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NAME

cdda2wav - a sampling utility that dumps CD audio data into wav sound
files
 

SYNOPSIS

DESCRIPTION

OPTIONS

-D device --device

uses device as the source for CDDA reading: For example /dev/cdrom for the cooked_ioctl interface and Bus,ID,Lun for the generic_scsi interface. The device has to correspond with the interface setting (see below). The setting of the environment variable CDDA_DEVICE is overridden by this option.

-A auxdevice --auxdevice

uses auxdevice as CDROM drive for ioctl usage.

-I interface --interface

specifies the interface for CDROM access: generic_scsi or (on Linux, and FreeBSD systems) cooked_ioctl.

-c channels --channels

uses 1 for mono, or 2 for stereo recording, or s for stereo recording with both channels swapped.

-s --stereo

sets to stereo recording.

-m --mono

sets to mono recording.

-x --max

sets maximum (CD) quality.

-b bits --bits-per-sample

sets bits per sample per channel: 8, 12 or 16.

-r rate --rate

sets rate in samples per second. Possible values are listed with the -R option.

-a divider --divider

sets rate to 44100Hz / divider. Possible values are listed with the -R option.

-R --dump-rates

shows a list of all sample rates and their dividers.

-P sectors --set-overlap

sets the initial number of overlap sectors for jitter correction.

-n sectors --sectors-per-request

reads sectors per request.

-l buffers --buffers-in-ring

uses a ring buffer with buffers total.

-t track+endtrack --track

selects the start track and optionally the end track.

-i index --index

selects the start index.

-o offset --offset

starts offset sectors behind start track (one sector equivalents 1/75 seconds).

-O audiotype --output-format

can be wav (for wav files) or aiff (for apple/sgi aiff files) or aifc (for apple/sgi aifc files) or au or sun (for sun .au PCM files) or cdr or raw (for headerless files to be used for cd writers).

-C endianess --cdrom-endianess

sets endianess of the input samples to 'little', 'big' or 'guess' to override defaults.

-E endianess --output-endianess

sets endianess of the output samples to 'little' or 'big' to override defaults.

-d duration --duration

sets recording time in seconds or frames. Frames (sectors) are indicated by a 'f' suffix (like 75f for 75 sectors). 0 sets the time for whole track.

-B --bulk

copies each track into a seperate file.

-w --wait

waits for signal, then start recording.

-F --find-extremes

finds extrem amplitudes in samples.

-G --find-mono

finds if input samples are in mono.

-T --deemphasize

undo the effect of pre-emphasis in the input samples.

-e --echo

copies audio data to sound device e.g. /dev/dsp.

-p percentage --set-pitch

changes pitch of audio data copied to sound device.

-v level --verbose-level

prints verbose information about the CD. Level is a sum of powers of two in the range 0 up to 63. Each power of two controls the type of information to be reported.

Power Description 1 show table of contents 2 show a summary of the recording parameters 4 determine and display index offsets 8 retrieve and display the media catalog number MCN 16 retrieve and display all Intern. Standard Recording Codes ISRC 32 show the table of contents in start sector notation 64 show the table of contents with track titles (when available)

-N --no-write

does not write to a file, it just reads (for debugging purposes).

-J --info-only

does not write to a file, it just gives information about the disc.

-H --no-infofile

does not write an info file and a cddb file.

-g --gui

formats the output to be better parsable by gui frontends.

-M count --md5

enables calculation of MD-5 checksum for 'count' bytes from a beginning of a track.

-S speed --speed-select

sets the cdrom device to one of the selectable speeds for reading.

-q --quiet

quiet operation, no screen output.

-V --verbose-SCSI

enable SCSI command logging to the console. This is mainly used for debugging.

-Q --silent-SCSI

suppress SCSI command error reports to the console. This is mainly used for guis.

-J --version

display version of cdda2wav on standard output.

Defaults depend on the

Makefile and environment variable settings (currently CDDA_DEVICE ).

ENVIRONMENT VARIABLES

DISCUSSION

cdda2wav stands for CDDA to WAV (where CDDA stands for compact disc digital audio and WAV is a sound sample format introduced by MS Windows). It allows copying CDDA audio data from the CDROM drive into a file on your ram-, hard-, floppy- or whatever-disk in WAV or other formats.

The latest versions try to get higher real-time scheduling priorities to ensure smooth (uninterrupted) operation. These priorities are available for super users and are higher than those of 'normal' processes. Thus delays are minimized. Please note that you need newer kernels and c libraries to take advantage of this feature.

