オーディオ CD のリッピング

関連記事

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• MEncoder
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音楽は通常、非圧縮フォーマットでオーディオ CD に保存されるため、多くの容量を必要とします（たとえば、わずか 80 分のオーディオのために 700MB）。CD リッパーは、生のデジタルオーディオ（一般的に CDDA と呼ばれるフォーマット）をコンパクトディスクからファイルやその他の出力に抽出（「リッピング」）するように設計されています。

CDからオーディオを取り出すには、通常、同じ品質でおよそ半分のサイズになる可逆圧縮（APE や FLAC など）か、低品質でおよそ10分の1のサイズになる非可逆圧縮（MP3 や OGG など）を使って、容量が少なくて済むように圧縮します。

リッピング

物理ディスクから

See Optical disc drive#Ripping for a list of available software. For example, to extract audio with the cdrtools package:

$ cdda2wav -vall cddb=-1 speed=4 -paranoia paraopts=proof -B -D /dev/sr0

Some CD rippers support burning audio to a CD and transcoding on-the-fly (e.g. cdda2mp3).

ノート: By default, cdda2wav uses freedb.freedb.org as its Compact Disc Database Protocol (cddbp, wikipedia:cddb) server to lookup CDs. Freedb.org was shutdown on May 28th 2020 and as of 13th of June 2020, this URL used for lookups no longer seems to operate (see Wikipedia:Freedb#History). An alternative cddbp service provided by gnudb.org does exist and the parameters cddbp-server and cddbp-port could be used to access that instead.

To allow cdda2wav to create CUE files, you must also specify -t all to switch cdda2wav into a mode that creates a single audio data file for the whole CD.

Alternatively, to create a bin and cue file pair from an audio CD, use cdrdao. For example:

$ cdrdao read-cd --read-raw --driver generic-mmc:0x20000 --datafile cdimage.bin cdimage.toc && toc2cue cdimage.toc cdimage.cue

The cue file generated by this method is not the same as some may expect from tools like EAC. To convert the cdrdao formatted cue files to a "standard" cue file, try yatoc2cue^AUR.

From image files

Sometimes rather than a physical disc, only an image is available. The audio tracks can still be extracted from image files.

The bchunk program can extract data and audio tracks from a .bin / .cue pair. This example will save each data track as outputXX.iso and each audio track as outputXX.wav where XX is the track number:

$ bchunk -w image.bin image.cue output

Post-processing

Tag editors

For some examples of audio tag editors see List of applications/Multimedia#Audio tag editors.

Converting to other formats

Re-encoding to another format can be done with lame, flac or FFmpeg. For example, to convert the output raw audio files from #Ripping to highest quality variable bitrate MP3:

$ lame -V0 input.wav

To convert them to FLAC instead:

$ flac input.wav

Tips and tricks

Testing the ease, or difficulty, of ripping

As a test for the degree of difficulty you would face for a specific extraction process, one might test if they can rip only the audio data of the first track:

$ cdparanoia --batch --log-debug -- -1

Which will create the cdparanoia.log log file. And, if successful, a track01.cdda.wav file. See cdparanoia(1) for other options.

Converting that to MP3 can be accomplished with:

$ ffmpeg -i track01.cdda.wav -vn -ar 44100 -ac 2 -b:a 192k output-file.mp3

A short description of that ffmpeg line is here.

See also

• RIAA allow backup of physically obtained media under these conditions.
• lame(1) manual page, for options and presets.
• Hydrogenaudio's description of recommended LAME encoder settings.