The audio file selector
=======================
-Paraslash comes with a sophisticated audio file selector called afs.
+Paraslash comes with a sophisticated audio file selector called *afs*.
In the
<<
<a href="INSTALL.html">installation notes</a>,
para_client setatt test+ /path/to/the/audio/file
-Similarly, the "test" bit can be removed from a audio file with
+Similarly, the "test" bit can be removed from an audio file with
para_client setatt test- /path/to/the/audio/file
-Instead of a path you can also use a pattern, and the attribute is
-applied to all audio files matching that pattern:
+Instead of a path you may use a shell wildcard pattern. The attribute
+is applied to all audio files matching that pattern:
para_client setatt test+ '/test/directory/*'
alias para='para_client --'
-and be happy. In the remainder part this alias is being used.
+and be happy. In what follows we shall use this alias.
-Drop the test attribute entirely from the database with
+The "test" attribute can be dropped from the database with
para rmatt test
[skip this part if you don't like formal definitions]
-A mood consists of a unique name and its *mood definition*, which is a set of
-*mood lines* containing expressions in terms of attributes and other data
-contained in the database.
+A mood consists of a unique name and its *mood definition*, which is
+a set of *mood lines* containing expressions in terms of attributes
+and other data contained in the database.
A mood defines a subset of audio files called the *admissible audio files*
-for that mood. A mood can be *active* which means that para_server
-is going to select only files from that subset of admissible files.
+for that mood. At any time, at most one mood can be *active* which
+means that para_server is going to select only files from that subset
+of admissible files.
So in order to create a mood definition one has to write a set of
mood lines. Mood lines come in three flavours: Accept lines, deny
order in which admissible files are going to be selected, but is of
minor importance for this introduction.
-So we concentrate on the first two forms, that is accept and deny
+So we concentrate on the first two forms, i.e. accept and deny
lines. As usual, everything in square brackets is optional, i.e.
accept/deny lines take the following form when ignoring scores:
The set of admissible files for the whole mood is now defined as those
files which match at least one accept mood line, but no deny mood line.
-More formally, a file is admissible if and only if
+More formally, an audio file F is admissible if and only if
(F ~ AL1 or F ~ AL2...) and not (F ~ DL1 or F ~ DN2 ...)
-where F is the file, AL1, AL2... are the accept lines, DL1, DL2... are
-the deny lines and "~" means "matches".
+where AL1, AL2... are the accept lines, DL1, DL2... are the deny
+lines and "~" means "matches".
The cases where no mood lines of accept/deny type are defined need
special treatment:
Takes no arguments and matches an audio file if and only if no
attributes are set.
- played_rarely
-
-Takes no arguments and matches all audio files where the number of
-times this audio file was selected is below the average.
-
- is_set attribute_name
+ is_set <attribute_name>
Takes the name of an attribute and matches iff that attribute is set.
- path_matches pattern
+ path_matches <pattern>
Takes a filename pattern and matches iff the path of the audio file
matches the pattern.
+ artist_matches <pattern>
+ album_matches <pattern>
+ title_matches <pattern>
+ comment_matches <pattern>
+
+Takes an extended regular expression and matches iff the text of the
+corresponding tag of the audio file matches the pattern. If the tag
+is not set, the empty string is matched against the pattern.
+
+ year ~ <num>
+ bitrate ~ <num>
+ frequency ~ <num>
+ channels ~ <num>
+
+Takes a comparator ~ of the set {<, =, <=, >, >=, !=} and a number
+<num>. Matches an audio file iff the condition <val> ~ <num> is
+satisfied where val is the corresponding value of the audio file
+(bitrate in kbit/s, frequency in Hz, channel count, value of the
+year tag).
+
+The year tag is special as its value is undefined if the audio file
+has no year tag or the content of the year tag is not a number. Such
+audio files never match. Another difference is the special treatment
+if the year tag is a two-digit number. In this case either 1900 or
+2000 are added to the tag value, depending on whether the number is
+greater than 2000 plus the current year.
+
----------
Mood usage
A mood can be activated by executing
- para chmood my_mood
+ para select m/my_mood
Once active, the list of admissible files is shown by the ls command
if the "-a" switch is given:
Troubles?
---------
-Use loglevel one (option -l 1 for most commands) to show debugging
-info. Almost all paraslash executables have a brief online help which
-is displayed by using the -h switch.
+Use the debug loglevel (option -l debug for most commands) to show
+debugging info. Almost all paraslash executables have a brief online
+help which is displayed by using the -h switch. The --detailed-help
+option prints the full help text.
para_fsck tries to fix your database. Use --force (even if your name
-isn't Luke), to clean up after a crash. However, first make sure
+isn't Luke) to clean up after a crash. However, first make sure
para_server isn't running before executing para_fsck if para_fsck
complains about busy (dirty) tables. para_fsck also contains an option
-to dump the contents of your the contents of the database to the file
-system.
+to dump the contents of the database to the file system.
If you don't mind to recreate your database you can start
from scratch by removing the entire database directory, i.e.
projects / paraslash.git / blobdiff