mae = 0
for i in tqdm(range(len(img_paths))):
    img = transform(Image.open(img_paths[i]).convert('RGB')).cuda()
    gt_file = h5py.File(img_paths[i].replace('.jpg','.h5').replace('images','ground-truth'),'r')
    groundtruth = np.asarray(gt_file['density'])
    output = model(img.unsqueeze(0))
    mae += abs(output.detach().cpu().sum().numpy()-np.sum(groundtruth))
print (mae/len(img_paths))