Python script to convert any video file into a number of other kind of files: DIVX-compatible file no more than 640x480 in size, MP4 that works with the original iPhone/iPod no more than 480x320 in size, and MP4 that works with the Kindle Fire HD no more than 1280x800 in size. You can hardcode subtitles if you want. Limitations: ffmpeg v1 is req…

convert_to_divx.py

#!/usr/local/bin/python
# convert any video file recognized by ffmpeg to divx
import subprocess, json, argparse, tempfile, os
import pprint

# Check arguments
parser = argparse.ArgumentParser(description="Convert any video file recognized by ffmpeg into a legacy DIVX")
parser.add_argument('--iphone',help='Convert to iPhone-compatible mp4 instead of Divx',action='store_true')
parser.add_argument('--kindlefirehd', help='Convert to Kindle Fire compatible mp4 instead of Divx', action='store_true')
parser.add_argument('--subtitles', help='Name of subtitles file to burn into video.')
parser.add_argument('input_file')
parser.add_argument('output_file')
args = parser.parse_args()
pprint.pprint(args)
ffprobe_loc = '/usr/local/bin/ffprobe1'
ffmpeg_loc = '/usr/local/bin/ffmpeg1'
#file_to_convert = '/Volumes/Downloads/A.Hard.Days.Night.1964.720p.BluRay.x264-CiNEFiLE/a.hard.days.night.1964.720p.bluray.x264.sample-cinefile.mkv'
# for now, make some assumptions about desired divx
#ok_audio_formats = ['mp3', 'aac']
mp4_video_args = ['-c:v', 'libx264', '-preset:v', 'slow', '-crf:v', '23', '-profile:v', 'baseline']
mp4_audio_args = ['-c:a', 'libfdk_aac', '-ac', '2', '-vbr', '3']
if args.iphone == True:
  max_width = 480
  max_height = 320
  video_args = mp4_video_args
  audio_args = mp4_audio_args
elif args.kindlefirehd == True:
  max_width = 1280
  max_height = 800
  video_args = mp4_video_args
  audio_args = mp4_audio_args
else:
  max_width = 640
  max_height = 480
  video_args = ['-c:v', 'mpeg4', '-q:v', '4', '-tag:v', 'DIVX' ]
  audio_args = ['-c:a', 'libmp3lame', '-q:a', '5', '-ac', '2', '-ar', '44100']

if args.subtitles != None:
  # get a temp location for the subtitle file
  sub_file = tempfile.NamedTemporaryFile(delete=False,suffix='.ass')
  sub_filename = sub_file.name
  sub_file.close()
  subprocess.call([ffmpeg_loc,'-y', '-i', args.subtitles, sub_filename])
  video_args = video_args + ['-vf:v', 'ass='+sub_filename]

# get current info
file_info = subprocess.check_output([ffprobe_loc,'-v','quiet', '-print_format', 'json', '-show_format', '-show_streams' ,args.input_file])
j_file_info = json.loads(file_info)
# for now, just force the audio to mp3
video_exists = False
audio_exists = False

for this_stream in j_file_info['streams']:
  print this_stream['codec_type']
  print this_stream['codec_name']
  if this_stream['codec_type'] == 'audio':
    if 'tags' in this_stream and 'language' in this_stream['tags'] and this_stream['tags']['language'] == 'eng':
      if audio_exists:
        print 'error: more than one English audio stream not supported'
        exit()
      audio_exists = True
      audio_index = this_stream['index']
      print 'english audio stream detected'
  if this_stream['codec_type'] == 'video':
    if video_exists:
      print 'error: more than one video stream not supported'
      exit()
    video_exists = True
    video_index = this_stream['index']
    print 'video stream detected'
    # first limit the video size, if necessary
    width_ratio = float(max_width) / float(this_stream['width'])
    height_ratio = float(max_height) / float(this_stream['height'])
    if width_ratio < 1 or height_ratio < 1:
      if width_ratio >= height_ratio:
        # limit based on height
        print 'limiting height of %s to %s' % (this_stream['height'], max_height)
        new_width = this_stream['width'] * height_ratio
        new_height = this_stream['height'] * height_ratio
      else:
        # limit based on width
        print 'limiting width of %s to %s' % (this_stream['width'], max_width)
        new_width = this_stream['width'] * width_ratio
        new_height = this_stream['height'] * width_ratio
      print 'new width: %s  new height: %s' % (new_width, new_height)
      new_width = int(16 * ((new_width + 8) // 16))
      new_height = int(16 * ((new_height + 8) // 16))
      print 'rounded to closest 16: %sx%s' % (new_width, new_height)
      video_args = video_args + ['-s','%sx%s' % (new_width, new_height)]
      
# if the audio and video streams are known, do the mapping. Otherwise just leave it to fate
if video_exists and audio_exists:
  mapping_args = ['-map','0:%i' % video_index,'-map','0:%i' % audio_index]
else:
  mapping_args = []
pprint.pprint(mapping_args)
pprint.pprint(audio_args)
pprint.pprint(video_args)

subprocess.call([ffmpeg_loc,'-i', args.input_file] + mapping_args + video_args + audio_args + [args.output_file])  
if args.subtitles != None:
  os.remove(sub_filename)