# -*- coding: utf-8 -*-
from __future__ import division
import numpy
from .GraphicsObject import GraphicsObject
from .. import debug as debug
from .. import functions as fn
from .. import getConfigOption
from ..Point import Point
from ..Qt import QtGui, QtCore
from ..util.cupy_helper import getCupy
try:
from collections.abc import Callable
except ImportError:
# fallback for python < 3.3
from collections import Callable
translate = QtCore.QCoreApplication.translate
__all__ = ['ImageItem']
[docs]class ImageItem(GraphicsObject):
"""
**Bases:** :class:`GraphicsObject <pyqtgraph.GraphicsObject>`
"""
# Overall description of ImageItem (including examples) moved to documentation text
sigImageChanged = QtCore.Signal()
sigRemoveRequested = QtCore.Signal(object) # self; emitted when 'remove' is selected from context menu
[docs] def __init__(self, image=None, **kargs):
"""
See :func:`~pyqtgraph.ImageItem.setOpts` for further keyword arguments and
and :func:`~pyqtgraph.ImageItem.setImage` for information on supported formats.
Parameters
----------
image: array
Image data
"""
GraphicsObject.__init__(self)
self.menu = None
self.image = None ## original image data
self.qimage = None ## rendered image for display
self.paintMode = None
self.levels = None ## [min, max] or [[redMin, redMax], ...]
self.lut = None
self.autoDownsample = False
self._lastDownsample = (1, 1)
self._processingBuffer = None
self._displayBuffer = None
self._renderRequired = True
self._unrenderable = False
self._xp = None # either numpy or cupy, to match the image data
self._defferedLevels = None
self.axisOrder = getConfigOption('imageAxisOrder')
self._dataTransform = self._inverseDataTransform = None
self._update_data_transforms( self.axisOrder ) # install initial transforms
# In some cases, we use a modified lookup table to handle both rescaling
# and LUT more efficiently
self._effectiveLut = None
self.drawKernel = None
self.border = None
self.removable = False
if image is not None:
self.setImage(image, **kargs)
else:
self.setOpts(**kargs)
[docs] def setCompositionMode(self, mode):
"""
Change the composition mode of the item. This is useful when overlaying
multiple items.
Parameters
----------
mode : ``QtGui.QPainter.CompositionMode``
Composition of the item, often used when overlaying items. Common
options include:
``QPainter.CompositionMode.CompositionMode_SourceOver`` (Default)
Image replaces the background if it is opaque. Otherwise, it uses
the alpha channel to blend the image with the background.
``QPainter.CompositionMode.CompositionMode_Overlay`` Image color is
mixed with the background color to reflect the lightness or
darkness of the background
``QPainter.CompositionMode.CompositionMode_Plus`` Both the alpha
and color of the image and background pixels are added together.
``QPainter.CompositionMode.CompositionMode_Plus`` The output is the
image color multiplied by the background.
See ``QPainter::CompositionMode`` in the Qt Documentation for more
options and details
"""
self.paintMode = mode
self.update()
[docs] def setBorder(self, b):
"""
Defines the border drawn around the image. Accepts all arguments supported by
:func:`~pyqtgraph.functions.mkPen`.
"""
self.border = fn.mkPen(b)
self.update()
def width(self):
if self.image is None:
return None
axis = 0 if self.axisOrder == 'col-major' else 1
return self.image.shape[axis]
def height(self):
if self.image is None:
return None
axis = 1 if self.axisOrder == 'col-major' else 0
return self.image.shape[axis]
def channels(self):
if self.image is None:
return None
return self.image.shape[2] if self.image.ndim == 3 else 1
def boundingRect(self):
if self.image is None:
return QtCore.QRectF(0., 0., 0., 0.)
return QtCore.QRectF(0., 0., float(self.width()), float(self.height()))
[docs] def setLevels(self, levels, update=True):
"""
Sets image scaling levels.
See :func:`makeARGB <pyqtgraph.makeARGB>` for more details on how levels are applied.
Parameters
----------
levels: list_like
- [`blackLevel`, `whiteLevel`]
sets black and white levels for monochrome data and can be used with a lookup table.
- [[`minR`, `maxR`], [`minG`, `maxG`], [`minB`, `maxB`]]
sets individual scaling for RGB values. Not compatible with lookup tables.
update: bool, optional
Controls if image immediately updates to reflect the new levels.
"""
if self._xp is None:
self.levels = levels
self._defferedLevels = levels
return
if levels is not None:
levels = self._xp.asarray(levels)
self.levels = levels
self._effectiveLut = None
if update:
self.updateImage()
[docs] def getLevels(self):
"""
Returns the list representing the current level settings. See :func:`~setLevels`.