If your CDROM (not yet for SCSI drives) is on device /dev/cdrom and it is loaded with an audio CD, you may simply invoke cdda2wav and it will create the sound file audio.wav recording the whole track beginning with track 1 in stereo at 16 bit at 44100 Hz sample rate, if your file system has enough space free. Otherwise recording time will be limited. SCSI drives have to use different devices (see files README and README.INSTALL for details).  

HINTS ON OPTIONS

Options

Most of the options are used to control the format of the WAV file. In the following text all of them are described.

Select Device

-D device selects the CDROM drive device to be used. The specifier given should correspond to the selected interface (see below). CHANGE! For the cooked_ioctl interface this is the cdrom device descriptor as before. The SCSI devices used with the generic SCSI interface however are now addressed with their SCSI-Bus, SCSI-Id, and SCSI-Lun instead of the generic SCSI device descriptor!!! One example for a SCSI CDROM drive on bus 0 with SCSI ID 3 and lun 0 is -D0,3,0.

Select Auxiliary device

-A auxdevice is necessary for CD-Extra handling. For Non-SCSI-CDROM drives this is the same device as given by -D (see above). For SCSI-CDROM drives it is the CDROM drive (SCSI) device (i.e. /dev/sr0 ) corresponding to the SCSI device (i.e. 0,3,0 ). It has to match the device used for sampling.

Select Interface

-I interface selects the CDROM drive interface. For SCSI drives use generic_scsi (cooked_ioctl may not yet be available for all devices): generic_scsi and cooked_ioctl. The first uses the generic SCSI interface, the latter uses the ioctl of the CDROM driver. The latter variant works only when the kernel driver supports CDDA reading. This entry has to match the selected CDROM device (see above).

Enable echo to soundcard

-e copies audio data to the sound card while recording, so you hear it nearly simultaneously. The soundcard gets the same data that is recorded. This is time critical, so it works best with the -q option. To use cdda2wav as a pseudo CD player without recording in a file you could use cdda2wav -q -e -t2 -d0 -N to play the whole second track. This feature reduces the recording speed to at most onefold speed. You cannot make better recordings than your sound card can play (since the same data is used).

Change pitch of echoed audio

-p percentage changes the pitch of all audio echoed to a sound card. Only the copy to the soundcard is affected, the recorded audio samples in a file remain the same. Normal pitch, which is the default, is given by 100%. Lower percentages correspond to lower pitches, i.e. -p 50 transposes the audio output one octave lower. See also the script pitchplay as an example. This option was contributed by Raul Sobon.

Select mono or stereo recording

-m or -c 1 selects mono recording (both stereo channels are mixed), -s or -c 2 or -c s selects stereo recording (doubles file size). Parameter s will swap both sound channels.

Select maximum quality

-x will set stereo, 16 bits per sample at 44.1 KHz (full CD quality). Note that other format options given later can change this setting.

Select sample quality

-b 8 specifies 8 bit (1 Byte) for each sample in each channel; -b 12 specifies 12 bit (2 Byte) for each sample in each channel; -b 16 specifies 16 bit (2 Byte) for each sample in each channel (Ensure that your sample player or sound card is capable of playing 12-bit or 16-bit samples). Selecting 12 or 16 bits doubles file size. 12-bit samples are aligned to 16-bit samples, so they waste some disk space.

Select sample rate

-r samplerate selects a sample rate. samplerate can be in a range between 44100 and 900. Option -R lists all available rates.

Select sample rate divider

-a divider selects a sample rate divider. divider can be minimally 1 and maximally 50.5 and everything between in steps of 0.5. Option -R lists all available rates.

To make the sound smoother at lower sampling rates, cdda2wav sums over n samples (where n is the specific dividend). So for 22050 Hertz output we have to sum over 2 samples, for 900 Hertz we have to sum over 49 samples. This cancels higher frequencies. Standard sector size of an audio CD (ignoring additional information) is 2352 Bytes. In order to finish summing for an output sample at sector boundaries the rates above have to be choosen. Arbitrary sampling rates in high quality would require some interpolation scheme, which needs much more sophisticated programming.

List a table of all sampling rates

-R shows a list of all sample rates and their dividers. Dividers can range from 1 to 50.5 in steps of 0.5.

Select start track and optionally end track

-t n+m selects n as the start track and optionally m as the last track of a range to be recorded. These tracks must be from the table of contents. This sets the track where recording begins. Recording can advance through the following tracks as well (limited by the optional end track or otherwise depending on recording time). Whether one file or different files are then created depends on the -B option (see below).

Select start index

-i n selects the index to start recording with. Indices other than 1 will invoke the index scanner, which will take some time to find the correct start position. An offset may be given additionally (see below).

