Tried to Google this and came up with a bunch of links way more complicated and irrelevant than what I’m asking. Essentially, on most late-model cars (I’m guessing ALL of them, since I drive a rock-bottom Honda Fit) when you’re listening to the radio a readout will tell you the station you’re listening to. Not only that, their tagline. Then what song you’re listening to and who sings it.
How is this possible? I mean, I can understand how this happens with a CD because it’s encoded into the DVD itself somehow. But radio playlists seem to be totally random, especially during “request” shows.
without going into details, my understanding is that its part of the broadcast signal, not all stations around the country do it (yet) just as not all autos have the electronics to display the info (yet).
and double whammied while trying to spell correctly…
Radio Broadcast Data System (RBDS) is a digital data stream that is embedded in the radio signal. Your radio is only displaying what the radio station is sending in the RBDS stream. Not all radio stations use RBDS. RBDS was developed before HD radio and can be used with analog broadcasts.
Is the data that allows performing rights organizations such as ASCAP, BMI, or SESAC to track plays for royalty calculation.
It is encoded in the digital files - with unique identifiers for various formats, regions, what have you - and can also be read by devices such as your car radio or mp3 player.
When you import songs into a media software players (such as iTunes), it totally ignores such useful information and instead tries to match the ID3 tags appended to the file (assuming mp3 format) or the CDDB data for audio CDs and wav files in general.
This is a great feature when it works, but it’s definitely hit and miss, depending on the material and when it was encoded.
In HD (hybrid digital) radio, the broadcast signal is still analog but there’s an in-band on-channel digital stream. That allows legacy radios to still receive the broadcast.
It is a newer implementation of rights management, tailored for digital formats. It really came into prominence with the rise of the CD. It identifies the specific recording of the piece of music.
There is also the ISMWC which identifies the actual work itself - not the recording specifically. it’s a little older. It’s similar to an ISBN for a book.
The industry is trying to move towards the GRId which would contain both identifiers plus other information as detailed in the wiki link.
Prior to these digital identifiers, it was more haphazard.
The ISRC code is just a number. To display “Katy Perry/Firework” your radio would need access to some kind of data base in which it could look up that ISRC code US-S1Z-09-00001 corresponded to “Katy Perry/Firework” so that it could display that for you. Clearly, your car radio does not have that. (Even if it came pre-programmed with a data base of ISRC codes, it could not display the name of a song that was released after the radio was installed in your car.) And the ISRC would not contain the name of the radio station.
Your radio is displaying the text that is contained in the RBDS stream which is generated by the radio station.
Right, but did they have this kind of information feed before HD radio? That is to say, an automated way to track play lists in order to figure out royalty payouts?