When ``autoLevels`` is active, the format is [`blackLevel`, `whiteLevel`].
"""
return self.levels
[docs] def setLookupTable(self, lut, update=True):
"""
Sets lookup table `lut` to use for false color display of a monochrome image. See :func:`makeARGB <pyqtgraph.makeARGB>` for more
information on how this is used. Optionally, `lut` can be a callable that accepts the current image as an
argument and returns the lookup table to use.
Ordinarily, this table is supplied by a :class:`~pyqtgraph.HistogramLUTItem`,
:class:`~pyqtgraph.GradientEditorItem` or :class:`~pyqtgraph.ColorBarItem`.
Setting `update` to False avoids an immediate image update.
"""
if lut is not self.lut:
if self._xp is not None:
lut = self._ensure_proper_substrate(lut, self._xp)
self.lut = lut
self._effectiveLut = None
if update:
self.updateImage()
@staticmethod
def _ensure_proper_substrate(data, substrate):
if data is None or isinstance(data, Callable) or isinstance(data, substrate.ndarray):
return data
cupy = getCupy()
if substrate == cupy and not isinstance(data, cupy.ndarray):
data = cupy.asarray(data)
elif substrate == numpy:
if cupy is not None and isinstance(data, cupy.ndarray):
data = data.get()
else:
data = numpy.asarray(data)
return data
[docs] def setAutoDownsample(self, active=True):
"""
Controls automatic downsampling for this ImageItem.
If active is `True`, the image is automatically downsampled to match the
screen resolution. This improves performance for large images and
reduces aliasing. If autoDownsample is not specified, then ImageItem will
choose whether to downsample the image based on its size.
`False` disables automatic downsampling.
"""
self.autoDownsample = active
self._renderRequired = True
self.update()
[docs] def setOpts(self, update=True, **kargs):
"""
Sets display and processing options for this ImageItem. :func:`~pyqtgraph.ImageItem.__init__` and
:func:`~pyqtgraph.ImageItem.setImage` support all keyword arguments listed here.
Parameters
----------
autoDownsample: bool
See :func:`~pyqtgraph.ImageItem.setAutoDownsample`.
axisOrder: str
| `'col-major'`: The shape of the array represents (width, height) of the image. This is the default.
| `'row-major'`: The shape of the array represents (height, width).
border: bool
Sets a pen to draw to draw an image border. See :func:`~pyqtgraph.ImageItem.setBorder`.
compositionMode:
See :func:`~pyqtgraph.ImageItem.setCompositionMode`
lut: array
Sets a color lookup table to use when displaying the image.
See :func:`~pyqtgraph.ImageItem.setLookupTable`.
levels: list_like, usally [`min`, `max`]
Sets minimum and maximum values to use when rescaling the image data. By default, these will be set to
the estimated minimum and maximum values in the image. If the image array has dtype uint8, no rescaling
is necessary. See :func:`~pyqtgraph.ImageItem.setLevels`.
opacity: float, 0.0-1.0
Overall opacity for an RGB image.
rect: QRectF, QRect or array_like of floats (`x`,`y`,`w`,`h`)
Displays the current image within the specified rectangle in plot coordinates.
See :func:`~pyqtgraph.ImageItem.setRect`.
update : bool, optional
Controls if image immediately updates to reflect the new options.
"""
if 'axisOrder' in kargs:
val = kargs['axisOrder']
if val not in ('row-major', 'col-major'):
raise ValueError("axisOrder must be either 'row-major' or 'col-major'")
self.axisOrder = val
self._update_data_transforms(self.axisOrder) # update cached transforms
if 'lut' in kargs:
self.setLookupTable(kargs['lut'], update=update)
if 'levels' in kargs:
self.setLevels(kargs['levels'], update=update)
#if 'clipLevel' in kargs:
#self.setClipLevel(kargs['clipLevel'])
if 'opacity' in kargs:
self.setOpacity(kargs['opacity'])
if 'compositionMode' in kargs:
self.setCompositionMode(kargs['compositionMode'])
if 'border' in kargs:
self.setBorder(kargs['border'])
if 'removable' in kargs:
self.removable = kargs['removable']
self.menu = None
if 'autoDownsample' in kargs:
self.setAutoDownsample(kargs['autoDownsample'])
if 'rect' in kargs:
self.setRect(kargs['rect'])
if update:
self.update()
[docs] def setRect(self, *args):
"""
setRect(rect) or setRect(x,y,w,h)
Sets translation and scaling of this ImageItem to display the current image within the rectangle given
as ``QtCore.QRect`` or ``QtCore.QRectF`` `rect`, or described by parameters `x, y, w, h`, defining starting
position, width and height.