Set recording time

-d n sets recording time to n seconds or set recording time for whole track if n is zero. In order to specify the duration in frames (sectors) also, the argument can have an appended 'f'. Then the numerical argument is to be taken as frames (sectors) rather than seconds. Please note that if track ranges are being used they define the recording time as well thus overriding any -d option specified times.

Recording time is defined as the time the generated sample will play (at the defined sample rate). Since it's related to the amount of generated samples, it's not the time of the sampling process itself (which can be less or more). It's neither strictly coupled with the time information on the audio CD (shown by your hifi CD player). Differences can occur by the usage of the -o option (see below). Notice that recording time will be shortened, unless enough disk space exists. Recording can be aborted at anytime by pressing the break character (signal SIGQUIT).

Record a complete audio CD in one go in different files

-B copies each track into a seperate file. A base name can be given. File names have an appended track number and an extension corresponding to the audio format. To record all audio tracks of a CD, use a sufficient high duration (i.e. -d99999).

Set start sector offset

-o sectors increments start sector of the track by sectors. By this option you are able to skip a certain amount at the beginning of a track so you can pick exactly the part you want. Each sector runs for 1/75 seconds, so you have very fine control. If your offset is so high that it would not fit into the current track, a warning message is issued and the offset is ignored. Recording time is not reduced. (To skip introductory quiet passages automagically, use the -w option see below.)

Wait for signal option

-w Turning on this option will suppress all silent output at startup, reducing possibly file size. cdda2wav will watch for any signal in the output signal and switches on writing to file.

Find extrem samples

-F Turning on this option will display the most negative and the most positive sample value found during recording for both channels. This can be useful for readjusting the volume. The values shown are not reset at track boundaries, they cover the complete sampling process. They are taken from the original samples and have the same format (i.e. they are independent of the selected output format).

Find if input samples are in mono

-G If this option is given, input samples for both channels will be compared. At the end of the program the result is printed. Differences in the channels indicate stereo, otherwise when both channels are equal it will indicate mono.

Undo the pre-emphasis in the input samples

-T Some older audio CDs are recorded with a modified frequency response called pre-emphasis. This is found mostly in classical recordings. The correction can be seen in the flags of the Table Of Contents often. But there are recordings, that show this setting only in the subchannels. If this option is given, the index scanner will be started, which reads the q-subchannel of each track. If pre-emphasis is indicated in the q-subchannel of a track, but not in the TOC, pre-emphasis will be assumed to be present, and subsequently a reverse filtering is done for this track before the samples are written into the audio file.

Set audio format

-O audiotype can be wav (for wav files) or au or sun (for sun PCM files) or cdr or raw (for headerless files to be used for cd writers). All file samples are coded in linear pulse code modulation (as done in the audio compact disc format). This holds for all audio formats. Wav files are compatible to Wind*ws sound files, they have lsb,msb byte order as being used on the audio cd. The default filename extension is '.wav'. Sun type files are not like the older common logarithmically coded .au files, but instead as mentioned above linear PCM is used. The byte order is msb,lsb to be compatible. The default filename extension is '.au'. The AIFF and the newer variant AIFC from the Apple/SGI world store their samples in bigendian format (msb,lsb). In AIFC no compression is used. Finally the easiest 'format', the cdr aka raw format. It is done per default in msb,lsb byte order to satisfy the order wanted by most cd writers. Since there is no header information in this format, the sample parameters can only be identified by playing the samples on a soundcard or similiar. The default filename extension is '.cdr' or '.raw'.

Select cdrom drive reading speed

-S speed allows to switch the cdrom drive to a certain level of speed in order to reduce read errors. The argument is transfered verbatim to the drive. Details depend very much on the cdrom drives. An argument of 0 for example is often the default speed of the drive, a value of 1 often selects single speed.

Enable MD5 checksums

-M count enables calculation of MD-5 checksum for 'count' bytes from the beginning of a track. This was introduced for quick comparisons of tracks.

Do linear or overlapping reading of sectors

-P sectors sets the given number of sectors for initial overlap sampling for jitter correction. Two cases are to be distinguished. For nonzero values, some sectors are read twice to enable cdda2wav's jitter correction. If an argument of zero is given, no overlap sampling will be used. For nonzero overlap sectors cdda2wav dynamically adjusts the setting during sampling (like cdparanoia does). If no match can be found, cdda2wav retries the read with an increased overlap. If the amount of jitter is lower than the current overlapped samples, cdda2wav reduces the overlap setting, resulting in a higher reading speed. The argument given has to be lower than the total number of sectors per request (see option -n below). Cdda2wav will check this setting and issues a error message otherwise. The case of zero sectors is nice on low load situations or errorfree (perfect) cdrom drives and perfect (not scratched) audio cds.

