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55 lines
1.3 KiB
Python
55 lines
1.3 KiB
Python
# Module 'sunaudio' -- interpret sun audio headers
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import audio
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MAGIC = '.snd'
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error = 'sunaudio sound header conversion error'
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# convert a 4-char value to integer
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def c2i(data):
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if type(data) <> type('') or len(data) <> 4:
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raise error, 'c2i: bad arg (not string[4])'
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bytes = audio.chr2num(data)
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for i in (1, 2, 3):
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if bytes[i] < 0:
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bytes[i] = bytes[i] + 256
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return ((bytes[0]*256 + bytes[1])*256 + bytes[2])*256 + bytes[3]
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# read a sound header from an open file
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def gethdr(fp):
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if fp.read(4) <> MAGIC:
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raise error, 'gethdr: bad magic word'
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hdr_size = c2i(fp.read(4))
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data_size = c2i(fp.read(4))
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encoding = c2i(fp.read(4))
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sample_rate = c2i(fp.read(4))
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channels = c2i(fp.read(4))
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excess = hdr_size - 24
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if excess < 0:
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raise error, 'gethdr: bad hdr_size'
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if excess > 0:
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info = fp.read(excess)
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else:
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info = ''
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return (data_size, encoding, sample_rate, channels, info)
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# read and print the sound header of a named file
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def printhdr(file):
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hdr = gethdr(open(file, 'r'))
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data_size, encoding, sample_rate, channels, info = hdr
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while info[-1:] = '\0':
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info = info[:-1]
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print 'File name: ', file
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print 'Data size: ', data_size
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print 'Encoding: ', encoding
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print 'Sample rate:', sample_rate
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print 'Channels: ', channels
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print 'Info: ', `info`
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