标量(0,255,0)在opencv中不给出绿色线条

Har*_*han 9 opencv

我正在尝试在图像上绘制渐变线.我希望我的线条是绿色的,我使用Scalar(0,255,0).不过,我只有黑色.对于标量(0,0,0),我也变黑了.对于标量(255,255,255),我得到白色,但没有其他任何组合的颜色.部分代码如下:

line(visual_image,
     Point(x1*scaleFactor, y1*scaleFactor),
     Point(x2*scaleFactor, y2*scaleFactor),
     Scalar(0,255,0),
     1,8,0);
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ber*_*rak 17

由于无法将彩色线条,圆圈等绘制为灰度图像,因此必须先将其转换为3个通道:

Mat rgb;
cvtColor(visual_image, rgb, CV_GRAY2BGR); 
// now draw your lines:
line( rgb,
   Point(x1*scaleFactor, y1*scaleFactor),
   Point(x2*scaleFactor, y2*scaleFactor),
   Scalar(0,255,0),
   1,8,0);
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