this is the way i use the dataparallel function, 
2019-04-28 10-10-29屏幕截图.png734×57 8.83 KB
 ,i am sure there were 2 gpus working when i run the code, and it works with one gpu, when i use large image ,one gpu is out of memory ,so i want to use 2 gpu,but the generated image became deteriorated ,i don not know why?