Source code for pydm.widgets.image

from qtpy.QtWidgets import QActionGroup
from qtpy.QtCore import Signal, Slot, Property, QTimer, Q_ENUMS, QThread
from pyqtgraph import ImageView, PlotItem
from pyqtgraph import ColorMap
from pyqtgraph.graphicsItems.ViewBox.ViewBoxMenu import ViewBoxMenu
import numpy as np
import logging
from .channel import PyDMChannel
from .colormaps import cmaps, cmap_names, PyDMColorMap
from .base import PyDMWidget

logger = logging.getLogger(__name__)

class ReadingOrder(object):
    """Class to build ReadingOrder ENUM property."""

    Fortranlike = 0
    Clike = 1

class ImageUpdateThread(QThread):
    updateSignal = Signal(list)

    def __init__(self, image_view):
        self.image_view = image_view

    def run(self):
        img = self.image_view.image_waveform
        needs_redraw = self.image_view.needs_redraw
        image_dimensions = len(img.shape)
        width = self.image_view.imageWidth
        reading_order = self.image_view.readingOrder
        normalize_data = self.image_view._normalize_data
        cm_min = self.image_view.cm_min
        cm_max = self.image_view.cm_max

        if not needs_redraw:
            logging.debug("ImageUpdateThread - needs redraw is False. Aborting.")
        if image_dimensions == 1:
            if width < 1:
                # We don't have a width for this image yet, so we can't draw it
                logging.debug("ImageUpdateThread - no width available. Aborting.")
                if reading_order == ReadingOrder.Clike:
                    img = img.reshape((-1, width), order="C")
                    img = img.reshape((width, -1), order="F")
            except ValueError:
                logger.error("Invalid width for image during reshape: %d", width)

        if len(img) <= 0:
        logging.debug("ImageUpdateThread - Will Process Image")
        img = self.image_view.process_image(img)
        if normalize_data:
            mini = img.min()
            maxi = img.max()
            mini = cm_min
            maxi = cm_max
        logging.debug("ImageUpdateThread - Emit Update Signal")
        self.updateSignal.emit([mini, maxi, img])
        logging.debug("ImageUpdateThread - Set Needs Redraw -> False")
        self.image_view.needs_redraw = False

[docs]class PyDMImageView(ImageView, PyDMWidget, PyDMColorMap, ReadingOrder): """ A PyQtGraph ImageView with support for Channels and more from PyDM. If there is no :attr:`channelWidth` it is possible to define the width of the image with the :attr:`width` property. The :attr:`normalizeData` property defines if the colors of the images are relative to the :attr:`colorMapMin` and :attr:`colorMapMax` property or to the minimum and maximum values of the image. Use the :attr:`newImageSignal` to hook up to a signal that is emitted when a new image is rendered in the widget. Parameters ---------- parent : QWidget The parent widget for the Label image_channel : str, optional The channel to be used by the widget for the image data. width_channel : str, optional The channel to be used by the widget to receive the image width information """ ReadingOrder = ReadingOrder Q_ENUMS(ReadingOrder) Q_ENUMS(PyDMColorMap) color_maps = cmaps def __init__(self, parent=None, image_channel=None, width_channel=None): """Initialize widget.""" # Set the default colormap. self._colormap = PyDMColorMap.Inferno self._cm_colors = None self._imagechannel = None self._widthchannel = None self.image_waveform = np.zeros(0) self._image_width = 0 self._normalize_data = False self._auto_downsample = True self._show_axes = False # Set default reading order of numpy array data to Fortranlike. self._reading_order = ReadingOrder.Fortranlike self._redraw_rate = 30 # Set color map limits. self.cm_min = 0.0 self.cm_max = 255.0 plot_item = PlotItem() ImageView.__init__(self, parent, view=plot_item) PyDMWidget.__init__(self) self._channels = [None, None] self.thread = None self.axes = dict({"t": None, "x": 0, "y": 1, "c": None}) self.showAxes = self._show_axes self.imageItem.setOpts(axisOrder="row-major") # Hide some itens of the widget. self.ui.histogram.hide() self.getImageItem().sigImageChanged.disconnect(self.ui.histogram.imageChanged) self.ui.roiBtn.hide() self.ui.menuBtn.hide() # Make a right-click menu for changing the color map. self.cm_group = QActionGroup(self) self.cmap_for_action = {} for cm in self.color_maps: action = self.cm_group.addAction(cmap_names[cm]) action.setCheckable(True) self.cmap_for_action[action] = cm self.colorMap = self._colormap # Setup the redraw timer. self.needs_redraw = False self.redraw_timer = QTimer(self) self.redraw_timer.timeout.connect(self.redrawImage) self.maxRedrawRate = self._redraw_rate self.newImageSignal = self.getImageItem().sigImageChanged # Set live channels if requested on initialization if image_channel: self.imageChannel = image_channel or "" if width_channel: self.widthChannel = width_channel or "" @Property(str, designable=False) def channel(self): return @channel.setter def channel(self, ch): if not ch: return"Use the imageChannel property with the ImageView widget.") return
[docs] def widget_ctx_menu(self): """ Fetch the Widget specific context menu. It will be populated with additional tools by `assemble_tools_menu`. Returns ------- QMenu or None If the return of this method is None a new QMenu will be created by `assemble_tools_menu`. """ = ViewBoxMenu(self.getView().getViewBox()) cm_menu ="Color Map") for act in self.cmap_for_action.keys(): cm_menu.addAction(act) cm_menu.triggered.connect(self._changeColorMap) return
def _changeColorMap(self, action): """ Method invoked by the colormap Action Menu. Changes the current colormap used to render the image. Parameters ---------- action : QAction """ self.colorMap = self.cmap_for_action[action] @Property(float) def colorMapMin(self): """ Minimum value for the colormap. Returns ------- float """ return self.cm_min @colorMapMin.setter @Slot(float) def colorMapMin(self, new_min): """ Set the minimum value for the colormap. Parameters ---------- new_min : float """ if self.cm_min != new_min: self.cm_min = new_min if self.cm_min > self.cm_max: self.cm_max = self.cm_min @Property(float) def colorMapMax(self): """ Maximum value for the colormap. Returns ------- float """ return self.cm_max @colorMapMax.setter @Slot(float) def colorMapMax(self, new_max): """ Set the maximum value for the colormap. Parameters ---------- new_max : float """ if self.cm_max != new_max: self.cm_max = new_max if self.cm_max < self.cm_min: self.cm_min = self.cm_max
[docs] def setColorMapLimits(self, mn, mx): """ Set the limit values for the colormap. Parameters ---------- mn : int The lower limit mx : int The upper limit """ if mn >= mx: return self.cm_max = mx self.cm_min = mn
@Property(PyDMColorMap) def colorMap(self): """ Return the color map used by the ImageView. Returns ------- PyDMColorMap """ return self._colormap @colorMap.setter def colorMap(self, new_cmap): """ Set the color map used by the ImageView. Parameters ------- new_cmap : PyDMColorMap """ self._colormap = new_cmap self._cm_colors = self.color_maps[new_cmap] self.setColorMap() for action in self.cm_group.actions(): if self.cmap_for_action[action] == self._colormap: action.setChecked(True) else: action.setChecked(False)
[docs] def setColorMap(self, cmap=None): """ Update the image colormap. Parameters ---------- cmap : ColorMap """ if not cmap: if not self._cm_colors.any(): return # Take default values pos = np.linspace(0.0, 1.0, num=len(self._cm_colors)) cmap = ColorMap(pos, self._cm_colors) self.getView().getViewBox().setBackgroundColor( lut = cmap.getLookupTable(0.0, 1.0, alpha=False) self.getImageItem().setLookupTable(lut)
[docs] @Slot(bool) def image_connection_state_changed(self, conn): """ Callback invoked when the Image Channel connection state is changed. Parameters ---------- conn : bool The new connection state. """ if conn: self.redraw_timer.start() else: self.redraw_timer.stop()
[docs] @Slot(np.ndarray) def image_value_changed(self, new_image): """ Callback invoked when the Image Channel value is changed. We try to do as little as possible in this method, because it gets called every time the image channel updates, which might be extremely often. Basically just store the data, and set a flag requesting that the image be redrawn. Parameters ---------- new_image : np.ndarray The new image data. This can be a flat 1D array, or a 2D array. """ if new_image is None or new_image.size == 0: return logging.debug("ImageView Received New Image - Needs Redraw -> True") self.image_waveform = new_image self.needs_redraw = True
[docs] @Slot(int) def image_width_changed(self, new_width): """ Callback invoked when the Image Width Channel value is changed. Parameters ---------- new_width : int The new image width """ if new_width is None: return self._image_width = int(new_width)
[docs] def process_image(self, image): """ Boilerplate method to be used by applications in order to add calculations and also modify the image before it is displayed at the widget. .. warning:: This code runs in a separated QThread so it **MUST** not try to write to QWidgets. Parameters ---------- image : np.ndarray The Image Data as a 2D numpy array Returns ------- np.ndarray The Image Data as a 2D numpy array after processing. """ return image
[docs] def redrawImage(self): """ Set the image data into the ImageItem, if needed. If necessary, reshape the image to 2D first. """ if self.thread is not None and not self.thread.isFinished(): logger.warning("Image processing has taken longer than the refresh rate.") return self.thread = ImageUpdateThread(self) self.thread.updateSignal.connect(self.__updateDisplay) logging.debug("ImageView RedrawImage Thread Launched") self.thread.start()
[docs] def toggleRedraw(self) -> bool: """ Start or stop the thread responsible for drawing the image. Can be called by the user to pause redrawing the image, and resume later if needed. Returns ------- bool True if the image is being redrawn on a timer, false otherwise """ self.redraw_timer.stop() if self.redraw_timer.isActive() else self.redraw_timer.start() return self.redraw_timer.isActive()
@Slot(list) def __updateDisplay(self, data): logging.debug("ImageView Update Display with new image") mini, maxi = data[0], data[1] img = data[2] self.getImageItem().setLevels([mini, maxi]) self.getImageItem().setImage(img, autoLevels=False, autoDownsample=self.autoDownsample) @Property(bool) def autoDownsample(self): """ Return if we should or not apply the autoDownsample option to PyQtGraph. Return ------ bool """ return self._auto_downsample @autoDownsample.setter def autoDownsample(self, new_value): """ Whether we should or not apply the autoDownsample option to PyQtGraph. Parameters ---------- new_value: bool """ if new_value != self._auto_downsample: self._auto_downsample = new_value @Property(int) def imageWidth(self): """ Return the width of the image. Return ------ int """ return self._image_width @imageWidth.setter def imageWidth(self, new_width): """ Set the width of the image. Can be overridden by :attr:`widthChannel`. Parameters ---------- new_width: int """ if self._image_width != int(new_width) and (self._widthchannel is None or self._widthchannel == ""): self._image_width = int(new_width) @Property(bool) def normalizeData(self): """ Return True if the colors are relative to data maximum and minimum. Returns ------- bool """ return self._normalize_data @normalizeData.setter @Slot(bool) def normalizeData(self, new_norm): """ Define if the colors are relative to minimum and maximum of the data. Parameters ---------- new_norm: bool """ if self._normalize_data != new_norm: self._normalize_data = new_norm @Property(ReadingOrder) def readingOrder(self): """ Return the reading order of the :attr:`imageChannel` array. Returns ------- ReadingOrder """ return self._reading_order @readingOrder.setter def readingOrder(self, new_order): """ Set reading order of the :attr:`imageChannel` array. Parameters ---------- new_order: ReadingOrder """ if self._reading_order != new_order: self._reading_order = new_order
[docs] def keyPressEvent(self, ev): """Handle keypress events.""" return
@Property(str) def imageChannel(self): """ The channel address in use for the image data . Returns ------- str Channel address """ if self._imagechannel: return str(self._imagechannel.address) else: return "" @imageChannel.setter def imageChannel(self, value): """ The channel address in use for the image data . Parameters ---------- value : str Channel address """ if self._imagechannel != value: # Disconnect old channel if self._imagechannel: self._imagechannel.disconnect() # Create and connect new channel self._imagechannel = PyDMChannel( address=value, connection_slot=self.image_connection_state_changed, value_slot=self.image_value_changed, severity_slot=self.alarmSeverityChanged, ) self._channels[0] = self._imagechannel self._imagechannel.connect() @Property(str) def widthChannel(self): """ The channel address in use for the image width . Returns ------- str Channel address """ if self._widthchannel: return str(self._widthchannel.address) else: return "" @widthChannel.setter def widthChannel(self, value): """ The channel address in use for the image width . Parameters ---------- value : str Channel address """ if self._widthchannel != value: # Disconnect old channel if self._widthchannel: self._widthchannel.disconnect() # Create and connect new channel self._widthchannel = PyDMChannel( address=value, connection_slot=self.connectionStateChanged, value_slot=self.image_width_changed, severity_slot=self.alarmSeverityChanged, ) self._channels[1] = self._widthchannel self._widthchannel.connect()
[docs] def channels(self): """ Return the channels being used for this Widget. Returns ------- channels : list List of PyDMChannel objects """ return self._channels
[docs] def channels_for_tools(self): """Return channels for tools.""" return [self._imagechannel]
@Property(int) def maxRedrawRate(self): """ The maximum rate (in Hz) at which the plot will be redrawn. The plot will not be redrawn if there is not new data to draw. Returns ------- int """ return self._redraw_rate @maxRedrawRate.setter def maxRedrawRate(self, redraw_rate): """ The maximum rate (in Hz) at which the plot will be redrawn. The plot will not be redrawn if there is not new data to draw. Parameters ------- redraw_rate : int """ self._redraw_rate = redraw_rate self.redraw_timer.setInterval(int((1.0 / self._redraw_rate) * 1000)) @Property(bool) def showAxes(self): """ Whether or not axes should be shown on the widget. """ return self._show_axes @showAxes.setter def showAxes(self, show): self._show_axes = show self.getView().showAxis("left", show=show) self.getView().showAxis("bottom", show=show) @Property(float) def scaleXAxis(self): """ Sets the scale for the X Axis. For example, if your image has 100 pixels per millimeter, you can set xAxisScale to 1/100 = 0.01 to make the X Axis report in millimeter units. """ # protect against access to not yet initialized view if hasattr(self, "view"): return self.getView().getAxis("bottom").scale return None @scaleXAxis.setter def scaleXAxis(self, new_scale): self.getView().getAxis("bottom").setScale(new_scale) @Property(float) def scaleYAxis(self): """ Sets the scale for the Y Axis. For example, if your image has 100 pixels per millimeter, you can set yAxisScale to 1/100 = 0.01 to make the Y Axis report in millimeter units. """ # protect against access to not yet initialized view if hasattr(self, "view"): return self.getView().getAxis("left").scale return None @scaleYAxis.setter def scaleYAxis(self, new_scale): self.getView().getAxis("left").setScale(new_scale)