Solved by gb_pytorch in post #4 
              
              
                I figured out the solution. This worked for me though I had to display masks in different figures. 
    visualize(
        image=denormalize(image_vis.squeeze()),
        gt_mask_car=gt_mask[0].squeeze(),
        pr_mask_car=pr_mask[0].squeeze(),
        gt_mask_pedestrian=gt_mask[1].squeeze(),
    …