1 | initial version |

Depending on your application, you could draw circles around the points instead of making the pixels specifically coloured. There are OpenCV functions to do this. But yes, you can change the color at that specific instance to black by doing something like this --> `image.at<uchar>(Points(x, y)) = 0;`

2 | No.2 Revision |

Depending on your application, you could draw circles around the points instead of making the pixels specifically coloured. There are OpenCV functions to do this. But yes, you can change the color at that specific instance to black by doing something like this --> `image.at<uchar>(Points(x, y)) = 0;`

Edit: Here is the function for drawing a circle around a point

`circle(image, co-ordinates, radius, color)`

--> Where image is the source image, co-ordinates are the points where you want the center of the circle to be (Point(x,y)), radius is an integer value with the circle radius, and color is the color of the circle. (Scalar(0, 0, 0) for a black circle).

3 | No.3 Revision |

`image.at<uchar>(Points(x, y)) = 0;`

Edit: Here is the function for drawing a circle around a point

`circle(image, co-ordinates, radius, color)`

--> Where image is the source image, co-ordinates are the points where you want the center of the circle to be (Point(x,y)), radius is an integer value with the circle radius, and color is the color of the circle. (Scalar(0, 0, 0) for a black circle).

4 | No.4 Revision |

`image.at<uchar>(Points(x, y)) = 0;`

~~Edit: ~~**Edit:** Here is the function for drawing a circle around a point

`circle(image, co-ordinates, radius, color)`

--> Where image is the source image, co-ordinates are the points where you want the center of the circle to be (Point(x,y)), radius is an integer value with the circle radius, and color is the color of the circle. (Scalar(0, 0, 0) for a black circle).

5 | No.5 Revision |

`image.at<uchar>(Points(x, y)) = 0;`

**Edit:** Here is the function for drawing a circle around a point

`circle(image, co-ordinates, radius, color)`

--> Where image is the source image, co-ordinates are the points where you want the center of the circle to be (Point(x,y)), radius is an integer value with the circle radius, and color is the color of the circle. (Scalar(0, 0, 0) for a black circle).

6 | No.6 Revision |

`image.at<uchar>(Points(x, y)) = 0;`

**Edit:** Here is the function for drawing a circle around a point
`circle(image, co-ordinates, radius, color)`

--> Where image is the source image, co-ordinates are the points where you want the center of the circle to be (Point(x,y)), radius is an integer value with the circle radius, and color is the color of the circle. (Scalar(0, 0, 0) for a black circle).

Additionally, you could also create a rectangle with your four points as the edges.

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