draw_line_mask

cbclib.bin.draw_line_mask(shape: Tuple[int, Ellipsis], lines: Union[numpy.ndarray, Sequence[numpy.ndarray]], max_val: int = 255, dilation: float = 0.0, profile: str = 'tophat')

Draw thick lines with variable thickness and the antialiasing applied on a single frame by using the Bresenham’s algorithm [BSH]. The lines must follow the LSD convention, see the parameters for more info.

Parameters

• inp – Input array.

• lines (Union[numpy.ndarray, Sequence[numpy.ndarray]]) –

  An array of the detected lines. Must have a shape of (N, 7), where N is the number of lines. Each line is comprised of 7 parameters as follows:

  • [x0, y0], [x1, y1] : The coordinates of the line’s ends.

  • width : Line’s width.

  • p : Angle precision [0, 1] given by angle tolerance over 180 degree.

  • -log10(NFA) : Number of false alarms.

• max_val (int) – Maximum pixel value of a drawn line.

• dilation (float) – Size of the binary dilation applied to the output array.

• profile (str) –

  Line width profiles. The following keyword values are allowed:

  • tophat : Top-hat (rectangular) function profile.

  • linear : Linear (triangular) function profile.

  • quad : Quadratic (parabola) function profile.

  • gauss : Gaussian funtion profile.

Raises

• ValueError – If inp is not a 2-dimensional array.

• ValueError – If lines has an incompatible shape.

• RuntimeError – If C backend exited with error.

References

BSH

“Bresenham’s line algorithm.” Wikipedia, Wikimedia Foundation, 20 Sept. 2022, https://en.wikipedia.org/wiki/Bresenham%27s_line_algorithm.

Returns

Output array with the lines drawn.

Return type

numpy.ndarray

See also

cbclib.bin.LSD : Line Segment Detector.