Function opencv::gapi::filter_2d

source · 
pub fn filter_2d(
    src: &GMat,
    ddepth: i32,
    kernel: &Mat,
    anchor: Point,
    delta: Scalar,
    border_type: i32,
    border_value: Scalar
) -> Result<GMat>
Expand description

Convolves an image with the kernel.

The function applies an arbitrary linear filter to an image. When the aperture is partially outside the image, the function interpolates outlier pixel values according to the specified border mode.

The function does actually compute correlation, not the convolution:

block formula

That is, the kernel is not mirrored around the anchor point. If you need a real convolution, flip the kernel using flip and set the new anchor to (kernel.cols - anchor.x - 1, kernel.rows - anchor.y - 1).

Supported matrix data types are [CV_8UC1], [CV_8UC3], [CV_16UC1], [CV_16SC1], [CV_32FC1]. Output image must have the same size and number of channels an input image.

Note:

  • Rounding to nearest even is procedeed if hardware supports it, if not - to nearest.
  • Function textual ID is “org.opencv.imgproc.filters.filter2D”

Parameters

  • src: input image.
  • ddepth: desired depth of the destination image
  • kernel: convolution kernel (or rather a correlation kernel), a single-channel floating point matrix; if you want to apply different kernels to different channels, split the image into separate color planes using split and process them individually.
  • anchor: anchor of the kernel that indicates the relative position of a filtered point within the kernel; the anchor should lie within the kernel; default value (-1,-1) means that the anchor is at the kernel center.
  • delta: optional value added to the filtered pixels before storing them in dst.
  • borderType: pixel extrapolation method, see cv::BorderTypes
  • borderValue: border value in case of constant border type

See also

sepFilter

C++ default parameters

  • anchor: Point(-1,-1)
  • delta: Scalar(0)
  • border_type: BORDER_DEFAULT
  • border_value: Scalar(0)