win11 labelme 汉化菜单

替换 app.py,再重启

#labelme 汉化菜单

# -*- coding: utf-8 -*-

import functools
import os
import os.path as osp
import re
import webbrowser

import imgviz
from qtpy import QtCore
from qtpy.QtCore import Qt
from qtpy import QtGui
from qtpy import QtWidgets

from labelme import __appname__
from labelme import PY2
from labelme import QT5

from . import utils
from labelme.config import get_config
from labelme.label_file import LabelFile
from labelme.label_file import LabelFileError
from labelme.logger import logger
from labelme.shape import Shape
from labelme.widgets import BrightnessContrastDialog
from labelme.widgets import Canvas
from labelme.widgets import LabelDialog
from labelme.widgets import LabelListWidget
from labelme.widgets import LabelListWidgetItem
from labelme.widgets import ToolBar
from labelme.widgets import UniqueLabelQListWidget
from labelme.widgets import ZoomWidget


# FIXME
# - [medium] Set max zoom value to something big enough for FitWidth/Window

# TODO(unknown):
# - [high] Add polygon movement with arrow keys
# - [high] Deselect shape when clicking and already selected(?)
# - [low,maybe] Preview images on file dialogs.
# - Zoom is too "steppy".


LABEL_COLORMAP = imgviz.label_colormap(value=200)


class MainWindow(QtWidgets.QMainWindow):

    FIT_WINDOW, FIT_WIDTH, MANUAL_ZOOM = 0, 1, 2

    def __init__(
        self,
        config=None,
        filename=None,
        output=None,
        output_file=None,
        output_dir=None,
    ):
        if output is not None:
            logger.warning(
                "argument output is deprecated, use output_file instead"
            )
            if output_file is None:
                output_file = output

        # see labelme/config/default_config.yaml for valid configuration
        if config is None:
            config = get_config()
        self._config = config

        # set default shape colors
        Shape.line_color = QtGui.QColor(*self._config["shape"]["line_color"])
        Shape.fill_color = QtGui.QColor(*self._config["shape"]["fill_color"])
        Shape.select_line_color = QtGui.QColor(
            *self._config["shape"]["select_line_color"]
        )
        Shape.select_fill_color = QtGui.QColor(
            *self._config["shape"]["select_fill_color"]
        )
        Shape.vertex_fill_color = QtGui.QColor(
            *self._config["shape"]["vertex_fill_color"]
        )
        Shape.hvertex_fill_color = QtGui.QColor(
            *self._config["shape"]["hvertex_fill_color"]
        )

        super(MainWindow, self).__init__()
        self.setWindowTitle(__appname__)

        # Whether we need to save or not.
        self.dirty = False

        self._noSelectionSlot = False

        # Main widgets and related state.
        self.labelDialog = LabelDialog(
            parent=self,
            labels=self._config["labels"],
            sort_labels=self._config["sort_labels"],
            show_text_field=self._config["show_label_text_field"],
            completion=self._config["label_completion"],
            fit_to_content=self._config["fit_to_content"],
            flags=self._config["label_flags"],
        )

        self.labelList = LabelListWidget()
        self.lastOpenDir = None

        self.flag_dock = self.flag_widget = None
        self.flag_dock = QtWidgets.QDockWidget(self.tr("标记"), self)
        self.flag_dock.setObjectName("Flags")
        self.flag_widget = QtWidgets.QListWidget()
        if config["flags"]:
            self.loadFlags({k: False for k in config["flags"]})
        self.flag_dock.setWidget(self.flag_widget)
        self.flag_widget.itemChanged.connect(self.setDirty)

        self.labelList.itemSelectionChanged.connect(self.labelSelectionChanged)
        self.labelList.itemDoubleClicked.connect(self.editLabel)
        self.labelList.itemChanged.connect(self.labelItemChanged)
        self.labelList.itemDropped.connect(self.labelOrderChanged)
        self.shape_dock = QtWidgets.QDockWidget(
            self.tr("多边形标注"), self
        )
        self.shape_dock.setObjectName("Labels")
        self.shape_dock.setWidget(self.labelList)

        self.uniqLabelList = UniqueLabelQListWidget()
        self.uniqLabelList.setToolTip(
            self.tr(
                "选择标签开始标注. "
                "按'Esc'取消选择."
            )
        )
        if self._config["labels"]:
            for label in self._config["labels"]:
                item = self.uniqLabelList.createItemFromLabel(label)
                self.uniqLabelList.addItem(item)
                rgb = self._get_rgb_by_label(label)
                self.uniqLabelList.setItemLabel(item, label, rgb)
        self.label_dock = QtWidgets.QDockWidget(self.tr(u"标签列表"), self)
        self.label_dock.setObjectName(u"Label List")
        self.label_dock.setWidget(self.uniqLabelList)

        self.fileSearch = QtWidgets.QLineEdit()
        self.fileSearch.setPlaceholderText(self.tr("搜索文件名"))
        self.fileSearch.textChanged.connect(self.fileSearchChanged)
        self.fileListWidget = QtWidgets.QListWidget()
        self.fileListWidget.itemSelectionChanged.connect(
            self.fileSelectionChanged
        )
        fileListLayout = QtWidgets.QVBoxLayout()
        fileListLayout.setContentsMargins(0, 0, 0, 0)
        fileListLayout.setSpacing(0)
        fileListLayout.addWidget(self.fileSearch)
        fileListLayout.addWidget(self.fileListWidget)
        self.file_dock = QtWidgets.QDockWidget(self.tr(u"文件列表"), self)
        self.file_dock.setObjectName(u"Files")
        fileListWidget = QtWidgets.QWidget()
        fileListWidget.setLayout(fileListLayout)
        self.file_dock.setWidget(fileListWidget)

