sabooky

#!/usr/bin/pythonimport sysimport osimport globimport subprocessimport rere_xvidpsnr=re.compile("xvid: Average.*All:(.*?) ")re_x264psnr=re.compile("x264 \[info\]: PSNR Mean.*Global:(.*?) ")def getvidinfo(vidfile):	"""returns the vid total frames (len,frames)"""	p=subprocess.Popen(["mplayer","-vo", "null", "-identify",vidfile], \			stderr=subprocess.PIPE, \			stdout=subprocess.PIPE, \			stdin=subprocess.PIPE).communicate('q')[0]	for line in p.split('\n'):		if line.startswith("ID_LENGTH="):			length=float(line.split("=")[1])		if line.startswith("ID_VIDEO_FPS"):			fps=float(line.split("=")[1])	frames=int(length*fps)	return length,framesdef getpsnr(vidfile, format, mplayeropts, fq):	"""Return the average psnr"""	length,frames=getvidinfo(vidfile)	frames_to_process=frames*.02	no_of_segments = 20	if frames_to_process<3000:		frames_to_process = 3000	fpseg=int(frames_to_process/no_of_segments)	segs=range(0,int(length),int(length/no_of_segments))[1:-1]	quant_opt = "-xvidencopts"	quant_string = "fixed_quant"	if format=="x264":		quant_opt = "-x264encopts"		quant_string = "crf"	psnrs=[]	bitrates=[]	program = ["mencoder"]	quant = [quant_opt, "%s=%s:psnr"%(quant_string,fq)]	options = ["-forceidx","-nosound"]+mplayeropts+quant+["-frames",str(fpseg)]	outfile = ["-o","/dev/null"]	for seg in segs:		ss=["-ss",str(seg)]		runlist=program+options+ss+[vidfile]+outfile		p=subprocess.Popen(runlist,stderr=subprocess.PIPE, stdout=subprocess.PIPE)		output=p.communicate()#		print output[1]#		print runlist		if format=="xvid":			psnr=float(re_xvidpsnr.search(output[0]).group(1))		elif format=="x264":			psnr=float(re_x264psnr.search(output[1]).group(1))		bitrate=float([i.split()[2] for i in output[0].split('\n') if i.startswith('Video stream:')][0])		bitrates.append(bitrate)		psnrs.append(psnr)		sys.stdout.write("%s..."%psnr)		sys.stdout.flush()	average_psnr = sum(psnrs)/len(psnrs)	average_bitrate = sum(bitrates)/len(bitrates)	print	print '%s: %.1f' %(quant_string, fq)	print 'avg psnr:',average_psnr	print 'avg bitrate:', average_bitrate	return average_psnr	def processvid(vidfile,targetpsnr, format, mplayeropts, ask=True):	"""Return the average psnr for these segments"""	fq=2.0	variance=2	quant_string="fixed_quant"	if format=="x264":		fq=18		variance*=2		quant_string="crf"	targetpsnr=float(targetpsnr)	print "Pass (1/2):"	firstpsnr = getpsnr(vidfile, format, mplayeropts, fq)	print "\nPass (2/2):"	secondpsnr = getpsnr(vidfile, format, mplayeropts,  fq+variance)	guessfq = fq+(abs(firstpsnr-targetpsnr)/((firstpsnr-secondpsnr)/variance))	print	print "%s: %.1f\nShould yield\nPSNR guess:%.3f"%(quant_string, guessfq, targetpsnr)	if ask:		print		reply = raw_input('Would you like to test for bitrate (this will do another pass)? [Y/n]: ')		if reply=='' or reply.lower()=='y':			thirdpsnr = getpsnr(vidfile, format, mplayeropts, guessfq)	else:		thirdpsnr = getpsnr(vidfile, format, mplayeropts, guessfq)def getoptions():	"""gets the options from user input"""	if len(sys.argv)<5:		print """usage: %s [MENCODER OPTIONS] [FILE] [PSNR]	MENCODER OPTIONS = options excluding -o, crf, fixed_quant, and bitrate			     -profile is allowed	PSNR             = target psnrexample: %s -ovc xvid -xvidencopts chroma_opt:threads=2:autoaspect title1.vob 44"""\		%(os.path.basename(sys.argv[0]), os.path.basename(sys.argv[0]))		sys.exit()	targetpsnr = sys.argv[-1]	vidfile = sys.argv[-2]	mplayeropts = sys.argv[1:-2]	#check for -ovc to find out what codec user is using	if "-ovc" in mplayeropts:		format = mplayeropts[mplayeropts.index("-ovc")+1]		if not (format=="xvid" or format=="x264"):			print "%s codec not supported by %s"%(format,os.path.basename(sys.argv[0]))			sys.exit()	#check if -profile is one of the options	elif "-profile" in mplayeropts:		profile = mplayeropts[mplayeropts.index("-profile")+1]		for i in subprocess.Popen(("mencoder -show-profile %s"%profile).split(), \				stdout=subprocess.PIPE).stdout:			if i.strip().startswith("ovc="):				format=i.split('=')[1]				if not (format=="xvid" or format=="x264"):					print "%s codec not supported by %s" % \							(format, os.path.basename(sys.argv[0]))					sys.exit()				break	else:		print "no -profile or -ovc option present"		sys.exit()	return vidfile, targetpsnr, format, mplayeropts(vidfile, targetpsnr, format, mplayeropts) = getoptions()processvid(vidfile,targetpsnr, format, mplayeropts)for x in glob.glob('psnr*.log'):	os.unlink(x)