wpf - Best way to display progress of wave file playback on waveform -

i have program plays mp4 video , uses video's audio track plot waveform. how best denote progress of waveform plot( there 2 samples per second) remains in sync video?

i waveform , whatever use denote current time on waveform plot remain in sync video playing using timeline , media clock have implemented.

other programs denote shading area has been played, or keeping bar waveform moves across bar denotes current time. need in deciding implement , begin in implementation.

if not clear, happy clarify question, let me know.

i coding in c#, on wpf program, using naudio well.

well it's think looks best. easier 1 implement cursor on top of waveform, since can move playing.

if want shade in part of waveform, depends on how implemented waveform drawing. if based on series of vertical lines, can change colour of lines before playing time. if you'd constructed waveform polygon harder. there clever tricks use such drawing rectangle , telling wpf clip according waveform, you'll find easier use vertical line drawing approach.