pyqtgraph/pyqtgraph/graphicsItems/ImageItem.py

968 lines
37 KiB
Python

# -*- 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']
class ImageItem(GraphicsObject):
"""
**Bases:** :class:`GraphicsObject <pyqtgraph.GraphicsObject>`
GraphicsObject displaying an image. Optimized for rapid update (ie video display).
This item displays either a 2D numpy array (height, width) or
a 3D array (height, width, RGBa). This array is optionally scaled (see
:func:`setLevels <pyqtgraph.ImageItem.setLevels>`) and/or colored
with a lookup table (see :func:`setLookupTable <pyqtgraph.ImageItem.setLookupTable>`)
before being displayed.
ImageItem is frequently used in conjunction with
:class:`HistogramLUTItem <pyqtgraph.HistogramLUTItem>` or
:class:`HistogramLUTWidget <pyqtgraph.HistogramLUTWidget>` to provide a GUI
for controlling the levels and lookup table used to display the image.
"""
sigImageChanged = QtCore.Signal()
sigRemoveRequested = QtCore.Signal(object) # self; emitted when 'remove' is selected from context menu
def __init__(self, image=None, **kargs):
"""
See :func:`setImage <pyqtgraph.ImageItem.setImage>` for all allowed initialization arguments.
"""
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')
# 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)
def setCompositionMode(self, mode):
"""Change the composition mode of the item (see QPainter::CompositionMode
in the Qt documentation). This is useful when overlaying multiple ImageItems.
============================================ ============================================================
**Most common arguments:**
QtGui.QPainter.CompositionMode_SourceOver Default; image replaces the background if it
is opaque. Otherwise, it uses the alpha channel to blend
the image with the background.
QtGui.QPainter.CompositionMode_Overlay The image color is mixed with the background color to
reflect the lightness or darkness of the background.
QtGui.QPainter.CompositionMode_Plus Both the alpha and color of the image and background pixels
are added together.
QtGui.QPainter.CompositionMode_Multiply The output is the image color multiplied by the background.
============================================ ============================================================
"""
self.paintMode = mode
self.update()
def setBorder(self, b):
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()))
def setLevels(self, levels, update=True):
"""
Set image scaling levels. Can be one of:
* [blackLevel, whiteLevel]
* [[minRed, maxRed], [minGreen, maxGreen], [minBlue, maxBlue]]
Only the first format is compatible with lookup tables. See :func:`makeARGB <pyqtgraph.makeARGB>`
for more details on how levels are applied.
"""
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()
def getLevels(self):
return self.levels
#return self.whiteLevel, self.blackLevel
def setLookupTable(self, lut, update=True):
"""
Set the lookup table (numpy array) to use for this 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:`HistogramLUTItem <pyqtgraph.HistogramLUTItem>`
or :class:`GradientEditorItem <pyqtgraph.GradientEditorItem>`.
"""
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
def setAutoDownsample(self, ads):
"""
Set the automatic downsampling mode for this ImageItem.
Added in version 0.9.9
"""
self.autoDownsample = ads
self._renderRequired = True
self.update()
def setOpts(self, update=True, **kargs):
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
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 update:
self.update()
def setRect(self, rect):
"""Scale and translate the image to fit within rect (must be a QRect or QRectF)."""
tr = QtGui.QTransform()
tr.translate(rect.left(), rect.top())
tr.scale(rect.width() / self.width(), rect.height() / self.height())
self.setTransform(tr)
def clear(self):
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 = fn.makeQImage(self._displayBuffer, transpose=False, copy=False)
def setImage(self, image=None, autoLevels=None, **kargs):
"""
Update the image displayed by this item. For more information on how the image
is processed before displaying, see :func:`makeARGB <pyqtgraph.makeARGB>`
================= =========================================================================
**Arguments:**
image (numpy array) Specifies the image data. May be 2D (width, height) or
3D (width, height, RGBa). The array dtype must be integer or floating
point of any bit depth. For 3D arrays, the third dimension must
be of length 3 (RGB) or 4 (RGBA). See *notes* below.
autoLevels (bool) If True, this forces the image to automatically select
levels based on the maximum and minimum values in the data.
By default, this argument is true unless the levels argument is
given.
lut (numpy array) The color lookup table to use when displaying the image.
See :func:`setLookupTable <pyqtgraph.ImageItem.setLookupTable>`.
levels (min, max) The minimum and maximum values to use when rescaling the image
data. By default, this will be set to the minimum and maximum values
in the image. If the image array has dtype uint8, no rescaling is necessary.
opacity (float 0.0-1.0)
compositionMode See :func:`setCompositionMode <pyqtgraph.ImageItem.setCompositionMode>`
border Sets the pen used when drawing the image border. Default is None.
autoDownsample (bool) If 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.
================= =========================================================================
**Notes:**
For backward compatibility, image data is assumed to be in column-major order (column, row).
However, most image data is stored in row-major order (row, column) and will need to be
transposed before calling setImage()::
imageitem.setImage(imagedata.T)
This requirement can be changed by calling ``image.setOpts(axisOrder='row-major')`` or
by changing the ``imageAxisOrder`` :ref:`global configuration option <apiref_config>`.
"""
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:
img = self.image
while img.size > 2**16:
img = img[::2, ::2]
mn, mx = self._xp.nanmin(img), self._xp.nanmax(img)
# 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 dataTransform(self):
"""Return 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.
"""
# Might eventually need to account for downsampling / clipping here
tr = QtGui.QTransform()
if self.axisOrder == 'row-major':
# transpose
tr.scale(1, -1)
tr.rotate(-90)
return tr
def inverseDataTransform(self):
"""Return the transform that maps from this image's local coordinate
system to its input array.
See dataTransform() for more information.
"""
tr = QtGui.QTransform()
if self.axisOrder == 'row-major':
# transpose
tr.scale(1, -1)
tr.rotate(-90)
return tr
def mapToData(self, obj):
tr = self.inverseDataTransform()
return tr.map(obj)
def mapFromData(self, obj):
tr = self.dataTransform()
return tr.map(obj)
def quickMinMax(self, targetSize=1e6):
"""
Estimate the min/max values of the image data by subsampling.
"""
data = self.image
while data.size > targetSize:
ax = self._xp.argmax(data.shape)
sl = [slice(None)] * data.ndim
sl[ax] = slice(None, None, 2)
data = data[sl]
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.lut(self.image)
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._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
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
if lut.ndim == 2:
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)
image = lut.ravel()[image]
lut = None
# now both levels and lut are None
if image.dtype == xp.uint32:
image = image.view(xp.uint8).reshape(image.shape + (4,))
return image, 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())
def save(self, fileName, *args):
"""Save 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)
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 roughly *targetImageSize* for each axis.
The *bins* argument and any extra keyword arguments are passed to
self.xp.histogram(). If *bins* is 'auto', then 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 the histogram is computed once per 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=self._xp.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]
def setPxMode(self, b):
"""
Set 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.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)
def pixelSize(self):
"""return 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.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.RightButton:
if self.raiseContextMenu(ev):
ev.accept()
if self.drawKernel is not None and ev.button() == QtCore.Qt.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.LeftButton):
ev.acceptClicks(QtCore.Qt.LeftButton) ## we don't use the click, but we also don't want anyone else to use it.
ev.acceptClicks(QtCore.Qt.RightButton)
elif not ev.isExit() and self.removable:
ev.acceptClicks(QtCore.Qt.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)