mythtv hdpvr colorfixer

#!/usr/bin/env python

import os
import time
import sys
import glob
import subprocess

def fix_color():
    fix_string=("/usr/bin/v4l2-ctl --device=%s "+
                "--set-ctrl brightness=0x80 --set-ctrl contrast=0x40 "+
                "--set-ctrl hue=0xf --set-ctrl saturation=0x40 "+
                "--set-ctrl sharpness=0x80")
    for device in glob.glob("/dev/hdpvr*"):
        command=fix_string % device
        subprocess.call(command,shell=True)

def daemonize():
    try:
        pid = os.fork()
        if pid > 0:
            sys.exit(0)
    except OSError as ose:
        sys.stderr.write("fork failed: %d (%s)\n" % (ose.errno,ose.strerror))
        sys.exit(1)
    os.chdir("/")
    os.setsid()
    os.umask(0)

    try:
        pid = os.fork()
        if pid > 0:
            sys.exit(0)
    except OSError as ose:
        sys.stderr.write("fork failed: %d (%s)\n" % (ose.errno,ose.strerror))
        sys.exit(1)

    sys.stdout.flush()
    sys.stderr.flush()
    si = file('/dev/null', 'r')
    #so = file('/dev/null', 'a+')
    #se = file('/dev/null', 'a+',0)

    os.dup2(si.fileno(),sys.stdin.fileno())
    #os.dup2(so.fileno(),sys.stdout.fileno())
    #os.dup2(se.fileno(),sys.stderr.fileno())

    return os.getpid()

def main():
    daemonize()
    time.sleep(2)
    for i in range(0,2):
        fix_color()
        time.sleep(1)

if __name__=="__main__":
    main()