MOPEX Online Manual
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Overlap Modules: Detect (Outlier)
Namelist Trigger: run_detect_outlier
Output Directory Keyword: DETECT_DIR
Default Output Directory: <output_dir>/Detect
Depends on: Input files; Med Filter
Important Notes: Running this module does not automatically apply Bright Object Masking. The resulting bright object detection maps are only used if the mask_bright trigger is set to 1 in the namelist (see Overlap Namelist Options).
Output Directory Keyword: DETECT_DIR
Default Output Directory: <output_dir>/Detect
Depends on: Input files; Med Filter
Important Notes: Running this module does not automatically apply Bright Object Masking. The resulting bright object detection maps are only used if the mask_bright trigger is set to 1 in the namelist (see Overlap Namelist Options).
PURPOSE
-
Detect
performs image segmentation. This instance
is used only for bright object detection - i.e. to identify bright pixels (both spurious and astronomical) that should not contribute
to the background matching. In the Mosaic pipeline, it is
used for dual outlier detection as one part of several modules which
together identify outliers. Detect produces bright object detection maps.
PARAMETER BLOCK
-
&DETECT
Detection_Max_Area = 1000,
Detection_Min_Area = 0,
Detection_Threshold = 3,
Threshold_Type = 'simple',
&END
INPUTS
Detection_Max_Area: (int) The maximum area of a a single outlier identified in the detection map. If too large, it will be considered an extended object.
Detection_Min_Area: (int) The minimum area of a cluster to be detected.
Detection_Threshold: (float) The number of sigma above the mean for pixels included in clusters. Default value is 3.
Threshold Type: (char) There are three different ways to decide if a cluster of bright pixels will be segmentated into several clusters. The choices are simple, combo and peak (see Image Segmentation).
OUTPUTS
-
Generated Fits Files (*detmap.fits): The
stack of detection maps produced from interpolated BCD images.
Sources with positive signals, including both real science sources and
outliers from cosmic rays and badpixels, are set to the number of the
cluster membership. The background is zero in the segmentation
map.
DISCUSSION
In the Overlap pipeline, Detect (Outlier) is part of Bright Object Masking (mask_bright). The detection of bright pixels is performed on the background subtracted images (the output of Med Filter), which are in original pixels. The output is a set of mask images, one per input image, in which pixels corresponding to detected objects are set to a positive value. The mask images are saved in DETECT_DIR (if the keyword delete_intermediate_files is not set, or is set to 0). If mask_bright = 1 is set in the namelist then these masks will be used in the further processing.| Contents | ~ | Previous: Overlap Modules: Fiducial Image Frame | ~ | Next: Overlap Modules: Mosaic Interpolate |
