This would be a related (unanswered ) question: http://answers.opencv.org/question/38848/opencv-displaying-umat-efficiently/ As I don't see any related constructors for the Umat, the easiest starting point would be to ask in the forum. This will probably get faster results, than diving into the code ourselves.
2014-12-08 15:59 GMT+01:00 Simon Danisch <sdani...@gmail.com>: > That's the trivial solution with quite a few copies and transfers involved. > But if the Umat is used with OpenCL, the image data should reside on the > GPU already, which means you don't need to download it from the gpu and > upload it back again for displaying the data. > But that means, it must be possible to create a UMat from an OpenCL > buffer, as it must be created first via OpenGL (silly restriction for the > OpenCL OpenGL interoperability). > If that works, one can manipulate the Umat via OpenCL and the OpenGL > buffer will be the same memory and can be displayed without any copies ;) > > > 2014-12-08 15:43 GMT+01:00 Max Suster <mxsst...@gmail.com>: > >> >>> http://stackoverflow.com/questions/9097756/converting-data-from-glreadpixels-to-opencvmat >> >> >> Seem that the link above shows a solution to this. >> >> Max >> >> On Monday, December 8, 2014 3:02:25 PM UTC+1, Simon Danisch wrote: >>> >>> That's really great! I will have to investigate, how to convert between >>> OpenGL datatypes and UMat. >>> It would be incredible, if we can convert between julia, opencl, opengl >>> and opencv datatypes without a big overhead. >>> I'm pretty sure, that no other language has this solved nicely! ;) >>> >>> Am Samstag, 6. Dezember 2014 11:44:45 UTC+1 schrieb Max Suster: >>>> >>>> >>>> Hi all, >>>> >>>> A few months ago I set out to learn Julia in an attempt to find an >>>> alternative to MATLAB for developing computer vision applications. >>>> Given the interest (1 >>>> <https://groups.google.com/forum/#!searchin/julia-users/OpenCV/julia-users/PjyfzxPt8Gk/SuwKtjTd9j4J> >>>> ,2 >>>> <https://groups.google.com/forum/#!searchin/julia-users/OpenCV/julia-users/81V5zSNJY3Q/DRUT0dR2qhQJ> >>>> ,3 >>>> <https://groups.google.com/forum/%23!searchin/julia-users/OpenCV/julia-users/iUPqo8drYek/pUeHECk91AQJ> >>>> ,4 >>>> <https://groups.google.com/forum/%23!searchin/julia-users/OpenCV/julia-users/6QunG66MfNs/C63pDfI-EMAJ> >>>> ) and wide application of OpenCV for fast real-time computer vision >>>> applications, I set myself to put together a simple interface for OpenCV in >>>> Julia. Coding in Julia and developing the interface between C++ and >>>> Julia has been a lot of fun! >>>> >>>> OpenCV.jl aims to provide an interface for OpenCV <http://opencv.org/> >>>> computer >>>> vision applications (C++) directly in Julia >>>> <http://julia.readthedocs.org/en/latest/manual/>. It relies primarily >>>> on Keno´s amazing Cxx.jl <https://github.com/Keno/Cxx.jl>, the Julia >>>> C++ foreign function interface (FFI). You can find all the information on >>>> my package at https://github.com/maxruby/OpenCV.jl. >>>> >>>> You can download and run the package as follows: >>>> >>>> Pkg.clone("git://github.com/maxruby/OpenCV.jl.git")using OpenCV >>>> >>>> >>>> For MacOSX, OpenCV.jl comes with pre-compiled shared libraries, so it >>>> is extremely easy to run. For Windows and Linux, you will need to first >>>> compile the OpenCV libraries, but this is well documented and links to the >>>> instructions for doing so are included in the README.md file. >>>> >>>> The package currently supports most of OpenCV´s C++ API; however, at >>>> this point I have created custom wrappings for core, imgproc, videoio >>>> and highgui modules so that these are easy to use for anyone. >>>> >>>> The package also demonstrates/contains >>>> >>>> - preliminary interface with the Qt GUI framework (see imread() and >>>> imwrite() functions) >>>> - thin-wrappers for C++ objects such as std::vectors, std::strings >>>> - conversion from Julia arrays to C++ std::vector >>>> - conversion of Julia images (Images.jl) to Mat (OpenCV) - though >>>> this has much room for improvement (i.e., color handling) >>>> >>>> Please let me know if there are any features you would like to see >>>> added and I will try my best to integrate them. In the meantime, I will >>>> continue to integrate more advanced algorithms for computer vision and >>>> eventually extend the documentation as needed. >>>> >>>> Cheers, >>>> Max >>>> >>>> >>>> >>>> >>>> >>>> >
