DNN using multiple images works with tensorflow models but fail with darknet models

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OpenCV => :3.4.5 Operating System / Platform => windows 7 windows 10: Compiler => :microsoft vs2019: C++ Detailed description I am working on license plate detection. I have 2 models: 1 ssd mobilenet 2 darknet tiny yolo v3. Both works fine with opencv inference when using one image as input to blobFromImages. When I add second image to the matrices vector: The tensorflow model postprocessing works fine while the darknet fail. In the sample postprocessing code of darknet models the results depends on output[i].rows and cols. When entering 2 images the returned outputs[i].rows and cols equal -1. If this is ok than how do I extract the results from the output matrices. With tensorflow model the output matrix rows and cols is always -1 but extracting the results does not depand on these.