[Python-checkins] cpython (2.7): Issue #1575020: Fixed support of 24-bit wave files on big-endian platforms.
serhiy.storchaka
python-checkins at python.org
Sat Nov 9 22:17:11 CET 2013
http://hg.python.org/cpython/rev/5fbcb4aa48fa
changeset: 87024:5fbcb4aa48fa
branch: 2.7
parent: 87021:be8f9beca8aa
user: Serhiy Storchaka <storchaka at gmail.com>
date: Sat Nov 09 23:09:44 2013 +0200
summary:
Issue #1575020: Fixed support of 24-bit wave files on big-endian platforms.
files:
Lib/test/test_wave.py | 3 ---
Lib/wave.py | 21 +++++++++++++--------
Misc/NEWS | 2 ++
3 files changed, 15 insertions(+), 11 deletions(-)
diff --git a/Lib/test/test_wave.py b/Lib/test/test_wave.py
--- a/Lib/test/test_wave.py
+++ b/Lib/test/test_wave.py
@@ -49,9 +49,6 @@
frames = audiotests.byteswap2(frames)
- at unittest.skipIf(sys.byteorder == 'big',
- '24-bit wave files are supported only on little-endian '
- 'platforms')
class WavePCM24Test(audiotests.AudioWriteTests,
audiotests.AudioTestsWithSourceFile,
unittest.TestCase):
diff --git a/Lib/wave.py b/Lib/wave.py
--- a/Lib/wave.py
+++ b/Lib/wave.py
@@ -82,14 +82,15 @@
_array_fmts = None, 'b', 'h', None, 'i'
-# Determine endian-ness
import struct
-if struct.pack("h", 1) == "\000\001":
- big_endian = 1
-else:
- big_endian = 0
+import sys
+from chunk import Chunk
-from chunk import Chunk
+def _byteswap3(data):
+ ba = bytearray(data)
+ ba[::3] = data[2::3]
+ ba[2::3] = data[::3]
+ return bytes(ba)
class Wave_read:
"""Variables used in this class:
@@ -231,7 +232,7 @@
self._data_seek_needed = 0
if nframes == 0:
return ''
- if self._sampwidth > 1 and big_endian:
+ if self._sampwidth in (2, 4) and sys.byteorder == 'big':
# unfortunately the fromfile() method does not take
# something that only looks like a file object, so
# we have to reach into the innards of the chunk object
@@ -252,6 +253,8 @@
data = data.tostring()
else:
data = self._data_chunk.read(nframes * self._framesize)
+ if self._sampwidth == 3 and sys.byteorder == 'big':
+ data = _byteswap3(data)
if self._convert and data:
data = self._convert(data)
self._soundpos = self._soundpos + len(data) // (self._nchannels * self._sampwidth)
@@ -419,7 +422,7 @@
nframes = len(data) // (self._sampwidth * self._nchannels)
if self._convert:
data = self._convert(data)
- if self._sampwidth > 1 and big_endian:
+ if self._sampwidth in (2, 4) and sys.byteorder == 'big':
import array
data = array.array(_array_fmts[self._sampwidth], data)
assert data.itemsize == self._sampwidth
@@ -427,6 +430,8 @@
data.tofile(self._file)
self._datawritten = self._datawritten + len(data) * self._sampwidth
else:
+ if self._sampwidth == 3 and sys.byteorder == 'big':
+ data = _byteswap3(data)
self._file.write(data)
self._datawritten = self._datawritten + len(data)
self._nframeswritten = self._nframeswritten + nframes
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,8 @@
Library
-------
+- Issue #1575020: Fixed support of 24-bit wave files on big-endian platforms.
+
- Issue #19480: HTMLParser now accepts all valid start-tag names as defined
by the HTML5 standard.
--
Repository URL: http://hg.python.org/cpython
More information about the Python-checkins
mailing list