/Mac/Demo/sound/morselib.py

  1"""Translate text strings to Morse code"""
  2
  3FRAMERATE = 22050
  4SAMPWIDTH = 2
  5
  6BASEFREQ = 441
  7OCTAVE = 2
  8
  9DOT = 30
 10DAH = 80
 11
 12morsetab = {
 13        'a': '.-',
 14        'b': '-...',
 15        'c': '-.-.',
 16        'd': '-..',
 17        'e': '.',
 18        'f': '..-.',
 19        'g': '--.',
 20        'h': '....',
 21        'i': '..',
 22        'j': '.---',
 23        'k': '-.-',
 24        'l': '.-..',
 25        'm': '--',
 26        'n': '-.',
 27        'o': '---',
 28        'p': '.--.',
 29        'q': '--.-',
 30        'r': '.-.',
 31        's': '...',
 32        't': '-',
 33        'u': '..-',
 34        'v': '...-',
 35        'w': '.--',
 36        'x': '-..-',
 37        'y': '-.--',
 38        'z': '--..',
 39        '0': '-----',
 40        '1': '.----',
 41        '2': '..---',
 42        '3': '...--',
 43        '4': '....-',
 44        '5': '.....',
 45        '6': '-....',
 46        '7': '--...',
 47        '8': '---..',
 48        '9': '----.',
 49        ',': '--..--',
 50        '.': '.-.-.-',
 51        '?': '..--..',
 52        ';': '-.-.-.',
 53        ':': '---...',
 54        "'": '.----.',
 55        '-': '-....-',
 56        '/': '-..-.',
 57        '(': '-.--.-',
 58        ')': '-.--.-', # XXX same as code for '(' ???
 59        '_': '..--.-',
 60        ' ': ' '
 61}
 62
 63def morsecode(s):
 64    from string import lower
 65    m = ''
 66    for c in s:
 67        c = lower(c)
 68        if morsetab.has_key(c):
 69            c = morsetab[c] + ' '
 70        else:
 71            c = '? '
 72        m = m + c
 73    return m
 74
 75
 76class BaseMorse:
 77    "base class for morse transmissions"
 78
 79    def __init__(self):
 80        "constructor"
 81        self.dots = DOT
 82        self.dahs = DAH
 83
 84    def noise(self, duration):
 85        "beep for given duration"
 86        pass
 87
 88    def pause(self, duration):
 89        "pause for given duration"
 90        pass
 91
 92    def dot(self):
 93        "short beep"
 94        self.noise(self.dots)
 95
 96    def dah(self):
 97        "long beep"
 98        self.noise(self.dahs)
 99
100    def pdot(self):
101        "pause as long as a dot"
102        self.pause(self.dots)
103
104    def pdah(self):
105        "pause as long as a dah"
106        self.pause(self.dahs)
107
108    def sendmorse(self, s):
109        for c in s:
110            if c == '.': self.dot()
111            elif c == '-': self.dah()
112            else: self.pdah()
113            self.pdot()
114
115    def sendascii(self, s):
116        self.sendmorse(morsecode(s))
117
118    def send(self, s):
119        self.sendascii(s)
120
121
122import Audio_mac
123class MyAudio(Audio_mac.Play_Audio_mac):
124    def _callback(self, *args):
125        if hasattr(self, 'usercallback'): self.usercallback()
126        apply(Audio_mac.Play_Audio_mac._callback, (self,) + args)
127
128
129class MacMorse(BaseMorse):
130    "Mac specific class to play Morse code"
131
132    def __init__(self):
133        BaseMorse.__init__(self)
134        self.dev = MyAudio()
135        self.dev.setoutrate(FRAMERATE)
136        self.dev.setsampwidth(SAMPWIDTH)
137        self.dev.setnchannels(1)
138        self.dev.usercallback = self.usercallback
139        sinewave = ''
140        n = int(FRAMERATE / BASEFREQ)
141        octave = OCTAVE
142        from math import sin, pi
143        for i in range(n):
144            val = int(sin(2 * pi * i * octave / n) * 0x7fff)
145            sample = chr((val >> 8) & 255) + chr(val & 255)
146            sinewave = sinewave + sample[:SAMPWIDTH]
147        self.sinewave = sinewave
148        self.silence = '\0' * (n*SAMPWIDTH)
149        self.morsequeue = ''
150
151    def __del__(self):
152        self.close()
153
154    def close(self):
155        self.dev = None
156
157    def pause(self, duration):
158        self.dev.writeframes(self.silence * duration)
159
160    def noise(self, duration):
161        self.dev.writeframes(self.sinewave * duration)
162
163    def sendmorse(self, s):
164        self.morsequeue = self.morsequeue + s
165        self.dev.usercallback()
166        self.dev.usercallback()
167        self.dev.usercallback()
168
169    def usercallback(self):
170        if self.morsequeue:
171            c, self.morsequeue = self.morsequeue[0], self.morsequeue[1:]
172            if c == '.': self.dot()
173            elif c == '-': self.dah()
174            else: self.pdah()
175            self.pdot()
176
177
178def test():
179    m = MacMorse()
180    while 1:
181        try:
182            line = raw_input('Morse line: ')
183        except (EOFError, KeyboardInterrupt):
184            break
185        m.send(line)
186        while m.morsequeue: pass
187
188test()