"""Convert "arbitrary" sound files to AIFF (Apple and SGI's audio format).
Input may be compressed.
Uncompressed file type may be AIFF, WAV, VOC, 8SVX, NeXT/Sun, and others.
An exception is raised if the file is not of a recognized type.
Returned filename is either the input filename or a temporary filename;
in the latter case the caller must ensure that it is removed.
Other temporary files used are removed by the function.
"""
import os
import tempfile
import pipes
import sndhdr
__all__ = ["error", "toaiff"]
table = {}
t = pipes.Template()
t.append('sox -t au - -t aiff -r 8000 -', '--')
table['au'] = t
# XXX The following is actually sub-optimal.
# XXX The HCOM sampling rate can be 22k, 22k/2, 22k/3 or 22k/4.
# XXX We must force the output sampling rate else the SGI won't play
# XXX files sampled at 5.5k or 7.333k; however this means that files
# XXX sampled at 11k are unnecessarily expanded.
# XXX Similar comments apply to some other file types.
t = pipes.Template()
t.append('sox -t hcom - -t aiff -r 22050 -', '--')
table['hcom'] = t
t = pipes.Template()
t.append('sox -t voc - -t aiff -r 11025 -', '--')
table['voc'] = t
t = pipes.Template()
t.append('sox -t wav - -t aiff -', '--')
table['wav'] = t
t = pipes.Template()
t.append('sox -t 8svx - -t aiff -r 16000 -', '--')
table['8svx'] = t
t = pipes.Template()
t.append('sox -t sndt - -t aiff -r 16000 -', '--')
table['sndt'] = t
t = pipes.Template()
t.append('sox -t sndr - -t aiff -r 16000 -', '--')
table['sndr'] = t
uncompress = pipes.Template()
uncompress.append('uncompress', '--')
class error(Exception):
pass
def toaiff(filename):
temps = []
ret = None
try:
ret = _toaiff(filename, temps)
finally:
for temp in temps[:]:
if temp != ret:
try:
os.unlink(temp)
except os.error:
pass
temps.remove(temp)
return ret
def _toaiff(filename, temps):
if filename[-2:] == '.Z':
(fd, fname) = tempfile.mkstemp()
os.close(fd)
temps.append(fname)
sts = uncompress.copy(filename, fname)
if sts:
raise error(filename + ': uncompress failed')
else:
fname = filename
try:
ftype = sndhdr.whathdr(fname)
if ftype:
ftype = ftype[0] # All we're interested in
except IOError as msg:
if type(msg) == type(()) and len(msg) == 2 and \
type(msg.args[0]) == type(0) and type(msg.args[1]) == type(''):
msg = msg.args[1]
if type(msg) != type(''):
msg = repr(msg)
raise error(filename + ': ' + msg)
if ftype == 'aiff':
return fname
if ftype is None or not ftype in table:
raise error('%s: unsupported audio file type %r' % (filename, ftype))
(fd, temp) = tempfile.mkstemp()
os.close(fd)
temps.append(temp)
sts = table[ftype].copy(fname, temp)
if sts:
raise error(filename + ': conversion to aiff failed')
return temp
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