Tunable Detection Targets | Checkerboard | SFRreg |
Accessing Detection Settings
The Target Detection Settings window is accessible by clicking “Target Detection Settings” at the bottom of the SFRreg Settings window:

If your target is difficult to detect, choose Manual Selection in the Target Detection Settings window. Then click Ok. Now, when you analyze the image in interactive mode, the Regmark Manual Selection window will appear.

Using the Registration Mark Manual Selection window, click on the center of each Reg Mark. Use Selection mode to click on RegMarks. Use Zoom/Pan mode to zoom on the mark to make it larger.

Continue clicking on the Reg Marks, until they all have been selected. You will see the X,Y values of each mark show up in the window to the right. If you need to remove one of the marks, click on the row, and click the “Remove Reg Mark” button. When all Regmarks have been marked, click continue, and the Analysis will continue.
Settings Fields
INI fields are found in the [sfrreg] section.
Setting Name | INI Field | Default INI Values | Allowed Ini Values | Description |
---|---|---|---|---|
Detection Method | regmark_detection_method | 0 | 0 = Autodetect, 1 = Manual | Autodetection of registration marks is guided by parameters such as number of SFRreg targets, minimum diameter, maximum diameter, contrast robustness, and rotation robustness. Manual Selection allows the user to click on the location of registration marks in an image. Manual Selection allows the user to click on the location of registration marks in an image. |
Number of SFRreg Targets | regmark_num | 0 | integer in the range [0,100] | Imatest will attempt to automatically determine the number of targets in an image, but if it fails to do so correctly the number can be manually set with this field. If empty or 0, the system will try to automatically determine how many targets there are. This is acceptable for most well-photographed setups. |
Minimum Diameter | minimum_diameter | 0 | number in range [0, maximum_diameter) | Use to filter out wrongly-detected image points that are smaller in diameter than the true targets. Smaller minimum diameter values correspond to increased memory requirements and longer detection times. If empty or 0, minimum size is max(1 % of the largest image dimension, 4 pixels). |
Maximum Diameter | maximum_diameter | 0 | number in the range [0, maximum image dimension) | Use to filter out wrongly-detected image points that are smaller in diameter than the true targets. There is no benefit to setting the max diameter to a value larger than the largest registration mark in an image. If empty or 0, maximum size is max(4% of the largest image dimension, geometric mean of minimum diameter and 1/8 of the largest image dimension). |
Contrast Robustness | regmark_contrast_opt | 0 | 0 = Good, 1 = Low, 2 = Very Low | Controls sensitivity to image contrast when searching for registration marks. Choose a higher value if low-contrast targets are not detected, or if there are false positive detections in image regions with significantly greater or lower pixel values than the true targets. A higher value will cause a slower detection. Increased contrast robustness (by choosing the low contrast or very low contrast options) corresponds to increased memory requirements and longer detection times. |
Rotation Robustness | regmark_rotation_opt | 0 | 0 = Basic, 1 = Advanced | Controls sensitivity to target rotations in the image. If targets rotated more than 10 degrees are not detected, setting this to advanced may help. Increased rotation robustness (by choosing the advanced option) corresponds to increased memory requirements and longer detection times. |
Use Manual Selection when Autodetect Fails (Interactive Only) | regmark_autofail_opt | 1 | 0 = unchecked, 1 = checked | If checked, the manual selection window will automatically open when autodetection of registration marks fails. Default is checked. |
Notes
- Previous Imatest versions (4.5 through 2020.1) had the following options available, but they were entered into fields found directly in the SFRreg More Settings window: Number of targets, Min and Max Diameter, Contrast Robustness, Rotation Robustness.