Set the transfer size

-n sectors will set the transfer size to the specified sectors per request.

Set number of ring buffer elements

-l buffers will allocate the specified number of ring buffer elements.

Set endianess of input samples

-C endianess will override the default settings of the input format. Endianess can be set explicitly to "little" or "big" or to the automatic endianess detection based on voting with "guess".

Set endianess of output samples

-E endianess (endianess can be "little" or "big") will override the default settings of the output format.

Verbose option

-v level prints more information. A binary mask allows selection of different information.

0 keeps quiet

1 displays the table of contents

2 displays a summary of recording parameters

4 invokes the index scanner and displays start positions of indices

8 retrieves and displays a media catalog number

16 retrieves and displays international standard recording codes

32 displays track start positions in absolute sector notation

To combine several requests just add the numbers and give the sum as argument.

The table of contents

The display will show the table of contents with number of tracks and total time (displayed in mm:ss.hh format, mm=minutes, ss=seconds, hh=rounded 1/100 seconds). The following list displays track number and track time for each entry. The summary gives a line per track describing the type of the track.

track preemphasis copypermitted tracktype chans

The track column holds the track number. preemphasis shows if that track has been given a non linear frequency response. NOTE: You can undo this effect with the -T option. copy-permitted indicates if this track is allowed to copy. tracktype can be data or audio. On multimedia CDs (except hidden track CDs) both of them should be present. channels is defined for audio tracks only. There can be two or four channels.

No file output

-N this debugging option switches off writing to a file.

No infofile generation

-H this option switches off creation of an info file and a cddb file.

Generation of simple output for gui frontends

-g this option switches on simple line formatting, which is needed to support gui frontends (like xcd-roast).

Verbose SCSI logging

-V this option switches on logging of SCSI commands. This will produce a lot of output (when SCSI devices are being used), which is needed for debugging purposes. The format is the same as being used with the cdrecord package from JЖrg Schilling. I will not describe it here.

Quiet option

-q suppresses all screen output except error messages. That reduces cpu time resources.

Just show information option

-J does not write a file, it only prints information about the disc (depending on the -v option). This is just for information purposes.

HINTS ON USAGE

If your hardware is fast enough to run cdda2wav uninterrupted and your CD drive is one of the 'perfect' ones, you will gain speed when switching all overlap sampling off with the -P 0 option. Further fine tuning can be done with the -n sectors option. You can specify how much sectors should be requested in one go.

Cdda2wav supports pipes now. Use a filename of - to let cdda2wav output its samples to standard output.

Conversion to other sound formats can be done using the sox program package (although the use of sox -x to change the byte order of samples should be no more necessary; see option -E to change the output byteorder).

If you really want to sample more than one track into different files in one run, this is currently possible with the -B option. When recording time exceeds the track limit a new file will be opened for the next track.  

FILES

Audio files:

There are audio files containing samples with default extensions These files are not generated when option (-N) is given. Multiple files may be written when the bulk copy option (-B) is used. Individual file names can be given as arguments. If the number of file names given is sufficient to cover all included audio tracks, the file names will be used verbatim. Otherwise, if there are less file names than files needed to write the included tracks, the part of the file name before the extension is extended with '_dd' where dd represents the current track number.

Cddb and Cdindex files:

If cdda2wav detects cd-extra or cd-text (album/track) title information, then .cddb and .cdindex files are generated unless suppressed by the option -H. They contain suitable formatted entries for submission to audio cd track title databases in the internet. The CDINDEX and CDDB(tm) systems are currently supported. For more information please visit www.cdindex.org and www.cddb.com.

Inf files:

The inf files are describing the sample files and the part from the audio cd, it was taken from. They are a means to transfer information to a cd burning program like cdrecord. For example, if the original audio cd had pre-emphasis enabled, and cdda2wav -T did remove the pre-emphase, then the inf file has pre-emphasis not set (since the audio file does not have it anymore), while the .cddb and the .cdindex have pre-emphase set as the original does.  

WARNING

BUGS

The index scanner may give timeouts.

The resampling (rate conversion code) uses polynomial interpolation, which is not optimal.

Cdda2wav should use threads.

Cdda2wav currently cannot sample hidden audio tracks (track 1 index 0).  

ACKNOWLEDGEMENTS

AUTHOR

DATE

Index

NAME

SYNOPSIS

DESCRIPTION

OPTIONS

ENVIRONMENT VARIABLES

DISCUSSION

HINTS ON OPTIONS

HINTS ON USAGE

FILES

WARNING

BUGS

ACKNOWLEDGEMENTS

AUTHOR

DATE

Партнёры:

Хостинг: