Attain FFMPEG progress via regex

pyFfmpegProgress.py

#store track duration in seconds
duration_flt = -1

#read each line of output from FFMPEG popen object
for line in output:    
    #no duration yet
    if duration_flt == -1:
        #get duration via regex match
        dur_patern = re.compile("Duration: [0-9]{2}:[0-9]{2}:[0-9]{2}.[0-9]{2}")
        dur_matches = dur_patern.findall(line)
        if duration_flt == -1 and len(dur_matches) > 0:
            #store duration as seconds
            duration_flt = str_to_secs(dur_matches[0])

    #duration found, get current time position of encode
    else:
        #get current time via regex match
        time_pattern = re.compile("time=[0-9]{2}:[0-9]{2}:[0-9]{2}.[0-9]{2}")
        time_matches = time_pattern.findall(line)
        if len(time_matches) > 0:
            #store current encode point as seconds
            last_time_match = str_to_secs(time_matches[0])

            #get percentage complete
            progress = 100 * (float(last_time_match)/duration_flt)
 
def str_to_secs(input):
    text = re.compile("[0-9]{2}:[0-9]{2}:[0-9]{2}.[0-9]{2}").findall(input)[-1]
    blocks = re.compile("[0-9]{2}").findall(text)
    h = int(blocks[0])
    m = int(blocks[1])
    s = int(blocks[2])
    ms = int(blocks[3])
    return h*60*60 + m*60 + s + ms*0.1

I have done similar work, made it in a js module here.