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Installing a Quantel ISA Manager with DummyServers for test development

May 18th, 2012

Ever since Quantel created a Windows Installer for it’s ISA Manager it has become really easy to install and upgrade it. This article will take you through installing and setting up the ISA Manager with 3 Dummy Servers to play with. The Dummy Servers have the same CORBA interface as the Quantel sQ servers and behave like them too. You can record rushes, create clips, clone between servers and do all the normal stuff; the only difference is that there’s no real pictures.

The latest ISA Manager is available on the Quantel web site or through your account manager. The installer only works on Windows.

  1. Right-click on the ISAManager-setup-Vx.x.x.x executable and select Run as administrator.
  2. Click Next to get passed the welcome screen.
  3. Click I agree to accept the user agreement.
  4. On the Database Configuration->Passwords screen accept the default passwords. This defaults to root for the user name and the host name in lower case for the password. Then click Next to move on.
  5. From the Select the type of install drop down select Install Master. You will see all the components which will be installed. You can not alter this selection. Click Next.
  6. Accept the defaults for the Start Menu shortcuts’ location, then click Next.
  7. On the Database configuration->Language screen choose the language collation you would like for the database. Collation determines text sort ordering which ties in with using different character sets. Leave it on utf_general_ci if you are not sure.
  8. Uncheck the I am at Quantel checkbox. This feature can only be used in combination with the ISA Manager source code and a host of debugging tools. For you it will just slow things down, so click Next to continue.
  9. On the Database configuration->Configuration screen choose Plug-n-play Dummy Server Configuration. This will install sample data for dummy servers within a dummy zone. Click Next after you make your selection.
  10. Accept the default of 2096 for the IOR port. This is the HTTP port that is used to deliver the IOR string. This value is largely obsolete because the ISA Manager runs a cut down web server which also delivers the IOR string over the standard port 80. Just accept the default and click Next.
  11. Depending on your region your system will need to be PAL/625 or NTSC/525, so make your selection on this screen and click Next.
  12. This is a new installation and not a Legacy system so just accept the defaults for this screen and click Next.
  13. We don’t want to be a Sequence master either. You would only use this if you are installing front end editors as well, which you are not.
  14. Finally click Install.

The next article will be an instructional guide to running the ISA Manager and Dummy Servers. We will look at how to use the ISA controller to record a clip, create a sub clip, search for them, then play them out through a Dummy Server and finally deleting them.

Compiling the Quantel’s quentin.idl

May 11th, 2012

In order to drive the Quantel Broadcast system you need to compile the CORBA Interface Definition Language (IDL) file into a language of your choice. There are many CORBA IDL compilers out there: JacORB (Java), OmniORB (Python), TOA (C++), IIOP.NET (.NET) and there’s a more complete list on the Object Management Group’s web site.

Quantel’s IDL is known as Quentin.idl and may be obtained from your account manager, or the 24 hour support desk if you can’t wait! It contains the API interface’s for talking to:

  • ZonePortal - main driver module, metadata, searching, space allocation, copying media, organising running orders, registering listeners.
  • ThumbnailListener - generate thumbnails from video media.
  • StateChangeListener - receive callback notifications on status changes.
  • Server - control of playout and ingest storage servers.
  • Port - object representing a video port.
  • PortListener - callbacks relating to Port status changes.

This article just covers compiling the IDL into your language of choice: coding fun comes later! Due to the amount of IDL implementations there are this will have to be a cut down guide limited to the languages I deal with. I’ll start with JacORB for Java. I might do Python if there’s time.

Ok, so let’s get started. I’m assuming you’ve obtained a copy of Quentin.idl and you have the Java JDK installed. Next we need a copy of JacORB.

