeBorder to 'bottom'. MergeBorder defines a margin to the border. Only those end points of the contours which are inside this margin are considered for the following merging process.

If the operator merge_cont_line_scan_xld is used recursivly, the parameter MaxImagesCont determines the maximum number of images which are covered by a merged contour. All points of the merged contour from an older image are removed.

The operator merge_cont_line_scan_xld returns two contour arrays. PrevMergedConts contains all those contours from the previous input contours PrevConts, which could not be merged with a current contour. CurrMergedConts collects all current contours together with the merged parts from the previous images. Merged contours will exceed the original image, because the previous contours are moved upward (MergeBorder='top') or downward (MergeBorder='bottom') according to the image height.


Parameters

CurrConts (input_object)
xld_cont(-array) -> object
Current input contours.

PrevConts (input_object)
xld_cont(-array) -> object
Merged contours from the previous iteration.

CurrMergedConts (output_object)
xld_cont(-array) -> object
Current contours, merged with old ones where applicable.

PrevMergedConts (output_object)
xld_cont(-array) -> object
Contours from the previous iteration which could not be merged with the current ones.

ImageHeight (input_control)
integer -> integer
Height of the line scan images.
Default value: 512
List of values: 240, 480, 512

Margin (input_control)
real -> real
Maximum distance of contours from the image border.
Default value: 0
List of values: 0, 1, 2, 3, 4, 5

MergeBorder (input_control)
string -> string
Image line of the current image, which touches the previous image.
Default value: ''top''
List of values: ''top'', ''bottom''

MaxImagesCont (input_control)
integer -> integer
Maximum number of images covered by one contour.
Default value: 3
Suggested values: 1, 2, 3, 4, 5


Result

The operator merge_cont_line_scan_xld returns the value 2 (H_MSG_TRUE) if the given parameters are correct. Otherwise, an exception will be raised.


Parallelization Information

merge_cont_line_scan_xld is reentrant and processed without parallelization.


Module

Sub-pixel operators



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