Hark > Packages > HARK-OPENCV > HARK-OPENCV Tutorials > Image-based Segmentation and Object Tracking

Image-based Segmentation and Object Tracking

Main Sheet Configuration

  • Required Modules
    • CvfdWebcam
    • LOOP0 (This appears after you create iterator sheet.)

 

CvfdWebcam

All description is available at Image I/O.

 

LOOP0

All description is available at Image I/O.

 

 Iterator Sheet Configuration

  • Required Modules
    • CvfdQueryFrame
    • CvfdhCondensation
    • CvfdhDrawSrcRoi
    • CvfdhShowImage
    • CvfdhCameraSpecSetter
    • CvfdhSrcInfoTracker
    • CvfdhSrcInfoFormatConverter
    • DisplayLocalization

 

CvfdQueryFrame

All description is available at Image I/O.

 

CvfdhCondensation

  • Module Description

This module segments a specific colored object by particle filtering.
If you want to use other object segmentation, you can replace this module with a module in the following category.

Node list > FDOPENCV_HARK:Segmentation

 

  • Module Location
Node list > FDOPENCV_HARK:Segmentation > CvfdhCondensation

 

  • Property settings
Name Type Value Explanation
N_PARTICLE int 4000 Number of particles
N_STATES int 4 Order of states for each particle
SRC_TYPE string COG Definition of the output source
ROI_SIZE int 20 RoI size for each output source
TARGET_COLOR object <Vector<float> 0 0 255> Target color for segmentation in BGR values.

SRC_TYPE is now COG, so the center of gravity of all particles is output.
TARGET_COLOR is important for the color detection.

 

CvfdhDrawSrcRoi

  • Module Description

This module draws detected RoI windows on the input image stream with specific color and line width.

 

  • Module Location
Node list > FDOPENCV_HARK:ROI > CvfdhDrawSrcRoi

 

  • Property settings
Name Type Value Explanation
WINDOW_COLOUR object <Vector<int> 0 0 0> Color of RoI windows in RGB values
WINDOW_THICKNESS int 1 Line width of RoI windows
CENTER_COLOUR object <Vector<int> 0 0 0> Color of a RoI center dot in RGB values
CENTER_THICKNESS int 1 Line width of a RoI center dot

 

CvfdhShowImage

All description is available at Image I/O.

 

CvfdhCameraSpecSetter

  • Module Description

This module defines technical specification of your camera such as view angle, etc.

 

  • Module Location
Node list > FDOPENCV_HARK:Misc > CvfdhCameraSpecSetter

 

  • Property settings
Name Type Value Explanation
VIEW_ANGLE object <Vector<float> 40.0 30.0> View angles of your camera in horizontal and vertical axes.
TRANS_OFFSET object <Vector<float> 0.0 0.0> Horizontal and vertical offset of your camera for concatenating more than two images.
TRANS_OFFSET_SCALE object <Vector<float> 1.0 1.0> Horizontal and vertical scales for concatenating more than two camera images.
RADIUS_SCALE object 1.0 Diffusive scale for concatenating more than two camera images.
CAMERA_POS object <Vector<float> 0.0 0.0 0.0> 3D location of your camera from the basis

 

CvfdhSrcInfoTracker

  • Module Description

This module tracks each segment with a preferred manner.
This module is similar to SourceTracker in HARK audio processing.
The manner includes the size of RoI, aspect ratio of the RoI, life time of the RoI, and interval of RoIs.

 

  • Module Location
Node list > FDOPENCV_HARK:ROI > CvfdhSrcInfoTracker

 

  • Property settings
Name Type Value Explanation
USE_ROI_SIZE bool false If true the RoI selection based on the size is enabled.
ROI_SIZE object <Vector<int> 10 10> Specifies the maximum and minumum size of RoI for the selection. This is [x pixels * y pixels].
USE_ASPECT_RATIO bool false If true the RoI selection based on the aspect ratio is enabled.
ASPECT_RATIO object <Vector<float> 0.0 0.0> Specifies the maximum and minumum aspect ratio of RoIs for the selection. This is y [pixels / x pixels].
USE_PAUSE_LENGTH bool true If true the RoI elimination based on the life duration is enabled.
PAUSE_LENGTH float 100.0 Specifies the life duration of RoIs for the elimination.
USE_MIN_SRC_INTERVAL bool true If true the RoI elimination based on the interval is enabled.
SRC_INTERVAL float 100.0 Specifies the interval of RoIs for the elimination.
ENABLE_DEBUG bool false Output debug information if true.

 

CvfdhSrcInfoFormatConverter

  • Module Description

This module transforms the object tracking result to HARK source format.
The output of this module can be utilized for HARK audio processing.
To convert the object tracking result, you should specify the view angle of your camera in CvfdhCameraSpecSetter.

 

  • Module Location
Node list > FDOPENCV_HARK:ROI > CvfdhSrcInfoFormatConverter

 

  • Property settings

There is no parameter in this module.

 

DisplayLocalization

This is a HARK standard module.
Therefore, all description is available at HARK document.

 

 Examining the network file

Save the network file before closing [e.g.) cvColorTracker.n ] Connect your camera supported by OpenCV [e.g.) USB camera] Go to the terminal and run the HARK network file

./cvColorTracker.n

 

You’ll see the following two things:

  • A video stream in BaseImage window with a detected segment.
  • Time trajectory of the object tracking result in azimuth axis

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