I capture 3-video from 3 usb camera,and encode each of them to format h264, then save to the sd card,I want to get video processing capacity of imx6 or imx8. I know imx6,totall encoding frame rate is 720@60fps, so if 3-video from 3 usb camera, the frame rate of encoding each stream is 2*30fps/3=20fps?