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Greater Media’s typical installation overview. Note
the Jump2Go box is the center of communications for AE and analog RDS. (Click to Enlarge)
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As HD Radio continues to improve, more and more
features are added to the data set that is broadcast. In addition to HD1, HD2,
Program Associated Data (artist, title and genre) and traffic services, a
service called Artist Experience has been added by iBiquity Digital. It allows
broadcasters to embed album art, station logos and other graphic content into
the digital bit stream in real time for the purpose of being displayed on
compatible receivers.
There are now several receiver manufacturers that sell
AE-capable units, including JVC and Insignia, with more to come this year. This
article describes some of my efforts to implement AE in Boston at Greater
Media’s cluster of five FM stations.
The road to implement AE was long, and for us started
in December of 2011, but once we learned how to do one station, the others were
fairly easy. One of our stations is fully automated. We decided to implement AE
on WBOS because this presented the most stable testing platform, with no
concern of the event queue being disturbed by DJs moving elements around.
Eventually we implemented AE on our live stations,
and finally on two of our stations that are Broadcast Traffic Consortium
stations. BTS has specific guidelines that need to be respected when running AE
concurrently; these are not difficult to implement.
Today there are two paths to take. Allen Hartle’s
company Jump2Go offers a solution, as does Emmis Interactive’s TagStation
product. They both work well; I would hesitate to recommend one over the other.
The biggest difference in my opinion is that Jump2Go relies on external
hardware, consisting of small interface boxes called jump gates, to communicate
with outside servers, while TagStation relies on and requires Broadcast
Electronics’ “The Radio Experience” software to interface to their servers.
For the time being, Greater Media in Boston is using
the Jump Gate approach, so I will concentrate on discussing that. Greater Media
was already doing business with Allen Hartle for iTunes Tagging, so
implementing AE was a natural extension using common hardware already in place.
The Artist Experience begins with the digital
play-out system, and in our case that is the BE AudioVault. Additionally I am
aware that ENCO Systems, Wide Orbit and RCS Master Control are supported for
non-delayed art, meaning the image shows up on the receiver immediately when
the event starts. As of this writing, there are some other systems that are
supported with delayed art, and they include iMediaTouch, Maestro, Dalet, Dial
Global and Jelli. These automation systems will work with AE, but cannot
pre-buffer the image, so the picture shows up a few seconds after the song
starts.
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JVC car radio displays station logo during a
commercial airing on WMJX.
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The illustration shows a typical configuration using the
Jump2Go approach.
The
automation system sends information to the interface box, which is the Jump
Gate in our case. The Jump Gate reaches out to a few different servers for
information about the music, and the actual album art image. This information
is retrieved and sent to the importer, which accepts image data for HD1 and
HD2, as well as Program-Associated Data for HD2. Pad data for HD1 is sent to
the exporter. The interface also sends radio text to the RDS encoder in real
time, and can feed a Web client for a more complete online experience.
This
description is a highly simplified explanation of what happens with the
JumpGateHD, which services analog RDS as well as HD.
There
is actually quite a bit of behind-the-scenes data transfer going on to buffer
and retrieve the images, as well as to send special lot IDs to the receiver at
the correct time to actually display the album art on the receiver in sync with
the start of the audio. This is done by way of the iBiquity Java Multiport
Synchronous/Asynchronous Client. The JMSAC acts as a transaction server and
manages the queue structure. It also is responsible for broadcasting an
identifier call Lot ID that is associated with each event to cause the receiver
to display the correct image at the correct time. The Lot ID is a marker that
is sent with each image to match up with that image; the marker allows the image
to be displayed on the receiver in sync with the audio.
The systems
from Jump2Go and Emmis Interactive both provide nice Web interfaces to allow
you to configure, monitor and troubleshoot the data flow. IBiquity also has
some specific hardware and software tools that were made available to us for
initial debugging. Obviously one of the best tools you can have is a receiver
capable of displaying the album art. In our case we used a variety of
receivers; our best unit was the JVC car radio model KW-NT3HDT.
As a side note, the radio’s firmware needed to be
updated to the latest version to allow AE images to be displayed. However this
can be easily done in the field using an SD card.
Before implementation
There are important prerequisites to implementing
AE. First of all, be prepared to upgrade your importers and exporters. The
importers must be using Ibiquity software version v4.3.1P1 or later, and the
exciters/exporters need to be running ver. 4.3.2 or later.
With regard to the importer, this upgrade requires a
clean installation. However this is made easier by the fact that the version 3
database can be restored into the new system.
Following the restoration, the bandwidth allocation is
specified, and this is where you have the opportunity to choose between mode P1
and P3 of the iBiquity system. If you choose to use the extended hybrid mode
(P3) you will have a total of 151 kilobits-per-second throughput available, as
opposed to mode P1 that is limited to 100 kbps. However the extended hybrid
mode requires about 0.8 dB more transmitter power headroom and also is not
compatible with higher order (96 kHz) analog subcarriers. Of course running in
the extended hybrid mode does allow more bandwidth for audio services, and this
can be important if you are running an HD2 or HD3 program channel.
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Typical P1 bandwidth allocation chart
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The chart shows a typical bandwidth allocation scheme for a radio
station running in MP1 mode with HD1, HD2 programs, as well as AE. As you can
see there is not a lot of extra room for other services, with in this case the
SPS1 Audio service already limited to 32 kbps. The images that are broadcast
need to conform to fairly specific specifications. They need to be 24 bit JPG
files with a maximum of 200x200 pixels. The maximum file size should be limited
to 12 kilobytes.
During commercials, it is possible to broadcast
images from sponsors, for example show the Coke logo during a Coke spot, and
sell this as a value-added service. Additionally between songs or during public
service shows, the radio station logo can be shown. There is a way to transmit
this logo to the radio asynchronously to be held in non-volatile ram for
immediate and frequent display when needed.
Custom messaging is also possible to do though the
use of the PSDGENTX, a software developer kit published by iBiquity. Using this
I have successfully broadcast images of our FM talk personalities during the
times they were on the air since there is no album art to broadcast on a talk
station. Other information such as weather and financial data can be sent as
well.
Lessons learned
Some of the biggest problems we ran into were image
lookup failures. Either the images provided were too large, or not the most
appropriate one, such as the best of the 1960s compilation as opposed to the original
artist. In some cases even profane or indecent images that were not appropriate
for broadcast were returned. These obviously needed to be weeded out and
handled on a case-by-case basis.
Also, getting the timing correct was a bit touchy.
Some of our stations run profanity delays in addition to the inherent HD Radio
transmission delay, so those delays need to be compensated for to make the
images appear on the radio in concert with the song.
HD Radio offers a whole range of new options for
broadcasters, and some of those options have not even been thought of yet. As
we strive to compete more effectively with other digital media, AE is just
another tool we have available to us to provide a more rich experience to our
listeners.
In hindsight
It took us about six
weeks to implement Artist Experience on WBOS. That’s because we were one of the
first stations to do so, and we had challenges getting Jump2Go to learn how to
communicate with our AudioVault. We were also trying to bring iBiquity, Hartle
and BE on the same page with respect to AE implementation. Coordination and
cooperation with all three proved to be time-consuming.
We eventually solved
all those problems and now there is a clear path. We benefited from this
process when implementing AE on our other stations in Boston and other Greater
Media Markets.
Comment on this or any article. Email to
radioworld@nbmedia.com with “Letter to
the Editor” in the subject field.
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