Gstreamer cmdline

gst-launch-1.0 multifilesrc location=pic%05d.jpg start-index=28600 stop-index=28699 ! image/jpeg,framerate=10/1 ! jpegparse ! nvv4l2decoder ! nvv4l2h264enc ! h264parse ! qtmux ! filesink location=yyy.mp4 sync=true
The yyy.mp4`s frmaes is samel;but jpgs is not same; how to fix cmd