45 lines
1.3 KiB
Python
45 lines
1.3 KiB
Python
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"""Interpret sun audio headers."""
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MAGIC = '.snd'
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class error(Exception):
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pass
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def get_long_be(s):
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"""Convert a 4-char value to integer."""
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return (ord(s[0])<<24) | (ord(s[1])<<16) | (ord(s[2])<<8) | ord(s[3])
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def gethdr(fp):
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"""Read a sound header from an open file."""
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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 = get_long_be(fp.read(4))
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data_size = get_long_be(fp.read(4))
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encoding = get_long_be(fp.read(4))
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sample_rate = get_long_be(fp.read(4))
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channels = get_long_be(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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def printhdr(file):
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"""Read and print the sound header of a named 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: ', repr(info)
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