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diff --git a/src/silx/gui/utils/image.py b/src/silx/gui/utils/image.py
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+# coding: utf-8
+# /*##########################################################################
+#
+# Copyright (c) 2017-2021 European Synchrotron Radiation Facility
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#
+# ###########################################################################*/
+"""This module provides conversions between numpy.ndarray and QImage
+
+- :func:`convertArrayToQImage`
+- :func:`convertQImageToArray`
+"""
+
+from __future__ import division
+
+
+__authors__ = ["T. Vincent"]
+__license__ = "MIT"
+__date__ = "04/09/2018"
+
+
+import sys
+import numpy
+from numpy.lib.stride_tricks import as_strided as _as_strided
+
+from .. import qt
+
+
+def convertArrayToQImage(array):
+    """Convert an array-like image to a QImage.
+
+    The created QImage is using a copy of the array data.
+
+    Limitation: Only RGB or RGBA images with 8 bits per channel are supported.
+
+    :param array: Array-like image data of shape (height, width, channels)
+       Channels are expected to be either RGB or RGBA.
+    :type array: numpy.ndarray of uint8
+    :return: Corresponding Qt image with RGB888 or ARGB32 format.
+    :rtype: QImage
+    """
+    array = numpy.array(array, copy=False, order='C', dtype=numpy.uint8)
+
+    if array.ndim != 3 or array.shape[2] not in (3, 4):
+        raise ValueError(
+            'Image must be a 3D array with 3 or 4 channels per pixel')
+
+    if array.shape[2] == 4:
+        format_ = qt.QImage.Format_ARGB32
+        # RGBA -> ARGB + take care of endianness
+        if sys.byteorder == 'little':  # RGBA -> BGRA
+            array = array[:, :, (2, 1, 0, 3)]
+        else:  # big endian: RGBA -> ARGB
+            array = array[:, :, (3, 0, 1, 2)]
+
+        array = numpy.array(array, order='C')  # Make a contiguous array
+
+    else:  # array.shape[2] == 3
+        format_ = qt.QImage.Format_RGB888
+
+    height, width, depth = array.shape
+    qimage = qt.QImage(
+        array.data,
+        width,
+        height,
+        array.strides[0],  # bytesPerLine
+        format_)
+
+    return qimage.copy()  # Making a copy of the image and its data
+
+
+def convertQImageToArray(image):
+    """Convert a QImage to a numpy array.
+
+    If QImage format is not Format_RGB888, Format_RGBA8888 or Format_ARGB32,
+    it is first converted to one of this format depending on
+    the presence of an alpha channel.
+
+    The created numpy array is using a copy of the QImage data.
+
+    :param QImage image: The QImage to convert.
+    :return: The image array of RGB or RGBA channels of shape
+        (height, width, channels (3 or 4))
+    :rtype: numpy.ndarray of uint8
+    """
+    rgba8888 = getattr(qt.QImage, 'Format_RGBA8888', None)  # Only in Qt5
+
+    # Convert to supported format if needed
+    if image.format() not in (qt.QImage.Format_ARGB32,
+                              qt.QImage.Format_RGB888,
+                              rgba8888):
+        if image.hasAlphaChannel():
+            image = image.convertToFormat(
+                rgba8888 if rgba8888 is not None else qt.QImage.Format_ARGB32)
+        else:
+            image = image.convertToFormat(qt.QImage.Format_RGB888)
+
+    format_ = image.format()
+    channels = 3 if format_ == qt.QImage.Format_RGB888 else 4
+
+    ptr = image.bits()
+    if qt.BINDING == 'PyQt5':
+        ptr.setsize(image.byteCount())
+    elif qt.BINDING in ('PySide2', 'PySide6'):
+        ptr = ptr.tobytes()
+    else:
+        raise RuntimeError("Unsupported Qt binding: %s" % qt.BINDING)
+
+    # Create an array view on QImage internal data
+    view = _as_strided(
+        numpy.frombuffer(ptr, dtype=numpy.uint8),
+        shape=(image.height(), image.width(), channels),
+        strides=(image.bytesPerLine(), channels, 1))
+
+    if format_ == qt.QImage.Format_ARGB32:
+        # Convert from ARGB to RGBA
+        # Not a byte-ordered format: do care about endianness
+        if sys.byteorder == 'little':  # BGRA -> RGBA
+            view = view[:, :, (2, 1, 0, 3)]
+        else:  # big endian: ARGB -> RGBA
+            view = view[:, :, (1, 2, 3, 0)]
+
+    # Format_RGB888 and Format_RGBA8888 do not need reshuffling channels:
+    # They are byte-ordered and already in the right order
+
+    return numpy.array(view, copy=True, order='C')