  1. Go to the JacORB web site’s download page.
  2. At the time of writing this article the latest version was 3.0rc1.
  3. We are not interested in compiling JacORB from source so download the Binary version.
  4. Use 7-zip to uncompress it, so now we have a folder called d:\blog\jacorb-3.0rc1.
  5. Place the Quentin.idl in the top level folder d:\blog.
  6. There isn’t an installer as such because the package assumes that you have downloaded the source code and are compiling from scratch. So to avoid downloading and installing all sorts of supplementary requirements we are just going to frig the file we need to make it work.
  7. Edit D:\blog\jacorb-3.0rc1\bin\idl.bat and change the classpath:

    -classpath “D:/blog/jacorb-3.0rc1/lib/idl.jar;%CLASSPATH%”

  8. Almost there! Now we need to open a command window and go to the d:\blog folder where the Quentin.idl file lives.
  9. Type:

    jacorb-3.0rc1\bin\idl.bat -all -genEnhanced -d src -i2jpackage Quentin:com.quantel.quentin Quentin.idl

  10. This will compile the IDL into the target language, creating a folder called src in the current directory which contains all the com.quantel.quentin package source code.
  11. Now we have the source, we can compile.
  12. The Java compiler, is frankly a pain in a arse, so if anyone knows a better way of doing this then please leave a comment.

    dir /s/b src\**.java > src.txt
    mkdir bin
    javac -d bin -cp “jacorb-3.0rc1\lib\jacorb.jar” -sourcepath src -g @src.txt

  13. Finally we need to package all that compiled code into a Java Archive (Jar) for easier access.

    jar -cf quentin.jar -C bin .

  14. This will produce a file called quentin.jar in your current folder (d:\blog).

That’s it! We will use the quentin.jar in combination with the jacorb.jar to create our application to drive the Quantel Broadcast system.

Next lesson - obtaining the IOR and connecting to the ZonePortal.

Mastering the Quantel IDL

May 9th, 2012

Quantel is a technology company based in Newbury (England) that describes itself as:

Quantel develops innovative, world-leading content creation systems for broadcast, post and DI. We are driven by a passion to create the most powerful and efficient tools for the digital age. Quantel technology means business; our systems combine industry-leading performance with total scalability to enable productive workflows for post production, graphics, digital intermediate and news/sports production.

The main product for the Broadcasting division is the Broadcasting Server system which consists of sQ Editors (glossy front end editing station), ISA Managers (the brains) and sQ Servers (storage).

One of Quantel’s unique selling points is that the storage system is highly efficient; no 2 frames are stored twice in their patented technology called FrameMagic. A huge advantage of this is when you are versioning, that is producing a version of the film for the UK market and then another version for the Japanese market. All the pictures for both versions of the film are only held once. The bits of film that are unique are held separately and are seamlessly stitched together to produce 2 versions. So the same film versioned for 10 countries’ laws will only occupy the same storage space of one and a little bit’s worth of storage space. This is unlike most of the competitor systems where it will occupy 10 times the space. The advantages don’t stop there! If you want to copy the 10 versions from the edit server to the playout or archive server then The Quantel System manages the copy ensuring that no to frames are copied twice, so copying the 10 versions will be 10 times quicker than an equivalent file based storage system. Cool!

One can use the Quantel Server system to record video, copy it between servers, create new clips from recorded rushes, search for media, add tagging information to rushes (which follow the media around, in and out of edits) and all sorts of other video and audio related functions. Quantel exposes it’s Application Programmer Interface (API) so that anyone can control the Quantel server system. This interface is used by lots of automaters to schedule records, making back ups, housekeeping, etc. The API is written using CORBA which is basically a convenient way of passing objects around a network, it’s similar to RMI (Java only) or COM (Windows only).

This article will join together a series of articles on how to get the most from the Quantel IDL to control the worlds most powerful video editing system.

If you can’t wait and you want to get started straight away then I’m available for consultancy, just drop me a line. No application too small, no language too difficult*.

Set up and using a test system

Development

Note: Now that I’m freelancing full time the articles won’t be “coming soon". I don’t want to give away all my secrets!

* provided there is an IDL compiler available for that language.

Politics doesn't really effect us does it?

