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Basic| Module: | OpenCV |
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Calculates an optical flow for a sparse feature set using the iterative Lucas-Kanade method with pyramids.
| Name | Type | Range | Description | |
|---|---|---|---|---|
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inPrevImg | Image | First UINT8 single-channel or 3-channel input image. | |
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inNextImg | Image | Second input image of the same size and the same type as inPrevImg. | |
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inPrevPts | Point2DArray | Vector of 2D points for which the flow needs to be found. | |
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inNextPts | Point2DArray | Input vector of initial points positions. When inUseInitialFlow is true, the vector must have the same size as in the input. | |
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inWinWidth | Integer | 1 -  |
Width of the search window at each pyramid level. |
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inWinHeight | Integer | 1 - |
Height of the search window at each pyramid level. |
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inMaxLevel | Integer | 0 - |
0-based maximal pyramid level number. If set to 0, pyramids are not used. If set to 1, two levels are used, and so on. |
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inTcEpsilon | Real | Criteria termination of the iterative process of corner refinement. Process stops when either after inTcMaxCount iterations or when the corner position moves by less than inTcEpsilon. | |
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inTcMaxCount | Integer | Criteria termination of the iterative process of corner refinement. Process stops when either after inTcMaxCount iterations or when the corner position moves by less than inTcEpsilon. | |
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inTcType | CvTerminationCriteria | Indicates which termination criteria will be used. | |
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inMinEigThreshold | Real | Not used. | |
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inUseInitialFlow | Bool | Use initial estimations stored in nextPts. If it is false, then prevPts is copied to nextPts and is considered as the initial estimate. | |
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outNextPts | Point2DArray | Output vector of 2D points containing the calculated new positions of input features in the second image. | |
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outStatus | IntegerArray | Output status vector. Each element of the vector is set to 1 if the flow for the corresponding features has been found. Otherwise, it is set to 0. | |
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outErr | RealArray | Output vector that contains the difference between patches around the original and moved points. | |
Errors
This filter can throw an exception to report error. Read how to deal with errors in Error Handling.
List of possible exceptions:
| Error type | Description |
|---|---|
| DomainError | inNextImg must have the same size, pixel type and depth as inPrevImg in cvCalcOpticalFlowPyrLK. |
| DomainError | inPrevImg must be UINT8 single-channel or 3-channel image in cvCalcOpticalFlowPyrLK. |
| DomainError | inPrevPts must have at least one point cvCalcOpticalFlowPyrLK. |
Complexity Level
This filter is available on Basic Complexity Level.
