Motion Analysis and Object Tracking

accumulate

Adds an image to the accumulator.

C++: void accumulate(InputArray src, InputOutputArray dst, InputArray mask=noArray() )

Python: cv2.accumulate(src, dst[, mask]) → None

C: void cvAcc(const CvArr* src, CvArr* dst, const CvArr* mask=NULL )

Python: cv.Acc(src, dst, mask=None) → None

Parameters:

• src – Input image as 1- or 3-channel, 8-bit or 32-bit floating point.
• dst – Accumulator image with the same number of channels as input image, 32-bit or 64-bit floating-point.
• mask – Optional operation mask.

The function adds src or some of its elements to dst :

The function supports multi-channel images. Each channel is processed independently.

The functions accumulate* can be used, for example, to collect statistics of a scene background viewed by a still camera and for the further foreground-background segmentation.

See also

accumulateSquare(), accumulateProduct(), accumulateWeighted()

accumulateSquare

Adds the square of a source image to the accumulator.

C++: void accumulateSquare(InputArray src, InputOutputArray dst, InputArray mask=noArray() )

Python: cv2.accumulateSquare(src, dst[, mask]) → None

C: void cvSquareAcc(const CvArr* src, CvArr* dst, const CvArr* mask=NULL )

Python: cv.SquareAcc(src, dst, mask=None) → None

Parameters:

• src – Input image as 1- or 3-channel, 8-bit or 32-bit floating point.
• dst – Accumulator image with the same number of channels as input image, 32-bit or 64-bit floating-point.
• mask – Optional operation mask.

The function adds the input image src or its selected region, raised to a power of 2, to the accumulator dst :

The function supports multi-channel images. Each channel is processed independently.

See also

accumulateSquare(), accumulateProduct(), accumulateWeighted()

accumulateProduct

Adds the per-element product of two input images to the accumulator.

C++: void accumulateProduct(InputArray src1, InputArray src2, InputOutputArray dst, InputArray mask=noArray() )

Python: cv2.accumulateProduct(src1, src2, dst[, mask]) → None

C: void cvMultiplyAcc(const CvArr* src1, const CvArr* src2, CvArr* dst, const CvArr* mask=NULL )

Python: cv.MultiplyAcc(src1, src2, dst, mask=None) → None

Parameters:

• src1 – First input image, 1- or 3-channel, 8-bit or 32-bit floating point.
• src2 – Second input image of the same type and the same size as src1 .
• dst – Accumulator with the same number of channels as input images, 32-bit or 64-bit floating-point.
• mask – Optional operation mask.

The function adds the product of two images or their selected regions to the accumulator dst :

The function supports multi-channel images. Each channel is processed independently.

See also

accumulate(), accumulateSquare(), accumulateWeighted()

accumulateWeighted

Updates a running average.

C++: void accumulateWeighted(InputArray src, InputOutputArray dst, double alpha, InputArray mask=noArray() )

Python: cv2.accumulateWeighted(src, dst, alpha[, mask]) → None

C: void cvRunningAvg(const CvArr* src, CvArr* dst, double alpha, const CvArr* mask=NULL )

Python: cv.RunningAvg(src, dst, alpha, mask=None) → None

Parameters:

• src – Input image as 1- or 3-channel, 8-bit or 32-bit floating point.
• dst – Accumulator image with the same number of channels as input image, 32-bit or 64-bit floating-point.
• alpha – Weight of the input image.
• mask – Optional operation mask.

The function calculates the weighted sum of the input image src and the accumulator dst so that dst becomes a running average of a frame sequence:

That is, alpha regulates the update speed (how fast the accumulator “forgets” about earlier images). The function supports multi-channel images. Each channel is processed independently.

See also

accumulate(), accumulateSquare(), accumulateProduct()