Normalize media files using Python and FFMpeg

normalize.py

#! /usr/bin/python

import getopt, sys, os, time, subprocess, shutil, argparse

WIDTH = 1280
HEIGHT = 720
RATE = "60000/1001"
EXT = ".mov"
FFMPEG = "ffmpeg.exe"

description = (
    "Normalize files\n"
    "   Input and output may be specified as either a file or directory.            \n"
    "   * If input is a file, it will be normalized to the output file.             \n"
    "   * If input is a directory, all files inside the directory will be           \n"
    "     normalized and stored in the output directory.                            \n"
    "   In all cases, an appropriate file extension is added.                       \n"
)
parser = argparse.ArgumentParser(description=description)
parser.add_argument("-t", help="Rename output files with modification [t]ime", action='store_true')
parser.add_argument("src")
parser.add_argument("dst")
args = parser.parse_args()

def get_destination_filename(srcname):
    dstname = ""

    if args.t:
        dstname = time.strftime("%Y-%m-%d-%H%M%S", time.gmtime(os.path.getmtime(srcname)) )
    else:
        # Strip the path and extension
        dstname = os.path.basename( os.path.splitext(srcname) )
        # Clean the name of spaces and strange characters
        dstname.replace(" ", "")
        ''.join(e for e in dstname if e not in "{}()![],")

    return dstname + EXT

def normalize_file(src_file, dst_file):
    print("Normalize", srcfile, "to", dstfile)

    # Get information about the video
    infocmd = [ FFMPEG,
                '-i',
                src_file,
                '-vframes', '1',
                "-vf", 'showinfo',
                '-an',
                '-f', 'rawvideo',
                '-y',
                os.devnull
              ]
    procinfo = subprocess.run(infocmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, universal_newlines=True)
    vidinfo = ""
    for line in procinfo.stdout.split("\n"):
        if "showinfo" in line:
              vidinfo = line
    # Structure is printed as i:T or i:B or i:P
    structure = vidinfo.split("i:")[1].split()[0]
    # Size is printed as s:1920x1080
    iw = vidinfo.split(" s:")[1].split()[0].split("x")[0]
    ih = vidinfo.split(" s:")[1].split()[0].split("x")[1]

    filters = ""
    # Deinterlace if necessary
    if structure != "P":
        print("Source is Interlaced")
        # Duplicate frames
        filters = filters + "yadif=1:-1:0"
    else:
        print("Source is Progressive")

    # Scale if necessary
    if iw != WIDTH or ih != HEIGHT:
        print( "Scale", iw, "x", ih, "->", WIDTH, "x", HEIGHT)
        if filters != "":
             filters += ","
        filters += "scale=(iw*sar)*min({WIDTH}/(iw*sar)\,{HEIGHT}/ih):ih*min({WIDTH}/(iw*sar)\,{HEIGHT}/ih)".format(WIDTH=WIDTH, HEIGHT=HEIGHT)
        filters += ","
        # Add bars if AR does not match. Has no effect when they do match.
        filters += "pad={WIDTH}:{HEIGHT}:({WIDTH}-iw*min({WIDTH}/iw\,{HEIGHT}/ih))/2:({HEIGHT}-ih*min({WIDTH}/iw\,{HEIGHT}/ih))/2".format(WIDTH=WIDTH, HEIGHT=HEIGHT)

    cmd = [ FFMPEG,
            '-i',
            src_file,
            '-sn',
          ]

    if filters:
        cmd += ["-vf", filters]
          
    cmd += [
            '-r', RATE,
            '-vcodec', 'dnxhd',
            '-vb', '220000k',
            '-pix_fmt', 'yuv422p',
            '-threads', '3',
            '-acodec', 'pcm_s16le',
            '-ac', '2',
            '-ar', '48000',
            dst_file
          ]
    
    print( "About to run command:" )
    print(cmd)

    subprocess.run(cmd)

    # Make sure the normalize succeeded.
    if os.path.isfile(dst_file):
        shutil.copystat( src_file, dst_file )
    else:
       print("Normalize Failed")
       exit( 7 )

# Sanity checking, to make sure everything is in order.
if os.path.isfile(args.src):
    # Normalize a single file
    srcfile = args.src
    dstfile = get_destination_filename(srcfile)
    normalize_file( srcfile, dstfile )
elif os.path.isdir(args.src):
    if not os.path.isdir(args.dst):
        print(args.src, "is a directory but", args.dst, "is not a directory")
        exit(1)

    for file in os.listdir(args.src):
        srcfile = os.path.join(args.src, file)
        dstfile = os.path.join(args.dst, get_destination_filename(srcfile))
        normalize_file( srcfile, dstfile )
else:
    print( args.src, "is not a file or directory" )
    exit(2)