For object detection, you can use ssd, yolov3 etc. These are links for object detection using pytorch 

  
      
      GitHub
  
  
    

amrit-das/pytorch_ssd 98

Pytorch Implemetation of Single Shot Detector (SSD) - amrit-das/pytorch_ssd


  
  
    
    
  
  



  
      
      GitHub
  
  
    

amrit-das/yolov3_pytorch 69

Realtime object detection using yolov3 implemented in PyTorch - amrit-das/yolov3_pytorch


  
  
    
    
  
  


For custom object detection using your own dataset look for these repository 

  
      
      GitHub
  
  
    

michhar/pytorch-yolo-v3-custom 85

A PyTorch implementation of the YOLO v3 object detection algorithm for training on custom data with video demo. - michhar/pytorch-yolo-v3-custom