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diff --git a/src/silx/gui/plot3d/utils/mng.py b/src/silx/gui/plot3d/utils/mng.py
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+++ b/src/silx/gui/plot3d/utils/mng.py
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+# coding: utf-8
+# /*##########################################################################
+#
+# Copyright (c) 2016-2020 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 basic writing Mulitple-image Network Graphics files.
+
+It only supports RGB888 images of the same shape stored as
+MNG-VLC (very low complexity) format.
+"""
+
+from __future__ import absolute_import
+
+__authors__ = ["T. Vincent"]
+__license__ = "MIT"
+__date__ = "15/12/2016"
+
+
+import logging
+import struct
+import zlib
+
+import numpy
+
+_logger = logging.getLogger(__name__)
+
+
+def _png_chunk(name, data):
+    """Return a PNG chunk
+
+    :param str name: Chunk type
+    :param byte data: Chunk payload
+    """
+    length = struct.pack('>I', len(data))
+    name = [char.encode('ascii') for char in name]
+    chunk = struct.pack('cccc', *name) + data
+    crc = struct.pack('>I', zlib.crc32(chunk) & 0xffffffff)
+    return length + chunk + crc
+
+
+def convert(images, nb_images=0, fps=25):
+    """Convert RGB images to MNG-VLC format.
+
+    See http://www.libpng.org/pub/mng/spec/
+    See http://www.libpng.org/pub/png/book/
+    See http://www.libpng.org/pub/png/spec/1.2/
+
+    :param images: iterator of RGB888 images
+    :type images: iterator of numpy.ndarray of dimension 3
+    :param int nb_images: The number of images indicated in the MNG header
+    :param int fps: The frame rate indicated in the MNG header
+    :return: An iterator of MNG chunks as bytes
+    """
+    first_image = True
+
+    for image in images:
+        if first_image:
+            first_image = False
+
+            height, width = image.shape[:2]
+
+            # MNG signature
+            yield b'\x8aMNG\r\n\x1a\n'
+
+            # MHDR chunk: File header
+            yield _png_chunk('MHDR', struct.pack(
+                ">IIIIIII",
+                width,
+                height,
+                fps,  # ticks
+                nb_images + 1,  # layer count
+                nb_images,  # frame count
+                nb_images,  # play time
+                1))  # profile: MNG-VLC no alpha: only least significant bit 1
+
+        assert image.shape == (height, width, 3)
+        assert image.dtype == numpy.dtype('uint8')
+
+        # IHDR chunk: Image header
+        depth = 8  # 8 bit per channel
+        color_type = 2  # 'truecolor' = RGB
+        interlace = 0  # No
+        yield _png_chunk('IHDR', struct.pack(">IIBBBBB",
+                                             width,
+                                             height,
+                                             depth,
+                                             color_type,
+                                             0, 0, interlace))
+
+        # Add filter 'None' before each scanline
+        prepared_data = b'\x00' + b'\x00'.join(
+            line.tobytes() for line in image)  # TODO optimize that
+        compressed_data = zlib.compress(prepared_data, 8)
+
+        # IDAT chunk: Payload
+        yield _png_chunk('IDAT', compressed_data)
+
+        # IEND chunk: Image footer
+        yield _png_chunk('IEND', b'')
+
+    # MEND chunk: footer
+    yield _png_chunk('MEND', b'')