change detection with CNN pytorch

I want to display a change detection image after the result of the confusion matrix, I have divided my model 70% train and 30% test.

print('Validation accuracy test: {:.4f}%'.format(float(accuracy_score(val_y, predictions)) * 100))
conf_matrix  = confusion_matrix(val_y, predictions)
for i in range(predictions.size) : 
    x = val_x[i]
    y=predictions[i]

plt.imshow(x,y)