May 8th, 2012

Full transcript of the a television advertisement on the BBC for their coverage of politics, with the tag line: Everything is Politics. Making politics make sense..

Politics doesn’t really effect us does it? Oh, apart from the cost of our heating; and the fat content of our food; how often our streets are cleaned; the minimum wage, the maximum wage; cycle lanes, care homes, first homes, Sherlock Holmes, oh and the air we breathe. Yeh, apart from all that!

Hibernate exception - attempted to assign id from null one-to-one property

April 26th, 2012

I wrote this 3 years ago and never really got around to finishing it properly. I’m not doing this kind of work at the moment so there’s no incentive to complete it. I’m posting it now so that it might help others and to fulfil my 4 articles a month target!

This was a tricky one to solve! Tricky because the exception doesn’t happen at the point of error - it happens down the line at the time you try to commit a transaction. This is one of those error messages you just need to know. Here is the top of the exception’s stack trace. Almost all of the rest of the stack trace is inside hibernate and doesn’t give you any kind of clue as to the cause.

org.springframework.orm.hibernate3.HibernateSystemException:
attempted to assign id from null one-to-one property: clip; nested exception is org.hibernate.id.IdentifierGenerationException:
attempted to assign id from null one-to-one property: clip

The error message we are concerned with is:

attempted to assign id from null one-to-one property: clip

Where clip is the name of property. The exception is caused by trying to save a cascading object, without persisting the entity your object is referring to.

In my case I have the classes: Clip and Aaf. A Clip has one Aaf, so I need a one-to-one relationship. My Aaf object contains a blob but unfortunately hibernate doesn’t let you do lazy initialisations on one-to-one relationships, so I’ve had to use a Set even though there is only ever one entry.

The situation is made slightly more complicated by the fact that I’m using a UUID as my primary key. Hibernate doesn’t currently support UUID so I need a custom type along with a custom key generator.

XML

<class name="uk.co.bigsoft.bus.Aaf" table="aafs">
  <id name="id" type="uuid">
    <generator class="foreign">
      <param name="property">clip</param>
    </generator>
  </id>
  :
</class>

The Aaf’s hibernate ("hbm") file above says to use a uuid identifier that is generated from the primary key of the clip property. So if we look at the Aaf class you can see that the clip property has type Clip

Code

public class Aaf
  {
 
  private UUID id ;
  private Clip clip ;
  :

As you can see above id is the record identifier but clip (mentioned in the exception) is the relationship object that is used to set the record identifier. That is id is never explicitly set by us, we set the clip property.

The first example is *wrong*.

Code

Aaf aaf = new Aaf (aafInputStream);
aafs = new HashSet<aaf> ();
aafs.add (aaf);
clip.setAaf (aafs);

I was expecting that saving the Clip would do a cascade save on the Aaf object, but is doesn’t. We need the an intermediate step of persisting the Aaf object first. In order to do this we need to fill in all the details of the Aaf record.

Code

Aaf aaf = new Aaf (aafInputStream) ;
aaf.setClip (clip) ;
aafManager.set (aaf) ;
 
aafs = new HashSet<aaf> () ;
aafs.add (aaf) ;
clip.setAaf (aafs) ;
 
sc = new AafUpdateStatechange () ;
sc.setClipId (isaClip.getId ()) ;
remoteEventQueue.send (sc) ;

XML

<class name="uk.co.bigsoft.dino.bus.Aaf" table="aafs">
 
  <id name="id" type="dinouuid">
    <generator class="foreign">
      <param name="property">clip</param>
    </generator>
  </id>
 
  <many-to-one
    name="clip"
    column="id"
    insert="false"
    update="false"
    unique-key="true"
    class="uk.co.bigsoft.dino.bus.Clip"/>
 
  <property name="content" column="content" type="uk.co.bigsoft.dino.db.types.BlobUserType"/>
        
</class>

We need to persist Aaf object, before saving the clip relationship.