Programmer’s testimony

 

This time I would like to invite you to my project jakubiak-red5, the purpose of which is the combination of the following technologies : Red5, Xuggle and Maven2. Xuggle is a tool for the conversion of video images in real-time. Red5 is a server of multimedia applications. Maven2 is the most efficient tool for organizing the process of building applications. My goal is to combine them all together.

 

My project is ,in fact it is a building script. It is supposed to be an instruction for Maven2 on how to build server Red5 and a (Java) part of Xuggle library. Let’s have a look on how it works. In SVN repository there is a structure of the Maven project, along with the files pom.xml. The source code of Red5 and Xuggle libraries does not change because it is connected to the source code of the original projects using svn:externals. All you need to do in order to build a project is to write mvn clean install. I assume that each Java programmer is already a fan of Maven or will become such in a future, so there is no need to dwell on it any more.

The results of work are the dependencies that can be used in a new project – a new Red5 based application (or Red5 and Xuggle based).

Welcome to a battle-field!

What we need is Xuggle. The installation of Xuggle Instalacja Xuggle jest prosta seems to be suprisingly simple, compared to the capability of this library (at least for Windows) Setup.exe.

The next installation is Red5. I recommend you to try wersje 0.8RC2 version. Again, follow the procedure setup.exe. For Windows you will need a 32-bit Java.

One more thing – a binary Maven2. Download, unzip and try out.

Finally, you need to download the sources of my project:

svn checkout http://jakubiak-red5.googlecode.com/svn/trunk/ jakubiak-red5-read-only

 

This command is supposed to download the sources of my project as well as the sources of Red5 server, and partly the sources of Xuggle project. Now it’s time for a testing compilation:

cd jakubiak-red5-pom/
mvn clean install
cd ../jakubiak-xuggle-pom/
mvn clean install

 

Yet, before we can finally see this long expected message, we need to use the Internet to download a few dependencies which, for a couple of reasons, might not be found in depositories and they are not downloaded automatically.

It’s a testing time now. You need to publish on the Red5 server the examples build by my script ; in other words, just copy the directories:

cp -r jakubiak-red5-oflaDemo/target/jakubiak-red5-oflaDemo-0.8-SNAPSHOT/ ../../Program Files (x86)/Red5/webapps/
cp -r jakubiak-xuggle-xuggler-red5-videotranscoder/target/jakubiak-xuggle-xuggler-red5-videotranscoder-1.0-SNAPSHOT/ ../../Program Files (x86)/Red5/webapps/
net start Red5

 

Once we start up the internet browser, we can try out a few examples:

• http://localhost:5080/demos/ofla_demo.html
• http://localhost:5080/demos/publisher.html

If we want to see Xuggle “in action”, we need to connect to the application videotranscoder: rtmp://localhost/videotranscoder using the Publisher program. The name of the stream should be preceded by a prefix “xuggle_“.

My library Jakubiak-red5 to some extend replaces the usual building process. Red5 and Xuggle are built by means of Apache Ant and Ivy (I am genuinely thrilled hearing these names). I, on the other hand, prefer building them using Maven2. It is quite a complex and time-consuming process, yet it is definitely worth the shot, because it enables me to create applications combining lots of fascinating technologies, for example: JPA, Spring. I can also create the WAR application including Red5 and Xuggle, which will then be started up on Apache Tomcat 6. Moreover, I can enjoy working with Eclipse IDE. To sum up, it offers lots of opportunities.

However, the most significant fact is that my library does not modify the sources of Xuggle and Red5 projects.

One of the alternatives to my building script would be to add the libraries of JAR, Red5 and Xuggle straight to the Maven repository. But, this method will not be sufficient in building WAR version of Red5 application. WAR version is extremely useful, but I will return to this issue next time.

July 26, 2007

Some time ago I decided to keep track of my daily activities and schedules using Google Calendar. What I need today is an overview – to check how much time I actually spent on a particular activity. I would like to check out how much time it took me to work on my client’s project, or how many enjoyable hours were assigned to playing basketball.

