Sunday, September 30, 2012

Convert files to .mp4 format - Python Script

We all download videos of our favorite songs, animation, tutorials, movie, dramas from like's of youtube,, vimeo etc.This artical is not about how to download these files, I'll reserve that for later. What I am going to tell you is something more intriguing.

Today is the world of gadgets. Our houses have variety of gadgets like iPhone, iPad, iPod, Android music players, Android phones, W8 laptops/tablets (& sometimes) W8 phones too. If you download video from any of these websites the format of the downloaed file is inconsistent. It can be mp4, avi, webm, flv...etc. Give the diversity of devices, it makes sense to have files in one format so as to maintain some consistency in the apps we downoad and use.

ffmpeg is an excellent utility for such conversions. You can install it with the command
sudo apt-get install ffmpeg

To convert (say) .webm file to .mp4
ffmpeg -i some_file.webm my_fav_file.mp4

That was easy, wasn't it? Yep it is. But imagine if you have to convert an entire collection of files. That will be an arduous task. Won't it be better if we could write a simple utility that will convert all files in a directory. Yep, that's where I am heading to. Here's a simple script that will convert .webm files to .mp4. You can easily customize it to convert any other file to .mp4, if you want to

#!/usr/bin/env python
# -*- coding: utf-8 -*-

#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.

#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  GNU General Public License for more details.

#  You should have received a copy of the GNU General Public License
#  along with this program; if not, write to the Free Software
#  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
#  MA 02110-1301, USA.

import glob
import os
from optparse import OptionParser

class ConvertToMP4:
    def __init__(self):
        self.webmFiles = []
    def get_all_wbm_files_from_directory(self, directory_name):
        print("Scanning directory: " + directory_name)
        if len(directory_name) == 0:
            print('ERROR: Source directory name cannot be NIL/NULL.')
            print('Provide a valid directory name to proceed!')
        for files in os.listdir('.'):
            if files.endswith('.webm'):
                print('convert file: ' + files)

    def convert_wbm_file_to_mp4_file(self):
        # check to see if the list is empty, if not proceed
        if len(self.webmFiles) <= 0:
            print("No files to convert!")
        for webm_file in self.webmFiles:
            mp4_file = webm_file.replace('.webm','.mp4')
            cmd_string = 'ffmpeg -i "' + webm_file + '" "' + mp4_file + '"'
            print('converting ' + webm_file + ' to ' + mp4_file)

def main():
    usage = "usage: %prog -d <source directory for webm files>"
    parser = OptionParser(usage=usage)
    parser.add_option("-d", "--sourcedirectory", action="store",
        type="string", dest="sourcedirectory", default="./",
          help="source directory where all the webm files are stored!")
    (options, args) = parser.parse_args()
    webm_to_mp4 = ConvertToMP4()
    return 0

if __name__ == '__main__':

Even better, if you can provide a link to the utility and the utility download's it for you in mp4 format. That will be my next area of work

Audio issues in Ubuntu

I had some issues with the audio controls in my machine. I was not able to figure out what was going on. However after a restart things were back to normal. I was not able to figure out what was going on. The same thing happened one more time logs did not have much information either or may be I was not looking at the right places. However after witnessing this a couple of times, I noticed this was more a sound card issue

Here are some commands that helped me

Open Terminal and type the following command 'alsamixer'
You will be shown the sound card configuration, follow the help, re-configure  and your sound card will be back in action

Alternatively you can use pavucontrol too
sudo apt-get install pavucontrol

Pavucontrol widget makes it easy for you to setup and identify issues like this. Add it to startup application if needed (especially if you are using old computers)