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Ripping is the process of copying audio or video content to a hard disk, typically from removable media such as compact disc (CD) or DVD, although the word refers to all forms of media. Despite the name, neither the media nor the data is damaged after extraction. Ripping is often used to shift formats, and to edit, duplicate or back up media content. Digital Audio Extraction (DAE) is a more formal phrase applied to the ripping of audio CDs. A rip is the copied content, in its destination format, along with accompanying files (such as a cue sheet or log file from the ripping software). Ripping is distinct from simple file copying, in that the source audio or video often isn't originally formatted for ease of use in a computer file system; ripping such data usually involves reformatting it and optionally compressing it during the extraction process. The source material being ripped doesn't need to be digital; ripping can involve digitizing audio and video originally stored on analog formats, such as vinyl records. == 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. For example, audio CDs contain 16-bit, 44.1 kHz LPCM-encoded audio samples interleaved with secondary data streams and synchronization and error correction info. The ripping software tells the CD drive's firmware to read this data and parse out just the LPCM samples. The software then dumps them into a WAV or AIFF file, or feeds them to another codec to produce, for example, a FLAC or MP3 file. Depending on the capabilities of the ripping software, ripping may be done on a track-by-track basis, or all tracks at once, or over a custom range. The ripping software may also have facilities for detecting and correcting errors during or after the rip, as the process is not always reliable, especially when the CD is damaged or defective. There are also DVD rippers which operate in a similar fashion. Unlike CDs, DVDs do contain data formatted in files for use in computers. However, commercial DVDs are often encrypted (for example, using Content Scramble System/ARccOS Protection), preventing access to the files without using the ripping software's decryption ability, which may not be legal to distribute or use. DVD files are often larger than is convenient to distribute or copy to CD-R or ordinary (not dual-layer) DVD-R, so DVD ripping software usually offers the ability to re-encode the content, with some quality loss, so that it fits in smaller files. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ripping」の詳細全文を読む スポンサード リンク
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