Ripping

From Wikipedia, the free encyclopedia

Ripping is the process of copying audio or video content to a hard disk, typically from removable media or media streams. The word is used to refer to all forms of media. Despite the name, the media is not damaged during the extraction process, nor is the data deleted from the source.

Digital audio extraction is a more formal phrase applied to the ripping of audio CDs. Ripping is distinct from simple file copying, in which, the source audio/video is not formatted for ease of use in a computer filesystem. For example, the hierarchy of files making up the audio/video data on a DVD-Video disc can be encoded into a single avi file. In addition, the copied data are often compressed with appropriate codecs. Ripping is often used to shift formats, and to edit, duplicate or backup media content. Media files released on the Internet may describe the source of the rip in their names, e.g. DVD-Rip.^[1]

Contents 1 Ripping Software 2 Legality 2.1 United States 2.2 Other 3 Obtaining an accurate rip 4 See also 5 References 6 External links

[edit] Ripping Software

A CD ripper, CD grabber or CD extractor is a piece of software designed to extract or "rip" raw digital audio (in format commonly called CDDA) from a compact disc to a file or other output. Some all-in-one ripping programs can simplify the entire process by ripping and burning the audio to disc in one step, possibly re-encoding the audio on-the-fly in the process.

[edit] Legality

[edit] United States

The legality of ripping is controversial. It allows content to be losslessly copied for a very low or essentially zero cost. The copy (or the original) could theoretically be passed to someone who did not purchase it. If someone uses copyrighted material without permission of the copyright holder (under conditions not covered by fair use), a copyright violation has occurred. What is unclear is exactly when the crime has occurred and if ripping itself was part of the criminal act. Ripping copyrighted material for personal use is clearly not a crime, however ripping it and passing it to others clearly is a crime (again, only in conditions not covered by fair use).^[2][3]

Recording industry representatives have claimed (in the context of Atlantic v. Howell) that ripping itself may be regarded as theft.^[4] However, even within the industry, this is the minority view. In oral arguments before the Supreme Court in MGM Studios, Inc. v. Grokster, Ltd., Don Verrilli, representing MGM stated: "And let me clarify something I think is unclear from the amicus briefs. The record companies, my clients, have said, for some time now, and it's been on their Website for some time now, that it's perfectly lawful to take a CD that you've purchased, upload it onto your computer, put it onto your iPod. There is a very, very significant lawful commercial use for that device, going forward."^[5]

[edit] Other

In countries such as Spain, anyone is allowed to make a private copy of a copyrighted material for oneself and the source copy does not even have to be legal. Making copies for other people, however, is forbidden if done for profit.

In the United Kingdom, making a private copy of copyrighted media without the copyright owner's consent is illegal as of April 2009: this includes ripping music from a CD to a computer or digital music player.^[6][7] The UK government has made proposals to allow people to make copies of music for personal use.^[8]. According to one survey, 55% of British consumers believed ripping a CD to be legal, and 59% admitted to doing it.^[9][10].

[edit] Obtaining an accurate rip

This section does not cite any references or sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (March 2009)

CD audio has two major design constraints that make it difficult to obtain accurate copies in the form of a standard digital file. First, the system is designed to provide audio in real time in order to ensure continuous playback without gaps. For this reason, it does not provide a reliable stream of data from the disc to the computer.

Secondly, the designers felt that it would be preferable for major scratches in the disc to be covered up rather than resulting in total failure. Normally, an error correction system such as Reed Solomon would provide either a perfect copy of the original error-free data, or no result at all. However, CD audio's Cross-interleaved Reed-Solomon coding includes an extra facility that interpolates across uncorrectable errors. This means that the data read from an audio CD may not in fact be a faithful reproduction of the original.

Another practical factor in obtaining faithful copies of the music data is that different CD drives have widely varying quality for reading audio. Some drives such as Plextor are thought to deliver extremely accurate copies while others may do little or no error correction and even misreport error correction information.

Obtaining an accurate digital extraction or "rip" under these circumstances is difficult. iTunes includes an "error correction" mode in its CD importing system. Technical information about this mode is not available from Apple, but it probably ensures that iTunes will attempt to error-correct all data it reads off the disc. However, iTunes does not report if interpolation occurred due to uncorrectable errors.

There is specialized software that will attempt to correct errors, and also attempt to report if errors could not be corrected. They use a variety of techniques, such as making use of error correction information, knowledge of the peculiarities of different drives, and ripping multiple times and comparing the results. All of these programs are still susceptible to some degree to poor CD drives.

[edit] See also

• Game rip
• CD ripper
• DVD ripper
• Radio music ripping
• Digital Rights Management
• Telecine (piracy), a pirated copy of a film created with a telecine.
• DVDScr (DVD Screener)
• R5 (bootleg)
• Riplock
• Exact Audio Copy

[edit] References

[edit] External links

• Etymology of ripping
• LAME Open source encoder