cpython/Lib/toaiff.py

104 lines
2.6 KiB
Python
Raw Normal View History

"""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
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', '--')
error = 'toaiff.error' # Exception
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':
fname = tempfile.mktemp()
temps.append(fname)
sts = uncompress.copy(filename, fname)
if sts:
raise error, filename + ': uncomress failed'
else:
fname = filename
try:
ftype = sndhdr.whathdr(fname)
if ftype:
ftype = ftype[0] # All we're interested in
except IOError:
if type(msg) == type(()) and len(msg) == 2 and \
type(msg[0]) == type(0) and type(msg[1]) == type(''):
msg = msg[1]
if type(msg) <> type(''):
msg = `msg`
raise error, filename + ': ' + msg
if ftype == 'aiff':
return fname
if ftype == None or not table.has_key(ftype):
raise error, \
filename + ': unsupported audio file type ' + `ftype`
temp = tempfile.mktemp()
temps.append(temp)
sts = table[ftype].copy(fname, temp)
if sts:
raise error, filename + ': conversion to aiff failed'
return temp