def _get_duration(filename) :
    command = ['ffprobe',
               '-v', 'error',
               '-show_entries', 'format=duration',
               '-of', 'default=noprint_wrappers=1:nokey=1',
               filename, '-sexagesimal']
    ffmpeg = subprocess.Popen(command, stderr=subprocess.PIPE ,stdout = subprocess.PIPE )
    out, err = ffmpeg.communicate()
    if(err) : print(err)
    return out

def _read_frame(filename,time) :
    command = ['ffmpeg',
               '-loglevel', 'error',
               '-ss', str(time), #from this time
               '-i', filename,
               '-vframes', str(1),          #get single frame
               '-f', 'image2pipe',
               '-pix_fmt', 'rgb24',
               '-vcodec', 'rawvideo', '-']
    #print(command)
    ffmpeg = subprocess.Popen(command, stderr=subprocess.PIPE ,stdout = subprocess.PIPE )
    out, err = ffmpeg.communicate()
    if(err) : print(err)
    image =  np.fromstring(out, dtype='uint8').reshape((960,1280,3))
    return image