milLII3yway's profile - activity

I assume you are the one who write this tutorial in OpenCV

http://docs.opencv.org/3.1.0/d5/d8f/m...

Do you have any idea, if I want to pass the type with 3 channels at the same time to thrust kernel (e.g. CV_8UC3, CV_32FC3)? I tried uchar3 and float3, but it seems their size are not the same as cv::Vec3b and cv::Vec3f.

Surely, I tried to send them each separately and they worked fine. Just want the code to be more compact. Thank you.

Thank you very much for your reply.

It seems that you are correct. I think this has something to do with OpenCL where you defined the kernel using text string. I am very new to these GPGPU. I guess this is quite common for people who using shading language.

I am trying to build my own ocl kernel in opencv 3.x. I was looking into both opencv source code and found out that the host source code calls ocl module (in *.cl file) using ocl::Kernel and ocl::ProgramSource (as mentioned in LINK and DOC).

It seems that in opencv module there is auto-generated *.hpp and *.cpp file (e.g. for modules/imgproc -> opencl_kernels_imgproc.hpp and opencl_kernels_imgproc.cpp) These files seemed to be generated based on *.cl file.

My question is, how to auto-generate these files for your custom kernel? I am guessing that it might be a CMAKE trick, but I cannot really found it. Would very much appreciated, if anyone could point me to the code/configure that do that.

Thank you.

** UPDATE ***

Seems to have something to do with

• cmake/cl2cpp.cmake
• cmake/OpenCVModule.cmake

Any idea to make use of it easily in your own application that will not be compiled with OpenCV?

I recently upgraded from OpenCV 2.4.9 to OpenCV 3.0.0 and found out that there is no module StereoVar anymore.

Do I miss anything? Will it be ported later?

I don't know whether this is directly related to opencv. It might be more like a computer vision question.

Assuming you have an essential matrix E for a stereo system, I would like to know the geometric interpretation of u, s, v' in term of the stereo system (e.g. epipole, baseline, ...), once you decompose E using SVD.

I tried to dig in to the geometric interpretation of SVD, and it seems that u, v' are the rotation matrix, while s are the scale. Though I cannot really related them to the geometric of the stereo system.

Thank you.