mefmef's profile - activity

It seems that HOGCascade implementation in opencv2.4 is similar to this approach: "Fast Human Detection Using a Cascade of Histograms of Oriented Gradients" http://lear.inrialpes.fr/people/trigg...

So, it seems that in contrast to what @Dikay900 and @vpisarev mentioned, it is a valid implementation.

It seems that HOGCascade implementation in opencv2.4 is similar to this approach: "Fast Human Detection Using a Cascade of Histograms of Oriented Gradients" http://lear.inrialpes.fr/people/trigg...

So, it seems that in contrast to what @Dikay900 and @vpisarev mentioned, it is a valid implementation.

I think instead of dropping, the author of the code can write a document and describe the method.

They mentioned that "The implemented HOG features are quite weird - different from Dalal's interpretation of HOG, different from P. Dollar integral channel features"

I don't understand why it should be omitted if it is not the same as Dalal's interpretation!!! It was working very good and in many cases the results were better than Haar cascade and LBP!!

I've edited the question

It seems that opencv 3 no longer support HOG Cascade. Why is that?

in cascadedetect.cpp:

if( featureTypeStr == CC_HAAR )
    featureType = FeatureEvaluator::HAAR;
else if( featureTypeStr == CC_LBP )
    featureType = FeatureEvaluator::LBP;
else if( featureTypeStr == CC_HOG )
{
    featureType = FeatureEvaluator::HOG;
    CV_Error(Error::StsNotImplemented, "HOG cascade is not supported in 3.0");
}
else
    return false;

It was working very good and in many cases the results were better than Haar cascade and LBP!! Moreover, the training time was very good (in my experience 20 times faster than Haar and 2 times faster than LBP).

@Theoretiker Thanks for your comment. but I don't have these values! apertureWidth – Physical width in mm of the sensor. apertureHeight – Physical height in mm of the sensor.

Do you know how can i find that for Logitech c905 camera?

Thanks for your complete answer. Is it possible that instead of using solvepnp I fill rvec and tvec? Based on IMU data?

I have the rotation [Roll, Pitch, Yaw] and transition from the Z=0 plane which is [X, Y, Z].

If it is possible could you briefly tell me how can i fill rvec and tvec?

I calibrated my mono camera using opencv. Now I know the camera intrinsic matrix and distortion coefs [K1, K2, P1 ,P2,K3 ,K4, K5, K6] of my camera. Assuming that camera is place in [x, y, z] with [Roll, Pitch, Yaw] rotations. how can I get each pixel in world coordinate when the camera is looking on the floor [z=0].

After using opencv camera calibration, I do have the intrinsic and distortion_coefs of my camera. Is there an easy way to calculate the diagonal angle of view for my camera?

i have a picture that captured from a fixed position [X Y Z] and angle [Pitch Yaw Roll] and a focal length of F (i think this information is called camera matrix)

i want to change the captured picture to a different position like it was taken in up position

the result image should be like:

in fact i have picture taken from this position:

and i want to change my picture in a way that it was taken in this position:

i hope that i could express my problem.

thnx in advance