RegionPredetectionModes

RegionPredetectionModes controls how to find a region of interest (ROI) within the image or frame. It consists of one or more modes, each mode representing a different way to find a region of interest.

Candidate Mode List

• RPM_AUTO
• RPM_GENERAL
• RPM_GENERAL_RGB_CONTRAST
• RPM_GENERAL_GRAY_CONTRAST
• RPM_GENERAL_HSV_CONTRAST
• RPM_MANUAL_SPECIFICATION

RPM_AUTO

Lets the library automatically choose an algorithm to detect the region of interest(s).

RPM_GENERAL

Takes the whole image as a region of interest.

RPM_GENERAL_RGB_CONTRAST

Detects the ROI using the general algorithm based on RGB colour contrast. This mode has the following arguments for further customization.

• ImageParameterName
• MinImageDimension
• RelativeRegions
• Sensitivity
• SpatialIndexBlockSize

RPM_GENERAL_GRAY_CONTRAST

Detects the ROI using the general algorithm based on gray contrast. This mode has the following arguments for further customization.

• ImageParameterName
• MinImageDimension
• RelativeRegions
• Sensitivity
• SpatialIndexBlockSize

RPM_GENERAL_HSV_CONTRAST

Detects the ROI using the general algorithm based on HSV colour contrast. This mode has the following arguments for further customization.

• AspectRatioRange
• FindAccurateBoundary
• ForeAndBackgroundColours
• HeightRange
• ImageParameterName
• MinImageDimension
• RelativeRegions
• Sensitivity
• SpatialIndexBlockSize
• WidthRange

RPM_MANUAL_SPECIFICATION

Defines the ROI directly by specifying the region coordinates. This mode has the following arguments for further customizing.

• FirstPoint
• FourthPoint
• ImageParameterName
• MeasuredByPercentage
• RelativeRegions
• SecondPoint
• ThirdPoint

Setting Methods

As JSON Parameter

RegionPredetectionModes as a JSON parameter is a JSON Object array defined as below.

Default Value

{
    "RegionPredetectionModes":[
        {
            "Mode": "RPM_GENERAL"
        }
    ]
}

JSON Parameter Example

{
    "RegionPredetectionModes": [
        {
            "Mode": "RPM_GENERAL_RGB_CONTRAST", 
            "Sensitivity": 5
        },
        {
            "Mode": "RPM_GENERAL_HSV_CONTRAST", 
            "WidthRange": "[100, 200]"
        }
    ]
}

Candidate Argument List

• AspectRatioRange
• FindAccurateBoundary
• FirstPoint
• ForeAndBackgroundColours
• FourthPoint
• HeightRange
• ImageParameterName
• MeasuredByPercentage
• MinImageDimension
• RelativeRegions
• SecondPoint
• Sensitivity
• SpatialIndexBlockSize
• ThirdPoint
• WidthRange

AspectRatioRange

Specifies a set (or multiple sets) of aspect ratio range for filtering the predetected region.

Remarks

• A set of aspect ratio range is defined as [MinAspectRatio, MaxAspectRatio].
• Using a “”;”” to separate multiple sets.
• Value range of MinAspectRatio, MaxAspectRatio: [1,10000]
• Aspect ratio equals to height/width*100, while the height and width is from the bounding rectangle of the predetected region.

FindAccurateBoundary

Sets whether to enable finding accurate boundary.

Remarks

• 0: disable.
• 1: enable.

FirstPoint

Sets the first point of the region, which is usually the top-left corner.

Remarks

• A point is defined as [x-coordinate, y-coordinate].
• When MeasuredByPercentage = 0, the valid value range for x-coordinate and y-coordinate is [0, 0x7fffffff].
• When MeasuredByPercentage = 1, the valid value range for x-coordinate and y-coordinate is [0, 100].

ForeAndBackgroundColours

Specifies a set (or multiple sets) of the foreground and background colours used for region predetection algorithm.

