OpenCV 3.0.0 stitching using GPU

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I am trying to stitch multiple images using OpenCV 3.0.0. This works fine when the try_gpu flag is set to false. However, when I set it to true, I get the following run-time error

You should explicitly call download method for gpu::GpuMat object

Following this, I changed my Mat declarations to GpuMat (using upload function), set my try_gpu flag to true. This time, I get the error

OpenCV Error : Assertion failed in cv::resize, file ......\opencv\modules\imgproc\src\imgwarp.cpp, line 2350

I haven't been able to find any resource online which explicitly states how to use the GPU flag for stitching