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package PDL::Audio::Pitches; |
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require Exporter; |
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@ISA = qw(Exporter); |
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$VERSION = 1.0; |
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|
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=head1 NAME |
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PDL::Audio::Pitches - All the standard musical pitch names. |
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=head1 SYNOPSIS |
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|
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use PDL::Audio::Pitches; |
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print a4; # prints 440 |
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print bs3; # prints 261.63 |
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=head1 DESCRIPTION |
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|
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This module defines (and exports by default(!)) all standard pitch names: |
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C<cdefgab> with trailing octave, e.g. C<a4>, C<g3>, C<c0>, C<a8>, |
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C<interleaved "f" and "s", e.g. as4>, C<bf3>, C<fs6>. |
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|
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=cut |
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=head1 AUTHOR |
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|
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Marc Lehmann <schmorp@schmorp.de> |
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=head1 SEE ALSO |
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perl(1), L<PDL>, L<PDL::Audio>. |
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=cut |
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my $base = 440.0 / (2 ** 4.75); |
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sub gen($$$) { |
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my ($o,$p,$i) = @_; |
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my $note = "$p$o"; |
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my $hz = $base * (2 ** ($o + $i/12)); |
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eval "sub $note (){ $hz }"; |
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push @EXPORT, $note; |
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} |
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for my $o (0..8) { |
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gen $o, 'c', 0; gen $o, 'cs', 1; gen $o, 'df', 1; |
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gen $o, 'd', 2; gen $o, 'ds', 3; gen $o, 'ef', 3; |
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gen $o, 'e', 4; gen $o, 'ff', 4; gen $o, 'es', 5; |
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gen $o, 'f', 5; gen $o, 'fs', 6; gen $o, 'gf', 6; |
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gen $o, 'g', 7; gen $o, 'gs', 8; gen $o, 'af', 8; |
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gen $o, 'a', 9; gen $o, 'as',10; gen $o, 'bf',10; |
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gen $o, 'b',11; gen $o, 'cf',-1; gen $o, 'bs',12; |
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} |
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1; |