Scorpion supports a image filter command strings to perform image filtering to an image, either pre-filter or post-filter.

These filters are supported by various tools like TemplateFinder3 and ColorSegmentor.

The filter format is given by a command string where filter type is given by a single letter followed by one or more parameters.

• <cmd><p1><,p2><,pn>

Multiple filters can be combined in any sequence. Some filters are optimized by threading, this applies mainly for larger images (>VGA) and may be tuned due to image size, filter aperture and no of cpu's.

Supported filters:

• c - canny
  • c<threshold1=40>,<threshold2=200>,<aperturesize=3>,<threads=4>
• d- dilate
  • d<iterations=1>,<threads=n>
  • example - d2
• e- erode
  • e<iterations=1>,<threads=n>
  • example - e4
• C - close:
  • C<iterations=4>,<threads=n>
  • example - C2
• O - open:
  • O<iterations=4>,<threads=n>
  • example  - O4
• l - laplace:
  • l<aperture=3>,<threads=n>
  • example - l3
• t - adaptiveThreshold:
  • t<maxvalue=125>,<adaptive_method=MEAN(0)>,<thresh_type=BIN(0)>,<block_size=3>,<param1=5>
    
• g - Gaussian :
  • g<size1=3>,<size2=0>,<sigma1=0>,<sigma2>,<threads=n>
• b - Blur:
  • b<size1=3>,<threads=n>
• m - Median:
  • m<size1=3>,<threads=n>
• s - Sobel:
  • s<xorder=1><yorder=1><aperture_size=3>,<threads=n>
• H - Threshold:
  • H<threshold=100><maxvalue=255><threshold_type=0>,<threads=n>
• h - equalize histogram
• R - Sort:
  • R<flags=0>
• f - flip:
  • f<horiz=0> - flip vertical or horizontal
• N - Normalize:
  • N<aperture=21><scale=255><percentile=50><threads=n>
    • percentile is currently fixed at 50 but has to be specified if threads is to be specified
• F - Fill holes:
  • F<mode><maxarea=100><maxdev=5><minnbr=0><maxnbr=255><minint=0><maxint=0><minholes=0><maxholes=MAXINT><minarea=0>
• | - threads:
  • no of threads used for following commands, '|' - PIPE chacter

Note 1: The filters where first implemented in STC-0011-ImageFilter

Note 2: Many of the image processing filter parameters must be odd values

Example 1: Canny and erode

• c40e2

Example 2: Image blur

• b5
  

Example 3: Adaptive Threshold

• t125,0,0,5

Example 4: Fill undefined holes in heightmap

• F0,500,10 - fill holes less or equal 500 pixels where pixel value is 0 (undefined) and pixel deviation of each row in hole is less or equal 10