DaNiKhan V‑Window

DaNiKhan Virtual Window: A virtual window just using your webcam.

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C API Documentation

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This is the API Documentation for the C Interface of dnkvw.

IDnkvwHandle dnkvw_createContext();

This method creates a new dnkvw context. It is needed for all operations in this library. Do not forget to free it after you are done with it.

Returns:

  • the newly created context
void dnkvw_freeContext(IDnkvwHandle* context);

This method deinitializes and frees a dnkw context. If you use C NEVER use ‘free()’ to free an existing context. Only use this method to free a context.

Parameters:

  • context a pointer to an initialized context
void dnkvw_setLogLevel(IDnkvwHandle context, int logLevel);

Set the log level.

Parameters:

  • context an initialized dnkvw context
  • logLevel the log level

Logging defaults:

  • Debug: Dnkvw = Verbose
  • Release: Dnkvw = Warning
void dnkvw_setInternalLogLevel(IDnkvwHandle context, int internalLogLevel);

Set the internal log level. Not intended for production use.

Parameters:

  • context an initialized dnkvw context
  • internalLogLevel the log level

Logging defaults:

  • Debug: Internal = Silent
  • Release: Internal = Silent
int dnkvw_selectHaarTracker(IDnkvwHandle context);

Use Haar tracking. Overwrites previously selected tracker.

Parameters:

  • context an initialized dnkvw context

Returns:

  • 1 if the selection was successful, 0 if not
int dnkvw_selectDnnTracker(IDnkvwHandle context);

Use DNN tracking. Overwrites previously selected tracker.

Parameters:

  • context an initialized dnkvw context

Returns:

  • 1 if the selection was successful, 0 if not
int dnkvw_startTracking(IDnkvwHandle context, int cameraId);

Starts the tracking.

Parameters:

  • context an initialized dnkvw context
  • cameraId the Id of the camera to be uses for tracking

Returns:

  • 1 if the tracking could be started successfully. A 0 value may indicate a problem with the camera.
void dnkvw_stopTracking(IDnkvwHandle context);

Stops the tracking. This function may block.

Parameters:

  • context an initialized dnkvw context
void dnkvw_stopTrackingAsync(IDnkvwHandle context);

Stops the tracking as soon as possible without blocking.

Parameters:

  • context an initialized dnkvw context
void dnkvw_configureFrustum(IDnkvwHandle context, float aspectRatio, float nearPlane);

Configures the viewing frustum according to the parameters.

Parameters:

  • context an initialized dnkvw context
  • aspectRatio the aspect ratio
  • nearPlane the near plane
void dnkvw_calibrate(IDnkvwHandle context);

Runs a short calibration routine. The user should sit or stand as centered as possible before this function is called. The position of the user will be used as the new center until a new calibration is started.

This method should be called shortly after the start of the tracking to correct perspective problems caused by a wrong starting center.

Parameters:

  • context an initialized dnkvw context
void dnkvw_loadFrustum(IDnkvwHandle context, float* left, float* right, float* top, float* bottom);

Get the last frustum. The viewing frustum is the volume that may appear on the screen. It is described by a near plane, a far plane and the distances of the left, right, top and bottom plane based on the near plane. This function returns only the left, right, top and bottom values. The near and far plane can be set independently.

These values can be used to calculate the projection matrix. This is normally done by your 3D graphics framework. Look at our demos for some case specific examples.

For more information see https://en.wikipedia.org/wiki/Viewing_frustum

Parameters:

  • context an initialized dnkvw context
  • left a pointer to a float where the left result can be saved
  • right a pointer to a float where the right result can be saved
  • top a pointer to a float where the top result can be saved
  • bottom a pointer to a float where the bottom result can be saved
void dnkvw_loadEyeOffset(IDnkvwHandle context, float* x, float* y, float* z);

Get the last calculated eye offset.

Parameters:

  • context an initialized dnkvw context
  • x a pointer to a float where the X result can be saved
  • y a pointer to a float where the Y result can be saved
  • z a pointer to a float where the Z result can be saved
void dnkvw_loadFps(IDnkvwHandle context, float* fps);

Get the last FPS value.

Parameters:

  • context an initialized dnkvw context
  • fps a pointer to a float where the result can be saved
void dnkvw_debugCameraInput(IDnkvwHandle context, int cameraId);

Debugging function to test the camera input. Should not be called while the tracking thread is running. This function may block. Don’t use this in production code.

Parameters:

  • context an initialized dnkvw context
  • cameraId Id of the camera to use for tracking
void dnkvw_debugCameraFace(IDnkvwHandle context, int cameraId);

Debugging function to test the face detection. Should not be called while the tracking thread is running. This function may block.
Don’t use this in production code.

Parameters:

  • context an initialized dnkvw context
  • cameraId Id of the camera to use for tracking