Creating a simple black image with opencv using cvcreateimage

Question

Very basic question coming from a newbie in OpenCV. I just want to create an image with every pixel set to 0 (black). I have used the following code in the main() function:

IplImage* imgScribble = cvCreateImage(cvSize(320, 240), 8, 3);

And what I get is a solid gray image, instead of the black one.

Thanks in advance !

Answer 1

What version of opencv you are using? For Mat,

#include <opencv2/opencv.hpp>
cv::Mat image(320, 240, CV_8UC3, cv::Scalar(0, 0, 0));

Answer 2

I can suggest two more altrnatives:

    IplImage* imgScribble = cvCreateImage(cvSize(320, 240), 8, 3);

    // Here you can set any color
    cvSet(imgScribble, cvScalar(0,0,0));


    // Here only black
    cvZero(imgScribble);