\documentclass[oneside,titlepage]{article}

\usepackage{common}
\usepackage[ps2pdf]{hyperref}

\author{darkness}
\title{\textbf{Standards for Music Organization on Contemporary
Filesystems}}
\date{Version 0.3.1\\Last revised: September 13, 2006\\Generated: \today}

\begin{document}

\maketitle

\tableofcontents
\newpage

\section{Introduction}

This document specifies organizational standards for digital music
stored on contemporary filesystems.  The primary goal is to achieve
consistency in organization and naming of music files.

This document relies heavily on ``Standards for Music Information''
\cite{SMI}, and uses many of the same terms defined in that document.
Fields defined in \cite{SMI} may be referred to as ``SMI fields''.

\section{Conventions and assumptions}

A \emph{contemporary filesystem}, for purposes of this document, is a
filesystem that contains files organized into hierarchies of
directories.  An example of contemporary filesystems would be VFAT
(Microsoft Windows 95), NTFS (any version; Microsoft Windows NT,
2000), ext2 (Linux), HFS (MacOS), or UFS (many different ``UNIX''
operating systems).  The filesystem should retain case, though it does
not need to be case sensitive.

This document uses examples based on a typical UNIX filesystem.  This
means ``\texttt{/}'' will be used as a directory delimiter.  For
example, ``\texttt{foo/bar}'' indicates a directory named
``\texttt{foo}'', and a directory under that directory named
``\texttt{bar}''.  This separator should be replaced with the
appropriate delimiter for your particular filesystem.

Filesystem-specific nuances (for example, filename extensions to
determine media type) are explicitly permitted.  These nuances are not
covered here unless otherwise noted, and any examples are free of any
such nuances.

Each track is presumed to be stored in its own file.  This standard is
likely not applicable to other cases (for example, multiple tracks
stored in a single file).

\section{Directory structure}

There is a directory structure that is used to group like tracks
together.  This directory structure first groups by artist, then by
set and collection.  This section describes the naming of both of
these directories.

\subsection{Artist grouping}

The first level of grouping must be in a directory named after the
contents of the SMI field artist name.  For purposes of artist
grouping, the artist name field must have a consistent name for all
tracks in a set.

Compilation set, as defined in \cite{SMI}, are treated differently.
Compilation albums must use methods 2 or 3 as defined in \cite{SMI}
section 4.2.1 for the artist name value when creating the artist
grouping directory structure for a compilation set.

\subsection{Set and collection grouping}

The second level of grouping must be in the following format
(references to SMI fields):
\begin{center}
\texttt{Set title (Set subtitle) - Collection title (Collection
subtitle)}
\end{center}
Any unset fields must be omitted, including their surrounding
parentheses if any.  The separating ``\texttt{ - }'' is only allowed
and required if there are one or more set (non-empty) fields on each
side of the separator.  There should be no leading or trailing spaces,
and never two or more consecutive spaces, including in values from SMI
fields.  A sequence of two or more consecutive spaces must be replaced
by a single space.

\section{Filenames}

Each track, after being placed under its proper directory structure,
must be named in the following format:
\begin{center}
\texttt{TP. Track title (Track subtitle - Modification subtitle)}
\end{center}
Where ``\texttt{TP}'' is the SMI field track position and the other
portions are references directly to SMI field names.  If either track
subtitle or modification subtitle are unset, the separating hyphen
(``\texttt{ - }'') must be omitted.  If both track subtitle and
modification subtitle are unset, everything after the track title must
be omitted.  The track position must be given as a two-digit, zero
padded number, followed by a period and exactly one space.

\section{Character translations}

SMI field values are to be left untouched whenever possible.  The
exception to this rule is character translations, which convert
characters commonly illegal in filesystems to other character
sequences (of zero or more characters).  Characters in an SMI field
value found in the first column of
table~\ref{tab-character-translations} must be translated to those
sequences found in the second column of that table.

\begin{table}[htb]
\caption{Character translations}\label{tab-character-translations}
\medskip
\begin{minipage}{\textwidth}
\begin{center}
\begin{tabular}{|l|l|}
\hline
\textbf{Illegal character} & \textbf{Translation} \\
\hline
\texttt{/} & \texttt{,}\footnote{A comma must be followed by exactly
one space in this and all other translations.} \\
\verb|\| & \texttt{,} \\
\texttt{:} & \texttt{,} \\
\texttt{*} & Empty sequence\footnote{Effectively, ``Empty sequence''
means the illegal character must be deleted.} \\
\texttt{?} & Empty sequence \\
\texttt{"} & \texttt{'} \\
\texttt{<} (As mathematical operator) & \texttt{less than} \\
\texttt{<} (All other cases) & Empty sequence \\
\texttt{>} (As mathematical operator) & \texttt{greater than} \\
\texttt{>} (All other cases) & Empty sequence \\
\texttt{|} & Empty sequence \\
\hline
\end{tabular}
\end{center}
\end{minipage}
\end{table}

\subsection{Spaces}

Two or more consecutive spaces within a file or directory name must be
replaced with a single space.  This conversion must be performed after
character translations.

\subsection{Other illegal characters}

For filesystems which have illegal characters not listed in
table~\ref{tab-character-translations}, best judgment must be used.
In most cases, the offending character should be deleted.  However, if
removing the offending character would markedly impact the
comprehension of the directory or file name in a negative way, a
suitable replacement should be found.

\section{Coalescing tags}

When an SMI field is set but contains only tags, this field is
considered to be a \term{tag-only SMI field}.  When using an SMI field
to construct a directory or file name, and one or more tag-only SMI
fields immediately follow a set (non-empty) SMI field, the tags from
the tag-only SMI fields must be added as new tags to the first
preceeding non-tag-only SMI field.  (See \cite{SMI} for what it means
to ``add a tag.'')  After this merging, the tag-only SMI fields must
be considered unset.  This process is called \term{coalescing
tags}.\footnote{Note that this concept is stolen practically wholesale
from \cite{SID3}.}

For example, take a track where the SMI set title is
``\texttt{Exploding Sheep}'', the SMI set subtitle is
``\texttt{[GB]}'', and the SMI collection subtitle is ``\texttt{[CD
1]}''.  Without coalescing tags, the directory name for the second
level of grouping would be ``\texttt{Exploding Sheep ([GB]) - ([CD
1])}''.  After coalescing tags, the directory's name becomes
``\texttt{Exploding Sheep [GB; CD1]}''.  Note that, since the tag-only
fields are considered unset, the various punctuation that was
previously added to accomodate them (such as the parentheses and the
hyphen) is removed.

\section{Revision history}

\begin{verbatim}
Version 0.1:
- Initial version.

Version 0.2:
- Added rules for directory structure artist grouping in
  compilation albums.

Version 0.3:
- Added section on coalescing tags.

Version 0.3.1:
- Andy corrected my grammar: parenthesis->parentheses in many
  places.

$Revision: 1.4 $
\end{verbatim}

\begin{thebibliography}{MMM}
\addcontentsline{toc}{section}{References}
\bibitem[SMI]{SMI} ``Standards for Music Information.''  Vers. 0.3.
22 May 2002.  22 May 2002
\texttt{<\selfhref{http://www.codefu.org/tagging/smi/smi.pdf}>}.
\bibitem[SID3]{SID3} ``Standards for ID3 Tags.''  Vers. 0.5.  10 Apr
2002.  10 Apr 2002
\texttt{<\selfhref{http://www.codefu.org/tagging/sid3/sid3.pdf}>}.
\end{thebibliography}

\end{document}