phw/ruby-discid

Ruby bindings for MusicBrainz libdiscid

Ruby bindings for MusicBrainz libdiscid

About

ruby-discid provides Ruby bindings for the MusicBrainz DiscID library libdiscid. It allows calculating DiscIDs (MusicBrainz and freedb) for Audio CDs. Additionally the library can extract the MCN/UPC/EAN and the ISRCs from disc.

ruby-discid supports all features from libdiscid 0.6, but will also work with any earlier version. If a feature is unsupported in the libdiscid version used ruby-discid will just return a default value. The version required for a feature is documented in the API documentation.

Requirements

• Ruby >= 2.0
• RubyGems >= 1.3.6
• Ruby-FFI >= 1.6.0
• libdiscid >= 0.1.0

Installation

Before installing ruby-discid make sure you have libdiscid installed. See http://musicbrainz.org/doc/libdiscid for more information on how to do this. For Windows see also the notes below.

Installing with RubyGems

Installing ruby-discid is best done using RubyGems:

gem install discid

Installing from package repository

For some Linux distributions packages are available:

• Arch Linux AUR package
• Ubuntu PPA

Install from source

You can also install from source. This requires RubyGems and Bundler installed. First make sure you have installed bundler:

gem install bundler

Then inside the ruby-discid source directory run:

bundle install
rake install

bundle install will install additional development dependencies (Rake, Yard etc.). rake install will build the discid gem and install it.

Windows installation notes

On Windows you will need discid.dll available in a place where Windows can find it, see Search Path Used by Windows to Locate a DLL. You can install the discid.dll system wide, but it is recommended to place it in the local working directory of your application.

Also the architecture (32 or 64 bit) of the DLL must match your Ruby version. As the official build of libdiscid contains only a 32 bit version of discid.dll it is recommended to use the 32 bit version of Ruby.

If you want or need to use 64 bit Ruby you will have to compile libdiscid yourself. Refer to the libdiscid install instructions for further details.

Usage

Read only the TOC

require 'discid'

# Specifying the device is optional. If omitted a platform
# specific default will be used.
device = "/dev/cdrom"
disc = DiscId.read(device)
puts disc.id

Read the TOC, MCN and ISRCs

require 'discid'

device = "/dev/cdrom"
disc = DiscId.read(device, :mcn, :isrc)

# Print information about the disc:
puts "DiscID      : #{disc.id}"
puts "FreeDB ID   : #{disc.freedb_id}"
puts "Total length: #{disc.seconds} seconds"
puts "MCN         : #{disc.mcn}"

# Print information about individual tracks:
disc.tracks do |track|
  puts "Track ##{track.number}"
  puts "  Length: %02d:%02d (%i sectors)" %
      [track.seconds / 60, track.seconds % 60, track.sectors]
  puts "  ISRC  : %s" % track.isrc
end

See the API documentation of {DiscId} or the files in the examples directory for more usage information.

Contribute

The source code for ruby-discid is available on GitHub.

Please report any issues on the issue tracker.

License

ruby-discid Copyright (c) 2007-2023 by Philipp Wolfer [email protected]

ruby-discid is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

See LICENSE for details.

ruby-discid's Issues

Throw custom exception DiscError

Currently a general Exception is thrown.

Reconsider the put API

See discussion at JonnyJD/python-discid#29

readdiscid.rb Example: Minor Error

First and last tracks are the wrong way round.

First track : #{disc.last_track_number}
Last track  : #{disc.first_track_number}

Test ticket from Code Climate

Improve documentation for Windows usage

See notes on #14

Example in "Read the TOC, MCN and ISRCs" does not work

I get this error:

/home/ossi/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/discid-1.4.0/lib/discid/disc.rb:205:in `new': tried to create Proc object without a block (ArgumentError)
        from /home/ossi/.rbenv/versions/3.0.2/lib/ruby/gems/3.0.0/gems/discid-1.4.0/lib/discid/disc.rb:205:in `tracks'
        from ./discid.rb:15:in `<main>'

Using disc.tracks.each do |track| would fix this issue.

Test ticket from Code Climate

Provide libdiscid version

discid_get_version_string is already attached in the Lib module, but should not be considered public.

Probably set this to a constant DiscId::LIBDISCID_VERSION

Test on Windows

Provide .deb package

Test on OSX

discid.rb: rounding & Installation

In discid.rb you round the result in sectors_to_seconds, which can return the wrong value when constructing a TOC string for such as XMCD (freeDB) files, see:
http://ftp.freedb.org/pub/freedb/latest/DBFORMAT

"# Disc length: N"

where the number of seconds in the CD's play length is substituted for "N".
The number of seconds should be computed by dividing the total number of
1/75th second frames in the CD by 75 and truncating any remainder. This number
may not be rounded.

As for the documentation, it may be worth adding a note for Windows users that the MusicBrainz discid.dll in the download is to be copied to the bin directory of the Ruby installation. Also, I gave no thought to having had installed the 64-bit version of Ruby and was thus left scratching my head when discid.dll couldn't be loaded, so it's probably worth mentioning that a 32-bit install is required.

Finally, thanks for both working on this and acting so promptly :-)

Test for Ruby 2.0 compatibillity