Remarks

• This argument is mandatory for RPM_GENERAL_HSV_CONTRAST mode. If there is no manual setting, no region can be detected.
• A set of the foreground and background colours is defined as [ForegroundColour, BackgroundColour, Tolerance].
• Using a “”;”” to separate multiple sets.
• ForegroundColourand BackgroundColour are the Hue values in the HSV colour space for defining the foreground and background colours of the regions you want to predetect. The value -1 means black, gray, white.
• Tolerance is the allowable deviation of the Hue value defined by ForegroundColour.
• Value range of ForegroundColour, BackgroundColour: [-1,360]
• Value range of Tolerance: [0, 360]

FourthPoint

Sets the fourth point of the region, which is usually the top-left corner.

Remarks

• A point is defined as [x-coordinate, y-coordinate].
• When MeasuredByPercentage = 0, the valid value range for x-coordinate and y-coordinate is [0, 0x7fffffff].
• When MeasuredByPercentage = 1, the valid value range for x-coordinate and y-coordinate is [0, 100].

HeightRange

Specifies a set (or multiple sets) of height range for filtering the predetected region.

Remarks

• A set of height is defined as [MinHeight, MaxHeight].
• Using a “”;”” to separate multiple sets.
• Value range of MinHeight, MaxHeight: [1, 0x7fffffff]
• The height value is the height of the bounding rectangle of the predetected region.

ImageParameterName

Specifies the name of ImageParameter Object which defines the parameters used for predetected region results.

Remarks

Definition of An ImageParameter Object.

MeasuredByPercentage

Sets whether or not to use percentages to measure the coordinate.

MinImageDimension

Sets the minimum image dimension (in pixels) to enable region pre-detection.

Remarks

The library will enable the region pre-detection feature only when the image dimension is larger than the given value.

RelativeRegions

Sets the regions relative to the predetected region.

Remarks

• Each region need to be defined as [Left, Top, Right, Bottom, Index]. If you want to define multiple regions, you can use a “”;”” to separate them.
• Left, Top, Right, Bottom are four percentage values relative to top-left corner of the predetected region.
• Index means the index of a specific colour set in ForeAndBackgroundColours which the current region is applied to. If the value of index is set to -1, the current region will be applied to all colour sets in ForeAndBackgroundColours.
• Value range of Left, Top, Right, Bottom: [-10000,10000]
• Value range of Index: [-1, 0x7fffffff]

SecondPoint

Sets the second point of the region, which is usually the top-left corner.

Remarks

• A point is defined as [x-coordinate, y-coordinate].
• When MeasuredByPercentage = 0, the valid value range for x-coordinate and y-coordinate is [0, 0x7fffffff].
• When MeasuredByPercentage = 1, the valid value range for x-coordinate and y-coordinate is [0, 100].

Sensitivity

Sets the sensitivity used for region predetection algorithm.

Remarks

A larger value means the library will take more effort to detect regions.

SpatialIndexBlockSize

Sets the spatial index block size used for region predetection algorithm.

Remarks

The block size used for region predetection would be 2 to the power of N. The allowed values of SpatialIndexBlockSize is the power number (N=1,2,3…).

ThirdPoint

Sets the third point of the region, which is usually the top-left corner.

Remarks

• A point is defined as [x-coordinate, y-coordinate].
• When MeasuredByPercentage = 0, the valid value range for x-coordinate and y-coordinate is [0, 0x7fffffff].
• When MeasuredByPercentage = 1, the valid value range for x-coordinate and y-coordinate is [0, 100].

WidthRange

Specifies a set (or multiple sets) of width range for filtering the predetected region.

Remarks

• A set of width is defined as [MinWidth, MaxWidth].
• Using a “”;”” to separate multiple sets.
• Value range of MinWidth, MaxWidth: [1, 0x7fffffff]
• The width value is the width of the bounding rectangle of the predetected region.