This method cannot be used before an image is assigned.
See the :ref:`examples <ImageItem_examples>` for how to manually set transformations.
"""
if len(args) == 0:
self.resetTransform() # reset scaling and rotation when called without argument
return
if isinstance(args[0], (QtCore.QRectF, QtCore.QRect)):
rect = args[0] # use QRectF or QRect directly
else:
if hasattr(args[0],'__len__'):
args = args[0] # promote tuple or list of values
rect = QtCore.QRectF( *args ) # QRectF(x,y,w,h), but also accepts other initializers
tr = QtGui.QTransform()
tr.translate(rect.left(), rect.top())
tr.scale(rect.width() / self.width(), rect.height() / self.height())
self.setTransform(tr)
[docs] def clear(self):
"""
Clears the assigned image.
"""
self.image = None
self.prepareGeometryChange()
self.informViewBoundsChanged()
self.update()
def _buildQImageBuffer(self, shape):
self._displayBuffer = numpy.empty(shape[:2] + (4,), dtype=numpy.ubyte)
if self._xp == getCupy():
self._processingBuffer = self._xp.empty(shape[:2] + (4,), dtype=self._xp.ubyte)
else:
self._processingBuffer = self._displayBuffer
self.qimage = None
[docs] def setImage(self, image=None, autoLevels=None, **kargs):
"""
Updates the image displayed by this ImageItem. For more information on how the image
is processed before displaying, see :func:`~pyqtgraph.makeARGB>`.
For backward compatibility, image data is assumed to be in column-major order (column, row) by default.
However, most data is stored in row-major order (row, column). It can either be transposed before assignment::
imageitem.setImage(imagedata.T)
or the interpretation of the data can be changed locally through the ``axisOrder`` keyword or by changing the
`imageAxisOrder` :ref:`global configuration option <apiref_config>`.
All keywords supported by :func:`~pyqtgraph.ImageItem.setOpts` are also allowed here.
Parameters
----------
image: array
Image data given as NumPy array with an integer or floating
point dtype of any bit depth. A 2-dimensional array describes single-valued (monochromatic) data.
A 3-dimensional array is used to give individual color components. The third dimension must
be of length 3 (RGB) or 4 (RGBA).
rect: QRectF, QRect or list_like of floats (`x, y, w, h`), optional
If given, sets translation and scaling to display the image within the specified rectangle. See
:func:`~pyqtgraph.ImageItem.setRect`.
autoLevels: bool, optional
If True, ImageItem will automatically select levels based on the maximum and minimum values encountered
in the data. For performance reasons, this search subsamples the images and may miss individual bright or
or dark points in the data set.
If False, the search will be omitted.
The default is `False` if a ``levels`` keyword argument is given, and `True` otherwise.
levelSamples: int, default 65536
When determining minimum and maximum values, ImageItem
only inspects a subset of pixels no larger than this number.
Setting this larger than the total number of pixels considers all values.
"""
profile = debug.Profiler()
gotNewData = False
if image is None:
if self.image is None:
return
else:
old_xp = self._xp
cp = getCupy()
self._xp = cp.get_array_module(image) if cp else numpy
gotNewData = True
processingSubstrateChanged = old_xp != self._xp
if processingSubstrateChanged:
self._processingBuffer = None
shapeChanged = (processingSubstrateChanged or self.image is None or image.shape != self.image.shape)
image = image.view()
if self.image is None or image.dtype != self.image.dtype:
self._effectiveLut = None
self.image = image
if self.image.shape[0] > 2**15-1 or self.image.shape[1] > 2**15-1:
if 'autoDownsample' not in kargs:
kargs['autoDownsample'] = True
if shapeChanged:
self.prepareGeometryChange()
self.informViewBoundsChanged()
profile()
if autoLevels is None:
if 'levels' in kargs:
autoLevels = False
else:
autoLevels = True
if autoLevels:
level_samples = kargs.pop('levelSamples', 2**16)
mn, mx = self.quickMinMax( targetSize=level_samples )
# mn and mx can still be NaN if the data is all-NaN
if mn == mx or self._xp.isnan(mn) or self._xp.isnan(mx):
mn = 0
mx = 255
kargs['levels'] = [mn,mx]
profile()
self.setOpts(update=False, **kargs)
profile()
self._renderRequired = True
self.update()
profile()
if gotNewData:
self.sigImageChanged.emit()
if self._defferedLevels is not None:
levels = self._defferedLevels
self._defferedLevels = None
self.setLevels((levels))
def _update_data_transforms(self, axisOrder='col-major'):
""" Sets up the transforms needed to map between input array and display """
self._dataTransform = QtGui.QTransform()
self._inverseDataTransform = QtGui.QTransform()
if self.axisOrder == 'row-major': # transpose both
self._dataTransform.scale(1, -1)
self._dataTransform.rotate(-90)
self._inverseDataTransform.scale(1, -1)
self._inverseDataTransform.rotate(-90)
def dataTransform(self):
"""
Returns the transform that maps from this image's input array to its
local coordinate system.
This transform corrects for the transposition that occurs when image data
is interpreted in row-major order.
:meta private:
"""
# Might eventually need to account for downsampling / clipping here
# transforms are updated in setOpts call.
return self._dataTransform
def inverseDataTransform(self):
"""Return the transform that maps from this image's local coordinate
system to its input array.
See dataTransform() for more information.
:meta private:
"""
# transforms are updated in setOpts call.
return self._inverseDataTransform
def mapToData(self, obj):
return self._inverseDataTransform.map(obj)
def mapFromData(self, obj):
return self._dataTransform.map(obj)
[docs] def quickMinMax(self, targetSize=1e6):
"""
Estimates the min/max values of the image data by subsampling.
Subsampling is performed at regular strides chosen to evaluate a number of samples
equal to or less than `targetSize`.
Returns (`min`, `max`).
"""
data = self.image
if targetSize < 2: # keep at least two pixels
targetSize = 2
while True:
h, w = data.shape[:2]
if h * w <= targetSize: break
if h > w:
data = data[::2, ::] # downsample first axis
else:
data = data[::, ::2] # downsample second axis
return self._xp.nanmin(data), self._xp.nanmax(data)
def updateImage(self, *args, **kargs):
## used for re-rendering qimage from self.image.
## can we make any assumptions here that speed things up?
## dtype, range, size are all the same?
defaults = {
'autoLevels': False,
}
defaults.update(kargs)
return self.setImage(*args, **defaults)
def render(self):
# Convert data to QImage for display.
self._unrenderable = True
if self.image is None or self.image.size == 0:
return
# Request a lookup table if this image has only one channel
if self.image.ndim == 2 or self.image.shape[2] == 1:
self.lut = self._ensure_proper_substrate(self.lut, self._xp)
if isinstance(self.lut, Callable):
lut = self._ensure_proper_substrate(self.lut(self.image), self._xp)
else:
lut = self.lut
else:
lut = None
if self.autoDownsample:
xds, yds = self._computeDownsampleFactors()
if xds is None:
return
axes = [1, 0] if self.axisOrder == 'row-major' else [0, 1]
image = fn.downsample(self.image, xds, axis=axes[0])
image = fn.downsample(image, yds, axis=axes[1])
self._lastDownsample = (xds, yds)
# Check if downsampling reduced the image size to zero due to inf values.
if image.size == 0:
return
else:
image = self.image
# Convert single-channel image to 2D array
if image.ndim == 3 and image.shape[-1] == 1:
image = image[..., 0]
# Assume images are in column-major order for backward compatibility
# (most images are in row-major order)
if self.axisOrder == 'col-major':
image = image.swapaxes(0, 1)
levels = self.levels
augmented_alpha = False
if image.dtype.kind == 'f':
image, levels, lut, augmented_alpha = self._try_rescale_float(image, levels, lut)
# if we succeeded, we will have an uint8 image with levels None.
# lut if not None will have <= 256 entries
# if the image data is a small int, then we can combine levels + lut
# into a single lut for better performance
elif image.dtype in (self._xp.ubyte, self._xp.uint16):
image, levels, lut, augmented_alpha = self._try_combine_lut(image, levels, lut)
qimage = self._try_make_qimage(image, levels, lut, augmented_alpha)
if qimage is not None:
self._processingBuffer = None
self._displayBuffer = None
self.qimage = qimage
self._renderRequired = False
self._unrenderable = False
return
if self._processingBuffer is None or self._processingBuffer.shape[:2] != image.shape[:2]:
self._buildQImageBuffer(image.shape)
fn.makeARGB(image, lut=lut, levels=levels, output=self._processingBuffer)
if self._xp == getCupy():
self._processingBuffer.get(out=self._displayBuffer)
self.qimage = fn.ndarray_to_qimage(self._displayBuffer, QtGui.QImage.Format.Format_ARGB32)
self._renderRequired = False
self._unrenderable = False
def _try_rescale_float(self, image, levels, lut):
xp = self._xp
augmented_alpha = False
can_handle = False
while True:
if levels is None or levels.ndim != 1:
# float images always need levels
# can't handle multi-channel levels
break
# awkward, but fastest numpy native nan evaluation
if xp.isnan(image.min()):
# don't handle images with nans
# this should be an uncommon case
break
can_handle = True
break
if not can_handle:
return image, levels, lut, augmented_alpha
# Decide on maximum scaled value
if lut is not None:
scale = lut.shape[0]
num_colors = lut.shape[0]
else:
scale = 255.
num_colors = 256
dtype = xp.min_scalar_type(num_colors-1)
minVal, maxVal = levels
if minVal == maxVal:
maxVal = xp.nextafter(maxVal, 2*maxVal)
rng = maxVal - minVal
rng = 1 if rng == 0 else rng
fn_numba = fn.getNumbaFunctions()
if xp == numpy and image.flags.c_contiguous and dtype == xp.uint16 and fn_numba is not None:
lut, augmented_alpha = self._convert_2dlut_to_1dlut(lut)
image = fn_numba.rescale_and_lookup1d(image, scale/rng, minVal, lut)
if image.dtype == xp.uint32:
image = image[..., xp.newaxis].view(xp.uint8)
return image, None, None, augmented_alpha
else:
image = fn.rescaleData(image, scale/rng, offset=minVal, dtype=dtype, clip=(0, num_colors-1))
levels = None
if image.dtype == xp.uint16 and image.ndim == 2:
image, augmented_alpha = self._apply_lut_for_uint16_mono(image, lut)
lut = None
# image is now of type uint8
return image, levels, lut, augmented_alpha
def _try_combine_lut(self, image, levels, lut):
augmented_alpha = False
xp = self._xp
can_handle = False
while True:
if levels is not None and levels.ndim != 1:
# can't handle multi-channel levels
break
if image.dtype == xp.uint16 and levels is None and \
image.ndim == 3 and image.shape[2] == 3:
# uint16 rgb can't be directly displayed, so make it
# pass through effective lut processing
levels = [0, 65535]
if levels is None and lut is None:
# nothing to combine
break
can_handle = True
break
if not can_handle:
return image, levels, lut, augmented_alpha
# distinguish between lut for levels and colors
levels_lut = None
colors_lut = lut
lut = None
eflsize = 2**(image.itemsize*8)
if levels is None:
info = xp.iinfo(image.dtype)
minlev, maxlev = info.min, info.max
else:
minlev, maxlev = levels
levdiff = maxlev - minlev
levdiff = 1 if levdiff == 0 else levdiff # don't allow division by 0
if colors_lut is None:
if image.dtype == xp.ubyte and image.ndim == 2:
# uint8 mono image
ind = xp.arange(eflsize)
levels_lut = fn.rescaleData(ind, scale=255./levdiff,
offset=minlev, dtype=xp.ubyte)
# image data is not scaled. instead, levels_lut is used
# as (grayscale) Indexed8 ColorTable to get the same effect.
# due to the small size of the input to rescaleData(), we
# do not bother caching the result
return image, None, levels_lut, augmented_alpha
else:
# uint16 mono, uint8 rgb, uint16 rgb
# rescale image data by computation instead of by memory lookup
image = fn.rescaleData(image, scale=255./levdiff,
offset=minlev, dtype=xp.ubyte)
return image, None, colors_lut, augmented_alpha
else:
num_colors = colors_lut.shape[0]
effscale = num_colors / levdiff
lutdtype = xp.min_scalar_type(num_colors - 1)
if image.dtype == xp.ubyte or lutdtype != xp.ubyte:
# combine if either:
# 1) uint8 mono image
# 2) colors_lut has more entries than will fit within 8-bits
if self._effectiveLut is None:
ind = xp.arange(eflsize)
levels_lut = fn.rescaleData(ind, scale=effscale,
offset=minlev, dtype=lutdtype, clip=(0, num_colors-1))
efflut = colors_lut[levels_lut]
levels_lut = None
colors_lut = None
self._effectiveLut = efflut
efflut = self._effectiveLut
# apply the effective lut early for the following types:
if image.dtype == xp.uint16 and image.ndim == 2:
image, augmented_alpha = self._apply_lut_for_uint16_mono(image, efflut)
efflut = None
return image, None, efflut, augmented_alpha
else:
# uint16 image with colors_lut <= 256 entries
# don't combine, we will use QImage ColorTable
image = fn.rescaleData(image, scale=effscale,
offset=minlev, dtype=lutdtype, clip=(0, num_colors-1))
return image, None, colors_lut, augmented_alpha
def _apply_lut_for_uint16_mono(self, image, lut):
# Note: compared to makeARGB(), we have already clipped the data to range
xp = self._xp
augmented_alpha = False
# if lut is 1d, then lut[image] is fastest
# if lut is 2d, then lut.take(image, axis=0) is faster than lut[image]
if not image.flags.c_contiguous:
image = lut.take(image, axis=0)
# if lut had dimensions (N, 1), then our resultant image would
# have dimensions (h, w, 1)
if image.ndim == 3 and image.shape[-1] == 1:
image = image[..., 0]
return image, augmented_alpha
# if we are contiguous, we can take a faster codepath where we
# ensure that the lut is 1d
lut, augmented_alpha = self._convert_2dlut_to_1dlut(lut)
fn_numba = fn.getNumbaFunctions()
if xp == numpy and fn_numba is not None:
image = fn_numba.numba_take(lut, image)
else:
image = lut[image]
if image.dtype == xp.uint32:
image = image[..., xp.newaxis].view(xp.uint8)
return image, augmented_alpha
def _convert_2dlut_to_1dlut(self, lut):
# converts:
# - uint8 (N, 1) to uint8 (N,)
# - uint8 (N, 3) or (N, 4) to uint32 (N,)
# this allows faster lookup as 1d lookup is faster
xp = self._xp
augmented_alpha = False
if lut.ndim == 1:
return lut, augmented_alpha
if lut.shape[1] == 3: # rgb
# convert rgb lut to rgba so that it is 32-bits
lut = xp.column_stack([lut, xp.full(lut.shape[0], 255, dtype=xp.uint8)])
augmented_alpha = True
if lut.shape[1] == 4: # rgba
lut = lut.view(xp.uint32)
lut = lut.ravel()
return lut, augmented_alpha
def _try_make_qimage(self, image, levels, lut, augmented_alpha):
xp = self._xp
ubyte_nolvl = image.dtype == xp.ubyte and levels is None
is_passthru8 = ubyte_nolvl and lut is None
is_indexed8 = ubyte_nolvl and image.ndim == 2 and \
lut is not None and lut.shape[0] <= 256
is_passthru16 = image.dtype == xp.uint16 and levels is None and lut is None
can_grayscale16 = is_passthru16 and image.ndim == 2 and \
hasattr(QtGui.QImage.Format, 'Format_Grayscale16')
is_rgba64 = is_passthru16 and image.ndim == 3 and image.shape[2] == 4
# bypass makeARGB for supported combinations
supported = is_passthru8 or is_indexed8 or can_grayscale16 or is_rgba64
if not supported:
return None
if self._xp == getCupy():
image = image.get()
# worthwhile supporting non-contiguous arrays
image = numpy.ascontiguousarray(image)
fmt = None
ctbl = None
if is_passthru8:
# both levels and lut are None
# these images are suitable for display directly
if image.ndim == 2:
fmt = QtGui.QImage.Format.Format_Grayscale8
elif image.shape[2] == 3:
fmt = QtGui.QImage.Format.Format_RGB888
elif image.shape[2] == 4:
if augmented_alpha:
fmt = QtGui.QImage.Format.Format_RGBX8888
else:
fmt = QtGui.QImage.Format.Format_RGBA8888
elif is_indexed8:
# levels and/or lut --> lut-only
fmt = QtGui.QImage.Format.Format_Indexed8
if lut.ndim == 1 or lut.shape[1] == 1:
ctbl = [QtGui.qRgb(x,x,x) for x in lut.ravel().tolist()]
elif lut.shape[1] == 3:
ctbl = [QtGui.qRgb(*rgb) for rgb in lut.tolist()]
elif lut.shape[1] == 4:
ctbl = [QtGui.qRgba(*rgba) for rgba in lut.tolist()]
elif can_grayscale16:
# single channel uint16
# both levels and lut are None
fmt = QtGui.QImage.Format.Format_Grayscale16
elif is_rgba64:
# uint16 rgba
# both levels and lut are None
fmt = QtGui.QImage.Format.Format_RGBA64 # endian-independent
if fmt is None:
raise ValueError("unsupported image type")
qimage = fn.ndarray_to_qimage(image, fmt)
if ctbl is not None:
qimage.setColorTable(ctbl)
return qimage
def paint(self, p, *args):
profile = debug.Profiler()
if self.image is None:
return
if self._renderRequired:
self.render()
if self._unrenderable:
return
profile('render QImage')
if self.paintMode is not None:
p.setCompositionMode(self.paintMode)
profile('set comp mode')
shape = self.image.shape[:2] if self.axisOrder == 'col-major' else self.image.shape[:2][::-1]
p.drawImage(QtCore.QRectF(0,0,*shape), self.qimage)
profile('p.drawImage')
if self.border is not None:
p.setPen(self.border)
p.drawRect(self.boundingRect())
[docs] def save(self, fileName, *args):
"""
Saves this image to file. Note that this saves the visible image (after scale/color changes), not the
original data.
"""
if self._renderRequired:
self.render()
self.qimage.save(fileName, *args)
[docs] def getHistogram(self, bins='auto', step='auto', perChannel=False, targetImageSize=200,
targetHistogramSize=500, **kwds):
"""
Returns `x` and `y` arrays containing the histogram values for the current image.
For an explanation of the return format, see numpy.histogram().
The `step` argument causes pixels to be skipped when computing the histogram to save time.
If `step` is 'auto', then a step is chosen such that the analyzed data has
dimensions approximating `targetImageSize` for each axis.
The `bins` argument and any extra keyword arguments are passed to
``self.xp.histogram()``. If `bins` is `auto`, a bin number is automatically
chosen based on the image characteristics:
* Integer images will have approximately `targetHistogramSize` bins,
with each bin having an integer width.
* All other types will have `targetHistogramSize` bins.
If `perChannel` is `True`, then a histogram is computed for each channel,
and the output is a list of the results.
"""
# This method is also used when automatically computing levels.
if self.image is None or self.image.size == 0:
return None, None
if step == 'auto':
step = (max(1, int(self._xp.ceil(self.image.shape[0] / targetImageSize))),
max(1, int(self._xp.ceil(self.image.shape[1] / targetImageSize))))
if self._xp.isscalar(step):
step = (step, step)
stepData = self.image[::step[0], ::step[1]]
if isinstance(bins, str) and bins == 'auto':
mn = self._xp.nanmin(stepData).item()
mx = self._xp.nanmax(stepData).item()
if mx == mn:
# degenerate image, arange will fail
mx += 1
if self._xp.isnan(mn) or self._xp.isnan(mx):
# the data are all-nan
return None, None
if stepData.dtype.kind in "ui":
# For integer data, we select the bins carefully to avoid aliasing
step = int(self._xp.ceil((mx - mn) / 500.))
bins = []
if step > 0.0:
bins = self._xp.arange(mn, mx + 1.01 * step, step, dtype=int)
else:
# for float data, let numpy select the bins.
bins = self._xp.linspace(mn, mx, 500)
if len(bins) == 0:
bins = self._xp.asarray((mn, mx))
kwds['bins'] = bins
cp = getCupy()
if perChannel:
hist = []
for i in range(stepData.shape[-1]):
stepChan = stepData[..., i]
stepChan = stepChan[self._xp.isfinite(stepChan)]
h = self._xp.histogram(stepChan, **kwds)
if cp:
hist.append((cp.asnumpy(h[1][:-1]), cp.asnumpy(h[0])))
else:
hist.append((h[1][:-1], h[0]))
return hist
else:
stepData = stepData[self._xp.isfinite(stepData)]
hist = self._xp.histogram(stepData, **kwds)
if cp:
return cp.asnumpy(hist[1][:-1]), cp.asnumpy(hist[0])
else:
return hist[1][:-1], hist[0]
[docs] def setPxMode(self, b):
"""
Sets whether the item ignores transformations and draws directly to screen pixels.
If True, the item will not inherit any scale or rotation transformations from its
parent items, but its position will be transformed as usual.
(see ``GraphicsItem::ItemIgnoresTransformations`` in the Qt documentation)
"""
self.setFlag(self.GraphicsItemFlag.ItemIgnoresTransformations, b)
def setScaledMode(self):
self.setPxMode(False)
def getPixmap(self):
if self._renderRequired:
self.render()
if self._unrenderable:
return None
return QtGui.QPixmap.fromImage(self.qimage)
[docs] def pixelSize(self):
"""
Returns the scene-size of a single pixel in the image
"""
br = self.sceneBoundingRect()
if self.image is None:
return 1,1
return br.width()/self.width(), br.height()/self.height()
def viewTransformChanged(self):
if self.autoDownsample:
xds, yds = self._computeDownsampleFactors()
if xds is None:
self._renderRequired = True
self._unrenderable = True
return
if (xds, yds) != self._lastDownsample:
self._renderRequired = True
self.update()
def _computeDownsampleFactors(self):
# reduce dimensions of image based on screen resolution
o = self.mapToDevice(QtCore.QPointF(0, 0))
x = self.mapToDevice(QtCore.QPointF(1, 0))
y = self.mapToDevice(QtCore.QPointF(0, 1))
# scene may not be available yet
if o is None:
return None, None
w = Point(x - o).length()
h = Point(y - o).length()
if w == 0 or h == 0:
return None, None
return max(1, int(1.0 / w)), max(1, int(1.0 / h))
def mouseDragEvent(self, ev):
if ev.button() != QtCore.Qt.MouseButton.LeftButton:
ev.ignore()
return
elif self.drawKernel is not None:
ev.accept()
self.drawAt(ev.pos(), ev)
def mouseClickEvent(self, ev):
if ev.button() == QtCore.Qt.MouseButton.RightButton:
if self.raiseContextMenu(ev):
ev.accept()
if self.drawKernel is not None and ev.button() == QtCore.Qt.MouseButton.LeftButton:
self.drawAt(ev.pos(), ev)
def raiseContextMenu(self, ev):
menu = self.getMenu()
if menu is None:
return False
menu = self.scene().addParentContextMenus(self, menu, ev)
pos = ev.screenPos()
menu.popup(QtCore.QPoint(pos.x(), pos.y()))
return True
def getMenu(self):
if self.menu is None:
if not self.removable:
return None
self.menu = QtGui.QMenu()
self.menu.setTitle(translate("ImageItem", "Image"))
remAct = QtGui.QAction(translate("ImageItem", "Remove image"), self.menu)
remAct.triggered.connect(self.removeClicked)
self.menu.addAction(remAct)
self.menu.remAct = remAct
return self.menu
def hoverEvent(self, ev):
if not ev.isExit() and self.drawKernel is not None and ev.acceptDrags(QtCore.Qt.MouseButton.LeftButton):
ev.acceptClicks(QtCore.Qt.MouseButton.LeftButton) ## we don't use the click, but we also don't want anyone else to use it.
ev.acceptClicks(QtCore.Qt.MouseButton.RightButton)
elif not ev.isExit() and self.removable:
ev.acceptClicks(QtCore.Qt.MouseButton.RightButton) ## accept context menu clicks
def tabletEvent(self, ev):
pass
#print(ev.device())
#print(ev.pointerType())
#print(ev.pressure())
def drawAt(self, pos, ev=None):
pos = [int(pos.x()), int(pos.y())]
dk = self.drawKernel
kc = self.drawKernelCenter
sx = [0,dk.shape[0]]
sy = [0,dk.shape[1]]
tx = [pos[0] - kc[0], pos[0] - kc[0]+ dk.shape[0]]
ty = [pos[1] - kc[1], pos[1] - kc[1]+ dk.shape[1]]
for i in [0,1]:
dx1 = -min(0, tx[i])
dx2 = min(0, self.image.shape[0]-tx[i])
tx[i] += dx1+dx2
sx[i] += dx1+dx2
dy1 = -min(0, ty[i])
dy2 = min(0, self.image.shape[1]-ty[i])
ty[i] += dy1+dy2
sy[i] += dy1+dy2
ts = (slice(tx[0],tx[1]), slice(ty[0],ty[1]))
ss = (slice(sx[0],sx[1]), slice(sy[0],sy[1]))
mask = self.drawMask
src = dk
if isinstance(self.drawMode, Callable):
self.drawMode(dk, self.image, mask, ss, ts, ev)
else:
src = src[ss]
if self.drawMode == 'set':
if mask is not None:
mask = mask[ss]
self.image[ts] = self.image[ts] * (1-mask) + src * mask
else:
self.image[ts] = src
elif self.drawMode == 'add':
self.image[ts] += src
else:
raise Exception("Unknown draw mode '%s'" % self.drawMode)
self.updateImage()
def setDrawKernel(self, kernel=None, mask=None, center=(0,0), mode='set'):
self.drawKernel = kernel
self.drawKernelCenter = center
self.drawMode = mode
self.drawMask = mask
def removeClicked(self):
## Send remove event only after we have exited the menu event handler
self.removeTimer = QtCore.QTimer()
self.removeTimer.timeout.connect(self.emitRemoveRequested)
self.removeTimer.start(0)
def emitRemoveRequested(self):
self.removeTimer.timeout.disconnect(self.emitRemoveRequested)
self.sigRemoveRequested.emit(self)