Matrix Reductions ================= .. highlight:: cpp gpu::norm --------- Returns the norm of a matrix (or difference of two matrices). .. ocv:function:: double gpu::norm(InputArray src1, int normType) .. ocv:function:: double gpu::norm(InputArray src1, int normType, GpuMat& buf) .. ocv:function:: double gpu::norm(InputArray src1, int normType, InputArray mask, GpuMat& buf) .. ocv:function:: double gpu::norm(InputArray src1, InputArray src2, int normType=NORM_L2) :param src1: Source matrix. Any matrices except 64F are supported. :param src2: Second source matrix (if any) with the same size and type as ``src1``. :param normType: Norm type. ``NORM_L1`` , ``NORM_L2`` , and ``NORM_INF`` are supported for now. :param mask: optional operation mask; it must have the same size as ``src1`` and ``CV_8UC1`` type. :param buf: Optional buffer to avoid extra memory allocations. It is resized automatically. .. seealso:: :ocv:func:`norm` gpu::sum -------- Returns the sum of matrix elements. .. ocv:function:: Scalar gpu::sum(InputArray src) .. ocv:function:: Scalar gpu::sum(InputArray src, GpuMat& buf) .. ocv:function:: Scalar gpu::sum(InputArray src, InputArray mask, GpuMat& buf) :param src: Source image of any depth except for ``CV_64F`` . :param mask: optional operation mask; it must have the same size as ``src1`` and ``CV_8UC1`` type. :param buf: Optional buffer to avoid extra memory allocations. It is resized automatically. .. seealso:: :ocv:func:`sum` gpu::absSum ----------- Returns the sum of absolute values for matrix elements. .. ocv:function:: Scalar gpu::absSum(InputArray src) .. ocv:function:: Scalar gpu::absSum(InputArray src, GpuMat& buf) .. ocv:function:: Scalar gpu::absSum(InputArray src, InputArray mask, GpuMat& buf) :param src: Source image of any depth except for ``CV_64F`` . :param mask: optional operation mask; it must have the same size as ``src1`` and ``CV_8UC1`` type. :param buf: Optional buffer to avoid extra memory allocations. It is resized automatically. gpu::sqrSum ----------- Returns the squared sum of matrix elements. .. ocv:function:: Scalar gpu::sqrSum(InputArray src) .. ocv:function:: Scalar gpu::sqrSum(InputArray src, GpuMat& buf) .. ocv:function:: Scalar gpu::sqrSum(InputArray src, InputArray mask, GpuMat& buf) :param src: Source image of any depth except for ``CV_64F`` . :param mask: optional operation mask; it must have the same size as ``src1`` and ``CV_8UC1`` type. :param buf: Optional buffer to avoid extra memory allocations. It is resized automatically. gpu::minMax ----------- Finds global minimum and maximum matrix elements and returns their values. .. ocv:function:: void gpu::minMax(InputArray src, double* minVal, double* maxVal=0, InputArray mask=noArray()) .. ocv:function:: void gpu::minMax(InputArray src, double* minVal, double* maxVal, InputArray mask, GpuMat& buf) :param src: Single-channel source image. :param minVal: Pointer to the returned minimum value. Use ``NULL`` if not required. :param maxVal: Pointer to the returned maximum value. Use ``NULL`` if not required. :param mask: Optional mask to select a sub-matrix. :param buf: Optional buffer to avoid extra memory allocations. It is resized automatically. The function does not work with ``CV_64F`` images on GPUs with the compute capability < 1.3. .. seealso:: :ocv:func:`minMaxLoc` gpu::minMaxLoc -------------- Finds global minimum and maximum matrix elements and returns their values with locations. .. ocv:function:: void gpu::minMaxLoc(InputArray src, double* minVal, double* maxVal=0, Point* minLoc=0, Point* maxLoc=0, InputArray mask=noArray()) .. ocv:function:: void gpu::minMaxLoc(InputArray src, double* minVal, double* maxVal, Point* minLoc, Point* maxLoc, InputArray mask, GpuMat& valbuf, GpuMat& locbuf) :param src: Single-channel source image. :param minVal: Pointer to the returned minimum value. Use ``NULL`` if not required. :param maxVal: Pointer to the returned maximum value. Use ``NULL`` if not required. :param minLoc: Pointer to the returned minimum location. Use ``NULL`` if not required. :param maxLoc: Pointer to the returned maximum location. Use ``NULL`` if not required. :param mask: Optional mask to select a sub-matrix. :param valbuf: Optional values buffer to avoid extra memory allocations. It is resized automatically. :param locbuf: Optional locations buffer to avoid extra memory allocations. It is resized automatically. The function does not work with ``CV_64F`` images on GPU with the compute capability < 1.3. .. seealso:: :ocv:func:`minMaxLoc` gpu::countNonZero ----------------- Counts non-zero matrix elements. .. ocv:function:: int gpu::countNonZero(InputArray src) .. ocv:function:: int gpu::countNonZero(InputArray src, GpuMat& buf) :param src: Single-channel source image. :param buf: Optional buffer to avoid extra memory allocations. It is resized automatically. The function does not work with ``CV_64F`` images on GPUs with the compute capability < 1.3. .. seealso:: :ocv:func:`countNonZero` gpu::reduce ----------- Reduces a matrix to a vector. .. ocv:function:: void gpu::reduce(InputArray mtx, OutputArray vec, int dim, int reduceOp, int dtype = -1, Stream& stream = Stream::Null()) :param mtx: Source 2D matrix. :param vec: Destination vector. Its size and type is defined by ``dim`` and ``dtype`` parameters. :param dim: Dimension index along which the matrix is reduced. 