@dancedpipi What was your ultimate result?  Were  you able to fix your problem?
@dambo Am I also misunderstanding the from_blob?  I was also under the impression that using the GpuMat should be more efficient than Mat when dealing with large datasets because you are avoiding Cpu to Gpu copies?  Am I incorrect here?  Would from_blob perform a copy within the GPU or would it change the way the data is referenced?