CD Ripper Settings

From MythTV Official Wiki
Revision as of 23:21, 24 December 2007 by Mikec (talk | contribs) (Paranoia level)

Jump to: navigation, search

This page is reserved to describe the CD Ripper settings in MythMusic--Mikec 22:53, 18 December 2007 (UTC) Feel free to add if you beat me to it

Some words in CD Paranoia, bit rates, file sizes, formats etc

Ripping CD Music

Extracting the digital music information from a CD and putting it onto your Hardrive is referred to as Ripping. MythTV uses an Open source library called CD paranoia to achieve this. There is a misnomer that this is a relatively error free process, as the music is held as a digital stream of numbers, and it should therefore be a simple matter of copying this information stream to the hard drive.

The real problem is a CD Audio is not a random access format like a data file. It was desinged to be read from front to back in one continuous sequence. if you drop a bit in the transfer, it can take the system many bits after before it re-synchronizes the data stream. This can result in audio clicks. If you then throw in a modern pre-emptive multitasking operating system into the mix, the chances of getting that data off the CD in one piece is not as easy as it seems. Of course if you are then going to compress that music stream to a nasty lossy compressed format such as MP3 or .ogg then you probably don't really care, because you are going to throw most of the music information away. If you are an Audiophile then you will want to treat that CD data stream with velvet gloves, and CD Paranoia is a good start. If you are using windows then you might look at DAE.

Paranoia level

The paranoia level tells MythTV how much care it should take in extracting the audio information. The general principle of less hast less waste applies. The faster the extraction the more chance of dropping bits and having holes in your audio stream.

MuiscRip.png

Audio compression

Once CD paranoia has extracted the Music data it will typicall write this out as a WAV, AIFC, AIFC or raw 16 bit linear PCM data stream. MythTV then compress this raw music stream into a compressed format that reduces the amount of space that music stream takes on your hard drive.