Computers & Internet How does iTunes recognise CDs?

[Scotland]

When you put a CD in the computer iTunes (or Windows Media Player, whatever) transfers the tracks onto your PC as mp3s.

If you are connected to the internet it communicates with the CD publisher and automatically detects the album artwork and names and numbers each track.

This isn't the most groundbreaking technology in the World but how does it work for CDs I've had for 15-20 years? What unique information is automatically read off a CD that was produced years before mp3s were even invented?

 

[Pie eyed]

When you put a CD in the computer iTunes (or Windows Media Player, whatever) transfers the tracks onto your PC as mp3s.

If you are connected to the internet it communicates with the CD publisher and automatically detects the album artwork and names and numbers each track.

This isn't the most groundbreaking technology in the World but how does it work for CDs I've had for 15-20 years? What unique information is automatically read off a CD that was produced years before mp3s were even invented?

Tracks on CD's are cdda format not mp3. The basic track info is stored within track data. Album art, genre etc. info is from the net thanks to nice people who upload it for your and others convenience.
An average CD contains up to 20 tracks which more or less take up the entire 650mb capacity of the disc. The cdda tracks are converted on the fly to mp3, wav or another format by the software ripping the tracks.
MP3, Wav and 99% of other formats are compressed files which are much smaller than the original cdda files allowing you to whack a load more onto a CD-ROM.
iTunes converts to m4a format which is basically a ripped off mp3 format with additional bits of info added to make them more difficult to handle outside of any Apple product or hardware.

 

[danielcan]

Every now and again, a CD may not be identified (this could be a really new release or a really old album). The 'lucky' person can then type in the details of the artist, album name and each track name. Like Pie eyed says, these are the nice people. But this should be done on the CD version and not the imported (into iTunes) version.

If connected to the internet, the information goes into a database.

The next person to insert the same CD into their computer while connected to the internet will have the details from the database.

The most used online database is Gracenote.

 

[nicky]

Every now and again, a CD may not be identified (this could be a really new release or a really old album). The 'lucky' person can then type in the details of the artist, album name and each track name. Like Pie eyed says, these are the nice people. But this should be done on the CD version and not the imported (into iTunes) version.

If connected to the internet, the information goes into a database.

The next person to insert the same CD into their computer while connected to the internet will have the details from the database.

The most used online database is Gracenote.

Yep, one of my radiohead cds isn't recognisable. I originally thought it had to be something wrong with the coding on my cd so i tried inserting my friends copy. Didn't work.

 

[HSSB]

I've always wondered why aswell.