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diff --git a/src/silx/gui/plot/items/image_aggregated.py b/src/silx/gui/plot/items/image_aggregated.py
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+# /*##########################################################################
+#
+# Copyright (c) 2021-2023 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 the :class:`ImageDataAggregated` items of the :class:`Plot`.
+"""
+
+__authors__ = ["T. Vincent"]
+__license__ = "MIT"
+__date__ = "07/07/2021"
+
+import enum
+import logging
+from typing import Tuple, Union
+import warnings
+
+import numpy
+
+from ....utils.enum import Enum as _Enum
+from ....utils.proxy import docstring
+from .axis import Axis
+from .core import ItemChangedType
+from .image import ImageDataBase
+from ._pick import PickingResult
+
+
+_logger = logging.getLogger(__name__)
+
+
+class ImageDataAggregated(ImageDataBase):
+    """Item displaying an image as a density map."""
+
+    @enum.unique
+    class Aggregation(_Enum):
+        NONE = "none"
+        "Do not aggregate data, display as is (default)"
+
+        MAX = "max"
+        "Aggregates elements with max (ignore NaNs)"
+
+        MEAN = "mean"
+        "Aggregates elements with mean (ignore NaNs)"
+
+        MIN = "min"
+        "Aggregates elements with min (ignore NaNs)"
+
+    def __init__(self):
+        super().__init__()
+        self.__cacheLODData = {}
+        self.__currentLOD = 0, 0
+        self.__aggregationMode = self.Aggregation.NONE
+
+    def setAggregationMode(self, mode: Union[str, Aggregation]):
+        """Set the aggregation method used to reduce the data to screen resolution.
+
+        :param Aggregation mode: The aggregation method
+        """
+        aggregationMode = self.Aggregation.from_value(mode)
+        if aggregationMode != self.__aggregationMode:
+            self.__aggregationMode = aggregationMode
+            self.__cacheLODData = {}  # Clear cache
+            self._updated(ItemChangedType.VISUALIZATION_MODE)
+
+    def getAggregationMode(self) -> Aggregation:
+        """Returns the currently used aggregation method."""
+        return self.__aggregationMode
+
+    def _addBackendRenderer(self, backend):
+        """Update backend renderer"""
+        plot = self.getPlot()
+        assert plot is not None
+        if not self._isPlotLinear(plot):
+            # Do not render with non linear scales
+            return None
+
+        data = self.getData(copy=False)
+        if data.size == 0:
+            return None  # No data to display
+
+        aggregationMode = self.getAggregationMode()
+        if aggregationMode == self.Aggregation.NONE:  # Pass data as it is
+            displayedData = data
+            scale = self.getScale()
+
+        else:  # Aggregate data according to level of details
+            if aggregationMode == self.Aggregation.MAX:
+                aggregator = numpy.nanmax
+            elif aggregationMode == self.Aggregation.MEAN:
+                aggregator = numpy.nanmean
+            elif aggregationMode == self.Aggregation.MIN:
+                aggregator = numpy.nanmin
+            else:
+                _logger.error("Unsupported aggregation mode")
+                return None
+
+            lodx, lody = self._getLevelOfDetails()
+
+            if (lodx, lody) not in self.__cacheLODData:
+                height, width = data.shape
+                with warnings.catch_warnings():
+                    warnings.simplefilter("ignore", category=RuntimeWarning)
+                    self.__cacheLODData[(lodx, lody)] = aggregator(
+                        data[
+                            : (height // lody) * lody, : (width // lodx) * lodx
+                        ].reshape(height // lody, lody, width // lodx, lodx),
+                        axis=(1, 3),
+                    )
+
+            self.__currentLOD = lodx, lody
+            displayedData = self.__cacheLODData[self.__currentLOD]
+
+            sx, sy = self.getScale()
+            scale = sx * lodx, sy * lody
+
+        return backend.addImage(
+            displayedData,
+            origin=self.getOrigin(),
+            scale=scale,
+            colormap=self._getColormapForRendering(),
+            alpha=self.getAlpha(),
+        )
+
+    def _getPixelSizeInData(self, axis="left"):
+        """Returns the size of a pixel in plot data coordinates
+
+        :param str axis: Y axis to use in: 'left' (default), 'right'
+        :return:
+            Size (width, height) of a Qt pixel in data coordinates.
+            Size is None if it cannot be computed
+        :rtype: Union[List[float],None]
+        """
+        assert axis in ("left", "right")
+        plot = self.getPlot()
+        if plot is None:
+            return None
+
+        xaxis = plot.getXAxis()
+        yaxis = plot.getYAxis(axis)
+
+        if xaxis.getScale() != Axis.LINEAR or yaxis.getScale() != Axis.LINEAR:
+            raise RuntimeError("Only available with linear axes")
+
+        xmin, xmax = xaxis.getLimits()
+        ymin, ymax = yaxis.getLimits()
+        width, height = plot.getPlotBoundsInPixels()[2:]
+        if width == 0 or height == 0:
+            return None
+        else:
+            return (xmax - xmin) / width, (ymax - ymin) / height
+
+    def _getLevelOfDetails(self) -> Tuple[int, int]:
+        """Return current level of details the image is displayed with."""
+        plot = self.getPlot()
+        if plot is None or not self._isPlotLinear(plot):
+            return 1, 1  # Fallback to bas LOD
+
+        sx, sy = self.getScale()
+        xUnitPerPixel, yUnitPerPixel = self._getPixelSizeInData()
+        lodx = max(1, int(numpy.ceil(xUnitPerPixel / sx)))
+        lody = max(1, int(numpy.ceil(yUnitPerPixel / sy)))
+        return lodx, lody
+
+    @docstring(ImageDataBase)
+    def setData(self, data, copy=True):
+        self.__cacheLODData = {}  # Reset cache
+        super().setData(data)
+
+    @docstring(ImageDataBase)
+    def _setPlot(self, plot):
+        """Refresh image when plot limits change"""
+        previousPlot = self.getPlot()
+        if previousPlot is not None:
+            for axis in (previousPlot.getXAxis(), previousPlot.getYAxis()):
+                axis.sigLimitsChanged.disconnect(self.__plotLimitsChanged)
+
+        super()._setPlot(plot)
+
+        if plot is not None:
+            for axis in (plot.getXAxis(), plot.getYAxis()):
+                axis.sigLimitsChanged.connect(self.__plotLimitsChanged)
+
+    def __plotLimitsChanged(self):
+        """Trigger update if level of details has changed"""
+        if (
+            self.getAggregationMode() != self.Aggregation.NONE
+            and self.__currentLOD != self._getLevelOfDetails()
+        ):
+            self._updated()
+
+    @docstring(ImageDataBase)
+    def pick(self, x, y):
+        result = super().pick(x, y)
+        if result is None:
+            return None
+
+        # Compute indices in initial data
+        plot = self.getPlot()
+        if plot is None:
+            return None
+        dataPos = plot.pixelToData(x, y, axis="left", check=True)
+        if dataPos is None:
+            return None  # Outside plot area
+
+        ox, oy = self.getOrigin()
+        sx, sy = self.getScale()
+        col = int((dataPos[0] - ox) / sx)
+        row = int((dataPos[1] - oy) / sy)
+        height, width = self.getData(copy=False).shape[:2]
+        if 0 <= col < width and 0 <= row < height:
+            return PickingResult(self, ((row,), (col,)))
+        return None