0 means that the matrix is reduced to a single row. 1 means that the matrix is reduced to a single column. :param reduceOp: Reduction operation that could be one of the following: * **CV_REDUCE_SUM** The output is the sum of all rows/columns of the matrix. * **CV_REDUCE_AVG** The output is the mean vector of all rows/columns of the matrix. * **CV_REDUCE_MAX** The output is the maximum (column/row-wise) of all rows/columns of the matrix. * **CV_REDUCE_MIN** The output is the minimum (column/row-wise) of all rows/columns of the matrix. :param dtype: When it is negative, the destination vector will have the same type as the source matrix. Otherwise, its type will be ``CV_MAKE_TYPE(CV_MAT_DEPTH(dtype), mtx.channels())`` . :param stream: Stream for the asynchronous version. The function ``reduce`` reduces the matrix to a vector by treating the matrix rows/columns as a set of 1D vectors and performing the specified operation on the vectors until a single row/column is obtained. For example, the function can be used to compute horizontal and vertical projections of a raster image. In case of ``CV_REDUCE_SUM`` and ``CV_REDUCE_AVG`` , the output may have a larger element bit-depth to preserve accuracy. And multi-channel arrays are also supported in these two reduction modes. .. seealso:: :ocv:func:`reduce` gpu::meanStdDev --------------- Computes a mean value and a standard deviation of matrix elements. .. ocv:function:: void gpu::meanStdDev(InputArray mtx, Scalar& mean, Scalar& stddev) .. ocv:function:: void gpu::meanStdDev(InputArray mtx, Scalar& mean, Scalar& stddev, GpuMat& buf) :param mtx: Source matrix. ``CV_8UC1`` matrices are supported for now. :param mean: Mean value. :param stddev: Standard deviation value. :param buf: Optional buffer to avoid extra memory allocations. It is resized automatically. .. seealso:: :ocv:func:`meanStdDev` gpu::rectStdDev --------------- Computes a standard deviation of integral images. .. ocv:function:: void gpu::rectStdDev(InputArray src, InputArray sqr, OutputArray dst, Rect rect, Stream& stream = Stream::Null()) :param src: Source image. Only the ``CV_32SC1`` type is supported. :param sqr: Squared source image. Only the ``CV_32FC1`` type is supported. :param dst: Destination image with the same type and size as ``src`` . :param rect: Rectangular window. :param stream: Stream for the asynchronous version. gpu::normalize -------------- Normalizes the norm or value range of an array. .. ocv:function:: void gpu::normalize(InputArray src, OutputArray dst, double alpha = 1, double beta = 0, int norm_type = NORM_L2, int dtype = -1, InputArray mask = noArray()) .. ocv:function:: void gpu::normalize(InputArray src, OutputArray dst, double alpha, double beta, int norm_type, int dtype, InputArray mask, GpuMat& norm_buf, GpuMat& cvt_buf) :param src: Input array. :param dst: Output array of the same size as ``src`` . :param alpha: Norm value to normalize to or the lower range boundary in case of the range normalization. :param beta: Upper range boundary in case of the range normalization; it is not used for the norm normalization. :param normType: Normalization type ( ``NORM_MINMAX`` , ``NORM_L2`` , ``NORM_L1`` or ``NORM_INF`` ). :param dtype: When negative, the output array has the same type as ``src``; otherwise, it has the same number of channels as ``src`` and the depth ``=CV_MAT_DEPTH(dtype)``. :param mask: Optional operation mask. :param norm_buf: Optional buffer to avoid extra memory allocations. It is resized automatically. :param cvt_buf: Optional buffer to avoid extra memory allocations. It is resized automatically. .. seealso:: :ocv:func:`normalize` gpu::integral ------------- Computes an integral image. .. ocv:function:: void gpu::integral(InputArray src, OutputArray sum, Stream& stream = Stream::Null()) .. ocv:function:: void gpu::integral(InputArray src, OutputArray sum, GpuMat& buffer, Stream& stream = Stream::Null()) :param src: Source image. Only ``CV_8UC1`` images are supported for now. :param sum: Integral image containing 32-bit unsigned integer values packed into ``CV_32SC1`` . :param buffer: Optional buffer to avoid extra memory allocations. It is resized automatically. :param stream: Stream for the asynchronous version. .. seealso:: :ocv:func:`integral` gpu::sqrIntegral ---------------- Computes a squared integral image. .. ocv:function:: void gpu::sqrIntegral(InputArray src, OutputArray sqsum, Stream& stream = Stream::Null()) .. ocv:function:: void gpu::sqrIntegral(InputArray src, OutputArray sqsum, GpuMat& buf, Stream& stream = Stream::Null()) :param src: Source image. Only ``CV_8UC1`` images are supported for now. :param sqsum: Squared integral image containing 64-bit unsigned integer values packed into ``CV_64FC1`` . :param buf: Optional buffer to avoid extra memory allocations. It is resized automatically. :param stream: Stream for the asynchronous version.