The trained model has very low accuracy

[ting3000]

I run the training with 1,000,000 iterations, then copied the caffemodel file to openpose/models/pose/body_25 to replace the pose_iter_584000.caffemodel file, then run
./build/examples/openpose/openpose.bin --video examples/media/video.avi
The result is very poor and it hardly detects any body part.
What did I do wrong?
What is the right way to evaluate the trained model?
Do I need iterate more training?

Thanks,