OpenCV：阈值和反转图像

Question

I'm trying to threshold and invert an image with Cinder OpenCV block. In openFrameworks I would use something like that:

someImage.threshold(230, true);

...where true is the parameter to specify to threshold and invert.

In Cinder I'm trying the following:

cv::threshold (input, threshNear, 230, 255, CV_THRESH_BINARY_INV);     

... that doesn't work, or

cv::threshold (input, threshNear, 100, 255, CV_8U);
cv::invert ( threshNear,  threshNearInverted);

...that produces and error and let the program stuck.

Any suggestion?

Answer 1

Ok, after more testing I've realized that actually the way to go is

 cv::threshold (input, threshNear, 70, 255, CV_THRESH_BINARY_INV);

the problem with the code I posted in my question looks like to be related with the threshold value I was trying to use (230 on 255). If I use a lower value (like for example 70 on 255) the color inversion actually works.