3 # This file is part of jack_mixer
5 # Copyright (C) 2006 Nedko Arnaudov <nedko@arnaudov.name>
7 # This program is free software; you can redistribute it and/or modify
8 # it under the terms of the GNU General Public License as published by
9 # the Free Software Foundation; version 2 of the License
11 # This program is distributed in the hope that it will be useful,
12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 # GNU General Public License for more details.
16 # You should have received a copy of the GNU General Public License
17 # along with this program; if not, write to the Free Software
18 # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
25 '''Encapsulates scale linear function edge and coefficients for scale = a * dB + b formula'''
26 def __init__(self
, db
, scale
):
29 self
.text
= "%.0f" % math
.fabs(db
)
32 '''Scale abstraction, various scale implementation derive from this class'''
33 def __init__(self
, scale_id
, description
):
35 self
.scale_id
= scale_id
36 self
.description
= description
37 self
.scale
= jack_mixer_c
.scale_create()
39 def add_threshold(self
, db
, scale
, is_mark
):
40 jack_mixer_c
.scale_add_threshold(self
.scale
, db
, scale
)
42 self
.marks
.append(mark(db
, scale
))
44 def calculate_coefficients(self
):
45 jack_mixer_c
.scale_calculate_coefficients(self
.scale
)
47 def db_to_scale(self
, db
):
48 '''Convert dBFS value to number in range 0.0-1.0 used in GUI'''
49 #print "db_to_scale(%f)" % db
50 return jack_mixer_c
.scale_db_to_scale(self
.scale
, db
)
52 def scale_to_db(self
, scale
):
53 '''Convert number in range 0.0-1.0 used in GUI to dBFS value'''
54 return jack_mixer_c
.scale_scale_to_db(self
.scale
, scale
)
56 def add_mark(self
, db
):
57 self
.marks
.append(mark(db
, -1.0))
62 def scale_marks(self
):
65 i
.scale
= self
.db_to_scale(i
.db
)
67 # IEC 60268-18 Peak programme level meters - Digital audio peak level meter
68 # Adapted from meterpridge, may be wrong, I'm not buying standards, event if they cost $45
69 # If someone has the standart, please eighter share it with me or fix the code.
71 '''IEC 60268-18 Peak programme level meters - Digital audio peak level meter'''
73 base
.__init
__(self
, "iec_268", "IEC 60268-18 Peak programme level meters - Digital audio peak level meter")
74 self
.add_threshold(-70.0, 0.0, False)
75 self
.add_threshold(-60.0, 0.05, True)
76 self
.add_threshold(-50.0, 0.075, True)
77 self
.add_threshold(-40.0, 0.15, True)
79 self
.add_threshold(-30.0, 0.3, True)
81 self
.add_threshold(-20.0, 0.5, True)
85 self
.add_threshold(0.0, 1.0, True)
86 self
.calculate_coefficients()
89 class iec_268_minimalistic(base
):
90 '''IEC 60268-18 Peak programme level meters - Digital audio peak level meter, fewer marks'''
92 base
.__init
__(self
, "iec_268_minimalistic", "IEC 60268-18 Peak programme level meters - Digital audio peak level meter, fewer marks")
93 self
.add_threshold(-70.0, 0.0, False)
94 self
.add_threshold(-60.0, 0.05, True)
95 self
.add_threshold(-50.0, 0.075, False)
96 self
.add_threshold(-40.0, 0.15, True)
97 self
.add_threshold(-30.0, 0.3, True)
98 self
.add_threshold(-20.0, 0.5, True)
100 self
.add_threshold(0.0, 1.0, True)
101 self
.calculate_coefficients()
104 class linear_70dB(base
):
105 '''Linear scale with range from -70 to 0 dBFS'''
107 base
.__init
__(self
, "linear_70dB", "Linear scale with range from -70 to 0 dBFS")
108 self
.add_threshold(-70.0, 0.0, False)
119 self
.add_threshold(0.0, 1.0, True)
120 self
.calculate_coefficients()
123 class linear_30dB(base
):
124 '''Linear scale with range from -30 to +30 dBFS'''
126 base
.__init
__(self
, "linear_30dB", "Linear scale with range from -30 to +30 dBFS")
127 self
.add_threshold(-30.0, 0.0, False)
128 self
.add_threshold(+30.0, 1.0, True)
129 self
.calculate_coefficients()
132 def scale_test1(scale
):
133 for i
in range(-97 * 2, 1, 1):
135 print "%5.1f dB maps to %f" % (db
, scale
.db_to_scale(db
))
137 def scale_test2(scale
):
140 print "%.2f maps to %.1f dB" % (s
, scale
.scale_to_db(s
))
142 def print_db_to_scale(db
):
143 print "%-.1f dB maps to %f" % (db
, scale
.db_to_scale(db
))
145 def scale_test3(scale
):
146 print_db_to_scale(+77.0)
147 print_db_to_scale(+7.0)
148 print_db_to_scale(0.0)
149 print_db_to_scale(-107.0)
151 #scale = linear_30dB()