Put ssd300_mAP_77.42_v2.pth in this folder. Download it here, more information here.
If you follow along with the Computer Vision A-Z course on Udemy, the API changes in PyTorch 0.4.0 break some of the magic happening in the provided SSD code. I managed to get some detection going on by lowering the detection score threshold, but that didn't really let me recognize the dog:
