Issue #1575020: Fixed support of 24-bit wave files on big-endian platforms.
diff --git a/Lib/test/test_wave.py b/Lib/test/test_wave.py
index b4413c6..cf069ae 100644
--- a/Lib/test/test_wave.py
+++ b/Lib/test/test_wave.py
@@ -49,9 +49,6 @@
frames = audiotests.byteswap2(frames)
-@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
index 0e6628b..e723423 100644
--- a/Lib/wave.py
+++ b/Lib/wave.py
@@ -87,6 +87,12 @@
from chunk import Chunk
from collections import namedtuple
+def _byteswap3(data):
+ ba = bytearray(data)
+ ba[::3] = data[2::3]
+ ba[2::3] = data[::3]
+ return bytes(ba)
+
_wave_params = namedtuple('_wave_params',
'nchannels sampwidth framerate nframes comptype compname')
@@ -237,7 +243,7 @@
self._data_seek_needed = 0
if nframes == 0:
return b''
- if self._sampwidth > 1 and sys.byteorder == 'big':
+ 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
@@ -258,6 +264,8 @@
data = data.tobytes()
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)
@@ -431,7 +439,7 @@
nframes = len(data) // (self._sampwidth * self._nchannels)
if self._convert:
data = self._convert(data)
- if self._sampwidth > 1 and sys.byteorder == 'big':
+ 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
@@ -439,6 +447,8 @@
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
index 107d084..e780fdf 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -34,6 +34,8 @@
Library
-------
+- Issue #1575020: Fixed support of 24-bit wave files on big-endian platforms.
+
- Issue #19378: Fixed a number of cases in the dis module where the new
"file" parameter was not being honoured correctly