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Just Upgraded my Nexus One from Android 2.1 to Android 2.2

The latest Android OS version 2.2 (”Froyo”) was announced at the Google I/O conference on the 11th of May. As you already probably know it adds multiple enhancements like tethering, wifi hotspot functionality, full support for Flash, etc. Since I use my Nexus One phone for Android development, I did not want to download the update from Google and then install it with adb. I just wanted to wait for the over the air update.

And to my surprise, the first time I looked at my phone this morning, I had this message on the screen:

Android 2.2 Upgrade Message

I was not sure how long it would take, so I just hit “Install Later”. Then a couple of hours later, when I was ready, I just went to Settings -> About Phone -> Software Update and hit “Restart & Install”:

Android 2.2 Settings -> About Phone -> System Updates

The phone rebooted and started the upgrade. The whole process with the installation took less than 5 minutes.

I am not going to go into details what the features of Android 2.2 are. There are so many announcements and blog posts on this matter already out there…

But what I am going to say is that Android is the leading OS in the mobile phone market right now. I can say this definitively, since I have been using iPhones for the past 2 years. I have a 3G and a 3GS phones. I encourage any iPhone user to go and check out an Android device. Please do not look at the low end hardware that runs Android (like the Cliq, the old G1, etc.). Check out the HTC Evo, the HTC Incredible, the Nexus One etc. See for yourselves before you make your decision to get another phone and lock into a 2 year contract. I will mention only a few things you will discover on the Android device that your phone probably does not have right now:

1. Turn by turn voice navigation
2. Built in tethering
3. Built in WiFi hotspot capability supporting multiple devices
4. Full support for Flash
5. Full blown multitasking on the OS level (no need for the programmer to do anything special)
6. Integrated speech recognition across the board. Voice input could be used anywhere in place of the text input.
7. Over the air updates and syncing. That means no iTunes or the like!

And many other features that I do not want to get into details right now. I am sure you can fill in the gaps for yourselves…

Find the Geopgraphical Location of an IP Address

There are a few applications that give the geographical location of an IP address *. My favorite one is VisualRoute. It not only maps the location of the source and destination IP addresses, but also all the hops in between. The down side to it is that it is not available for Linux and it costs $50 per user.

The http://mapulator.com site gives you pretty much the same information online for free, but it has been down for quite some time now.

Lately I have been using http://whatismyipaddress.com/ip-lookup. But it only maps the destination IP address.

If anyone knows of a Linux application that would map all the hops and the final IP destination, please leave a comment!

* IP addresses do not have a geographical location per se. Any program that maps IP addresses can only give you where the whole class of IP addresses (that the specified IP address belongs to) is registered to be located at. They do this by querying a database that has that information. This is accurate down to a city level at best. Do not expect to find where someone lives by their IP address!

Install Subversion and Subclipse for Eclipse on Ubuntu

If you do not have Eclipse installed yet, run:

sudo apt-get install eclipse

Install Subversion

sudo apt-get install subversion

Install the Subversion plugin for Eclipse

Get the Java bindings for Subversion:

sudo apt-get install libsvn-java

Now we are ready to install the plugins in Eclipse.

Open Eclipse.

Go to Help -> Install New Software

Then hit the “Add” button.

Put “Subclipse 1.6.x (Eclipse 3.2+)” under Name and “http://subclipse.tigris.org/update_1.6.x” under Location:

Add the libraries for Subclipse

The above is for Elclips 3.2+ and Subversion 1.6.x.

If you have different Eclipse or Subversion versions, check this list and substitute accordingly:

Name: Subclipse 1.6.x (Eclipse 3.2+)
URL: http://subclipse.tigris.org/update_1.6.x

Name: Subclipse 1.0.x (Eclipse 3.0/3.1)
URL: http://subclipse.tigris.org/update_1.0.x

More info about the different versions: http://subclipse.tigris.org/servlets/ProjectProcess?pageID=p4wYuA

Then hit “OK”. You will now be presented with these options:

Subclipse Installation Options

If you are unsure what Subclipse component you will need, you can check all of them. Also, keep in mind that you can always go back to this in the future and install/uninstall any of the components as needed.

Then “Next” and “Finish” on the subsequent screens.

After the plugins are installed, it will prompt you to restart Eclipse. Go ahead and do so.

You are not done yet. You need to fix the JavaHL.

Edit the eclipse.ini file:

sudo vi /usr/lib/eclipse/eclipse.ini

Add the following line under -vmargs:

-Djava.library.path=/usr/lib/jni

Here is what my eclipse.ini file looks like:

$ cat /usr/lib/eclipse/eclipse.ini
-startup
plugins/org.eclipse.equinox.launcher_1.0.201.R35x_v20090715.jar
--launcher.library
plugins/org.eclipse.equinox.launcher.gtk.linux.x86_1.0.200.v20090520
-showsplash
org.eclipse.platform
--launcher.XXMaxPermSize
256m
-startup
--launcher.library
-showsplash
org.eclipse.platform
--launcher.XXMaxPermSize
256m
-startup
/usr/lib/eclipse/plugins/org.eclipse.equinox.launcher_1.0.201.R35x_v20090715.jar
--launcher.library
/usr/lib/eclipse/plugins/org.eclipse.equinox.launcher.gtk.linux.x86_1.0.200.v20090520
-vmargs
-Djava.library.path=/usr/lib/jni
-Dorg.eclipse.equinox.p2.reconciler.dropins.directory=//usr/share/eclipse/dropins
-Xms40m
-Xmx256m
-Dorg.eclipse.equinox.p2.reconciler.dropins.directory=//usr/share/eclipse/dropins

For more info on fixing JavaHL if you need it: http://subclipse.tigris.org/wiki/JavaHL#head-bb1dd50f9ec2f0d8c32246430c00e237d27a04fe

You should be able to use Subversion with Eclipse for your projects at this point.

Extract Audio (.mp3) from Video Files Like .flv, .mov, .avi and Others with Ubuntu

It is very easy to extract the audio track from video files using Linux. All you need is ffmpeg and some codecs.

Let’s get started…

Note: The commands below are for Ubuntu (or Debian derivatives) but you can do the same with any other Linux distribution provided you can install the necessary packages.

1. Add the Medibuntu’s repository to your sources.list:

sudo wget --output-document=/etc/apt/sources.list.d/medibuntu.list http://www.medibuntu.org/sources.list.d/$(lsb_release -cs).list && sudo apt-get --quiet update && sudo apt-get --yes --quiet --allow-unauthenticated install medibuntu-keyring && sudo apt-get --quiet update

2. Install ffmpeg:

sudo apt-get install ffmpeg

3. Let’s get the restricted packages and some codecs installed:

sudo apt-get install ubuntu-restricted-extras libmp3lame0 libdvdcss2 w32codecs

The above command is for i386 architecture. If you have an amd64 architecture, substitute w32codecs with w64codecs.

Note: This is not a complete list of codec packages by any stretch of the imagination. It will get you started though and you will be able to do most formats, but you might have to add codecs as you go along.

4. Now we are ready to extract the audio from the video files:

ffmpeg -i input_file.flv output_file.mp3

The above command will extract the audio from a Flash video file. You can do the same for a QuickTime file as well:

ffmpeg -i input_file.mov output_file.mp3

Or for an Audio Video Interface file:

ffmpeg -i input_file.avi output_file.mp3

YouTube and other video web sites:

Having done all this, now we can download flash files from places like YouTube and strip the audio from them. All you need besides the steps above is a way to save the Flash files (.flv) from YouTube. An easy way to do that is by using Firefox Add-ons like Download Flash and Video or Flash Video Downloader.

The quality of the audio in the YouTube videos for example is 64 bit/sec. Most of the mp3 files are normally compressed to 128 bit/sec or above. Obviously the quality will not be the same, but a human year cannot tell the difference.

The quality of the extracted mp3 will depend on the quality of the audio track in the video file. So the above statement about the 64 bit/sec audio is mostly the case for the files on some video sharing sites.

How to Resume Partial File Transfers

I work primarily with UNIX and Linux machines and scp is my main choice to transfer files with. It is both convenient, short and secure.

Example:

scp localfile user@remotecomputer:/path/to/target/dir

Recently I was transferring an 8GB file and due to a network issue, the transfer was interrupted at nearly 40%.

I found a solution at joen.dk ,which uses rsync to resume the transfer:

rsync --partial --progress --rsh=ssh host:remote_file local_file

Now we can improve this slightly by shortening the above command. We can substitute –rsh=ssh with -e ssh, and use -P instead of –partial –progress. Also, you can add user@host if you need to specify a different remote shell user:

rsync -P -e ssh user@host:remote_file local_file

This above example will work with any file that was partially transfered. How the transfer was started does not really matter. It could be through scp, nc or even ftp. After you execute the above command it will take rsync a little time to verify the previously downloaded part before it continues with the rest. Be patient, depending on your network speed rsync could take some time to go through what you have already transfered. Of course this is much faster than if you were to start the download all over again and it shows you the progress in percentages.

Keep in mind that there have to be a couple of requirements in place in order to resume the file transfer with rsync:

1. You should have remote shell access.
2. The remote machine should have rsync installed. Since rsync is by default on most Linux distributions that generally should not be an issue.