rip -- Extract Wave Files from Audio CDs
The rip module allows you to extract audio tracks from an IDE CD-ROM drive to save to your hard drive in Wave file format. It is based on [1]DAGRAB, a package written by Marcello Urbani.
Currently rip is only expected to run on Linux/Unix. It has been tested on FreeBSD and Debian Linux.
The module defines the following items:
track_info([device])
device is the path to a Unix file-like device containing the
CD-ROM. The default is /dev/cdrom.
Returns a 2-tuple containing information about the tracks on
the CD-ROM, of the form ( numtracks, [audio_track1,
audio_track2, ... audio_trackX] ) . The second variable in the
tuple is a list of integers with each integer representing the
track number of a valid audio track.
rip(track[, device[, path [, mode[, options[, callback[, call_every
]]]]]])
Rip track number track from device.
As with track_info, device defaults to /dev/cdrom.
path is the path to the resulting wave file. It defaults to
./track<track_num>.wav.
The file at path will be chmod to mode, which defaults to 0644
unless specified otherwise.
See the section below for options.
callback is a python function that will be called each time
call_every percent (default 5) of the track has been read and
extracted. rip expects that callback will return non-zero if it
should continue to extract the current track, and zero if it
should terminate.
Making use of callback is recommended, even if only to return
1. rip will not process KeyboardInterrupt exceptions while in
C, so taking advantage of this function call is an easy way to
allow keyboard TERM signals to affect program execution.
options is a dictionary that specifies a number of performance options that are analogous to their DAGRAB counterparts. Consequently, the descriptions below are lifted right from the program man page.
The key constants, which can be found in rip are:
O_OVERLAP -- overlap sets the number of sectors which are used for jitter correction. Shouldn't be too high or you will get "jumps" in your dump. The default value is 3.
O_SECTORS -- number of sectors to be read per request from the cdrom driver.
O_KEY_LENGTH -- key length is the number of keys which must be equal for a match in jitter correction. Default value is 12.
O_RETRIES -- sets the number of times to reread sectors before a jitter error is given. Default is 40 times.
O_OFFSET -- sets the maximum offset to search for jitter correction. Default is 12.
As per the original DAGRAB code, rip will adjust these variables if unusual or impractical extremes are provided by the programmer.
- Example
import rip
def go_on():
return 1
# rip track 3 from /dev/acd1c, to fileout3.wav, # -rw-rw-r--, call go_on each 5 percent rip.rip(3,"/dev/acd1c","fileout3.wav",0664,callback=go_on)
# rip track 7 from /dev/cdrom1, with some options rip.rip(7,"/dev/cdrom1",options={
rip.O_RETRIES : 42,
rip.O_KEY_LENGTH : 9,
rip.O_OVERLAP : 4,
})
# rip all of /dev/cdrom
trackinfo = rip.track_info()
for track in trackinfo[1]:
rip.rip(track)
References