Recently I have come up with a few code lines which demonstrate how to start an integration of Google Calendar and Zend Framework. Today I decided to proceed with it and get down to the project again. I started working on Google Gadget, – a tool which is supposed to perform this kind of integration. Right now the gadget is capable of downloading the tasks from an average-size calendar, calculate the total work time for all the records in a calendar, as well as for the records whose titles correspond to a given phrase. It is possible to define several phrases. All in all, it seems to be a quite promising herald of a project that a wide group of net surfers might find very useful. The project is available at: http://code.google.com/p/task-calculator/ To find the gadget you need to go here: http://task-calculator.googlecode.com/svn/trunk/TaskCalculatorGadget/WebContent/gadget.xml. Speaking from my experience, this gadget has already proved its usefulness and sufficiency. I can easily calculate the time devoted to work vice versa the blissful hours spent on entertainment. Such “searching for lost time” makes me think about getting down to work and trying to finish this project… Anyone willing to join me and pay his tribute to the internet? You are more than welcome, the project is open, the license you need is GPLv3. Its temporary name is Task Calculator but, as I have doubts about that, it seems to me that Task Report would sound better. I am not sure yet.

 

September 27, 2007

Some time ago I began working on a new project – Task Calculator. Its function is to create a report which would sum up the total work time – I need such data for invoicing my client. The work time data are recorded in Google Calendar. The Project is still only a proof of concept – the concept itself proved right, the calculator does all the counting – however, there are still a couple of issues to be improved.

In order to start the calendar you obviously need to have your account in Google. The Task Calculator works as a gadget embedded on Google Home Page. First you have to search for the private address of XML calendar in calendar settings.

Next you need to install the gadget Taks Calculator – click here. Then you copy the URL address from Google Calendar and place it the gadget settings. There is a possibility of adding the key words, which will appear in a report.

If everything works fine, you will see the following report on a monitor.

Now you can view the summary, the monthly report or the listing of all tasks. You are welcome to use the calculator!

 

This time I would like to introduce you to a new project designed by my friend Łukasz Krajewski. Its main task is the convertion of the multimedia formats, however, it can actually do much more than that

When designing a new website we often wish to provide its potential users with the possibility to upload their own videos. The video uploading (as well as image uploading) requires performance of certain tasks by the server; these tasks mainly involve the conversion of a video into the appropriate internet format, such as FLV or H264. Unfortunately, the conversion process is often complicated. First of all, it is quite time-consuming – its total approximate time depends of the size of the video, and it can take a couple of seconds or last even several hours. Secondly, the server requires the installation of a special software which is capable of decoding as many video formats as possible, and transforming them into internet formats. The installation of this kind of software is quite complicated and it often requires a dedicated server or, at least, VPS. This is the main reason why it is difficult to design applications which enable users to upload multimedia. The Multimedia Conversion project is definitely going to make it easier.

The Multimedia Conversion (MC) project is free and available for the users of GPL license. It uses the techniques of PHP, Zend Framework and FFmpeg. Multimedia Conversion is a net web service. In brief, it works as follows: the application which is supposed to convert videos needs to call a server method. Next the MC server sends the application all the information about the status of conversion. Here I suggest you to go project Wiki for details..

What is available right now is the video conversion for FLV, H264 and 3GP, and conversion of music to the MP3 format. Moreover, during the conversion to the video format a so called “miniature” is being created – that is, a frame (a single image) from the given moment in the film. It’s a piece of cake to add new formats.

The aim of a project is to isolate a complicated process of a video conversion and place it on a separate server. Such server would be then much easier to administrate. It might be a particularly useful solution for companies, where a great amount of applications are being created, and many of them need an automatic conversion of video materials. Due to the MC server its implementation will be less expensive. The multimedia applications will no longer require the installation of a quite complex software for a video conversion. The complex process of a video conversion will be carried out on a separate server – MC. The multimedia applications served by MC can then be launched on the usual, inexpensive hosting.

If you are interested in testing the project, feel welcome to contact me and you will be provided with the access to MC server for testing purposes.

I happen to know a little about the next steps to be taken in the further advancement of MC application. The prognosis is the following: the MC application is not only supposed to be a tool for the conversion of a video format, but it will also serve as an application for film-editing. Thus we will be able to create a brand new movie using the shots cut out of existing movies. I am keeping my fingers crossed! Good luck Łukasz!!!

 

 

 

A big breakthrough today – I finally managed to start a Xuggle demo on the server Red5. I am really proud of this, because this kind of technologies will have a tremendous impact on further advancement in the Internet world. I have already given the details of the functioning of the tandem Xuggle and Red5. Now it is time to present how I have activated Xuggle and Red5 on my computer with Windows Vista64bit. I began with downloading and installing the latest version of the server Red5 – 0.8RC2. Of course I also installed the Xuggle. All the Widnows versions are really easy to install – by using the command: Setup.exe and restarting a computer. What I did next was to create an web application archive, consisting of the following files:

All the useful files can be found here:

1. http://xuggle.googlecode.com/svn/trunk/repo/share/java/xuggle/xuggle-xuggler-red5/xuggle-xuggler-red5-1.17.117.jar
2. http://xuggle.googlecode.com/svn/trunk/java/xuggle-xuggler-red5/web/videotranscoder/WEB-INF/red5-web.properties
3. http://xuggle.googlecode.com/svn/trunk/java/xuggle-xuggler-red5/web/videotranscoder/WEB-INF/red5-web.xml
4. http://xuggle.googlecode.com/svn/trunk/java/xuggle-xuggler-red5/web/videotranscoder/WEB-INF/web.xml

I then saved my application in the folder webapps in the server Red5. Using the 32bit version of Java I started the server Red5. I also set the environment variables:  

$ export | grep HOME
declare -x JAVA_HOME="C:\Program Files\Java\jdk1.6.0_10"
declare -x RED5_HOME="C:\Program Files (x86)\Red5"
declare -x XUGGLE_HOME="C:\Program Files (x86)\Xuggle"

    I started red5: red5.bat. For testing I used the demo application from the server Red5 – Publisher. http://localhost:5080/demos/publisher.html. It is important to remember to connect to the videotranscoder application rather than oflaDemo. All other settings do not require any changes. I just turn on the camera and the microphone and begin a video session. The name of the stream is antek. In order to see the results of Xuggle operations I start the option “View”. The name is xuggle_antek. After severals hours of trials and errors and using Art Clarke I got it! I’ve finally seen my “second nature” – my second faceJ Thanks a lot, Art! In the next chapter I’m going to explain how to programme Xuggle using Eclipse and Maven 2. However, first I have to learn how to do it and, most importantly, EAT SOMETHING!

I finally got it ! I managed to activate an example of the class Hello Word in tandem with Xuggle and Red5.

Now, how does it work? In the internet browser I start the application which publishes the image from the digital camera of my laptop. This image is then being converted (processed?) on the server by means of Xuggle. In this way the net surfers are able to see in their browsers the target image that has been processed by a server. Welcome to the new era in the multimedia web applications!

It seems to me that this application opens a window of new, amazing opportunities. For example, we can image a video conference which allows the participants to see each other’s if they were actually sitting together at one table:). Another possibility might be the server recognizing the users face and, as a result, greeting him with his name, nickname or some other familiar phrase. Or, for example, let’s say we visit the tourist agency website. We start our laptop’s web cam and, after a while, we could see the blissful image of ourselves resting in a hammock hanging between trees on the beautiful beach far away.

There is no doubt that the image of lying in a hammock is far more tempting than sitting at the computer desk. But let’s go back to details. What is actually going on in the server area? The server – Red5 – receives the video from the user. This video is in the form of a data stream. It might contain an image, music or other data. The video stream is, of course, compressed. The server’s is now required to decompress it so that we receive the successive shots (and this is the task performed by Xuggle and FFmpeg). In fact it reminds of the old-fashioned film tape, which has still been in use for movie-making in Hollywood.

As a result of a video’s decompression we receive a sequence of pictures. What the server does next depends entirely of the imagination and goals of the web-site designers. Then the server compresses the sequence of pictures, thus creating a brand new video – a new data stream. The server can save the results of its operation, or create and access enabling an online transfer.

Obviously this method can be also used for the processing of sound. For instance, we can introduce some changes in popular communicators, such as Skype by adding the users’ favourite music to the background, or creating other sounds typical for cafe, pub or other popular meeting places.

As you can see, the server, which is supposed to perform so many tasks, may be overloaded: it is responsible for decompression and compression of the audio / video stream, as well as processing images or sounds. During the system testing , the overload of my laptop went up to 10%. However, we should keep in mind that the server is performing a new operation, something that has never been done before . Something that might actually become a key to success. Personally I am convinced that the expected results are worth its costs, and it pays off to risk an occasional overload.

In my next article I am going to explain how to start and application Xuggle Hello World on the server Red5.

Briefly speaking, Red5 is a server of the multimedia web applications. It is undoubtedly booming right now; I have just managed to start the administrator’s panel and, since it is a complicated process, I find it reasonable to describe it here in order to remember it well.

The first step is to load the latest version of Red5 0.8RC2 from the website Xuggle . Then I install it according to instructions: I unzip and set the environment variables RED5_HOME. The next thing to do is to start the Installer application : http://localhost:5080/installer/, install the administer application and restart Red5. Thereafter, following the instructions provided on forum, I register at: http://localhost:5080/admin/register.html After registration I move to restarting Red5 again. Now I can finally log in: http://localhost:5080/demos/adminPanel.html

Using the administrator’s panel I can view the list of active applications, find the active online users or check the transfer.