        self.zoomWidget = ZoomWidget()
        self.setAcceptDrops(True)

        self.canvas = self.labelList.canvas = Canvas(
            epsilon=self._config["epsilon"],
            double_click=self._config["canvas"]["double_click"],
        )
        self.canvas.zoomRequest.connect(self.zoomRequest)

        scrollArea = QtWidgets.QScrollArea()
        scrollArea.setWidget(self.canvas)
        scrollArea.setWidgetResizable(True)
        self.scrollBars = {
            Qt.Vertical: scrollArea.verticalScrollBar(),
            Qt.Horizontal: scrollArea.horizontalScrollBar(),
        }
        self.canvas.scrollRequest.connect(self.scrollRequest)

        self.canvas.newShape.connect(self.newShape)
        self.canvas.shapeMoved.connect(self.setDirty)
        self.canvas.selectionChanged.connect(self.shapeSelectionChanged)
        self.canvas.drawingPolygon.connect(self.toggleDrawingSensitive)

        self.setCentralWidget(scrollArea)

        features = QtWidgets.QDockWidget.DockWidgetFeatures()
        for dock in ["flag_dock", "label_dock", "shape_dock", "file_dock"]:
            if self._config[dock]["closable"]:
                features = features | QtWidgets.QDockWidget.DockWidgetClosable
            if self._config[dock]["floatable"]:
                features = features | QtWidgets.QDockWidget.DockWidgetFloatable
            if self._config[dock]["movable"]:
                features = features | QtWidgets.QDockWidget.DockWidgetMovable
            getattr(self, dock).setFeatures(features)
            if self._config[dock]["show"] is False:
                getattr(self, dock).setVisible(False)

        self.addDockWidget(Qt.RightDockWidgetArea, self.flag_dock)
        self.addDockWidget(Qt.RightDockWidgetArea, self.label_dock)
        self.addDockWidget(Qt.RightDockWidgetArea, self.shape_dock)
        self.addDockWidget(Qt.RightDockWidgetArea, self.file_dock)

        # Actions
        action = functools.partial(utils.newAction, self)
        shortcuts = self._config["shortcuts"]
        # 修改动作文本
        quit = action(
            self.tr("退出(&Q)"),
            self.close,
            shortcuts["quit"],
            "quit", 
            self.tr("退出程序"),
        )

        open_ = action(
            self.tr("打开(&O)"),
            self.openFile,
            shortcuts["open"],
            "open",
            self.tr("打开图片或标注文件"),
        )

        opendir = action(
            self.tr("打开目录(&D)"),
            self.openDirDialog,
            shortcuts["open_dir"],
            "open",
            self.tr("打开目录"),
        )
        openNextImg = action(
            self.tr("下一张(&N)"),
            self.openNextImg,
            shortcuts["open_next"],
            "next",
            self.tr("打开下一张(按住Ctrl+Shift复制标注)"),
            enabled=False,
        )

        openPrevImg = action(
            self.tr("上一张(&P)"),
            self.openPrevImg, 
            shortcuts["open_prev"],
            "prev",
            self.tr("打开上一张(按住Ctrl+Shift复制标注)"),
            enabled=False,
        )

        save = action(
            self.tr("保存(&S)"),
            self.saveFile,
            shortcuts["save"],
            "save",
            self.tr("保存标注到文件"),
            enabled=False,
        )

        saveAs = action(
            self.tr("另存为(&A)"),
            self.saveFileAs,
            shortcuts["save_as"],
            "save-as", 
            self.tr("保存标注到其他文件"),
            enabled=False,
        )

        deleteFile = action(
            self.tr("删除文件(&D)"),
            self.deleteFile,
            shortcuts["delete_file"],
            "delete",
            self.tr("删除当前标注文件"),
            enabled=False,
        )

        changeOutputDir = action(
            self.tr("更改输出目录(&C)"),
            slot=self.changeOutputDirDialog,
            shortcut=shortcuts["save_to"],
            icon="open",
            tip=self.tr("更改标注文件的加载/保存位置"),
        )

        saveAuto = action(
            text=self.tr("自动保存(&A)"),
            slot=lambda x: self.actions.saveAuto.setChecked(x),
            icon="save",
            tip=self.tr("自动保存"),
            checkable=True,
            enabled=True,
        )
        saveAuto.setChecked(self._config["auto_save"])

        # 9. 按钮文本
        saveWithImageData = action(
            text="Save With Image Data",  # 需要汉化: "保存图像数据"
            slot=self.enableSaveImageWithData,
            tip="Save image data in label file",  # 需要汉化: "在标签文件中保存图像数据"
            checkable=True,
            checked=self._config["store_data"],
        )

        close = action(
            "关闭(&C)",  # 需要汉化: "关闭(&C)"
            self.closeFile,
            shortcuts["close"],
            "close",
            "关闭当前文件",  # 需要汉化: "关闭当前文件"
        )

        toggle_keep_prev_mode = action(
            self.tr("保持上一个标注"),
            self.toggleKeepPrevMode,
            shortcuts["toggle_keep_prev_mode"],
            None,
            self.tr('保持上一个标注"模式'),
            checkable=True,
        )
        toggle_keep_prev_mode.setChecked(self._config["keep_prev"])

        # 10. 其他操作按钮文本
        createMode = action(
            self.tr("创建多边形"),  # 需要汉化: "创建多边形"
            lambda: self.toggleDrawMode(False, createMode="polygon"),
            shortcuts["create_polygon"],
            "objects",
            self.tr("开始绘制多边形"),  # 需要汉化: "开始绘制多边形"
            enabled=False,
        )
        createRectangleMode = action(
            self.tr("创建矩形"),
            lambda: self.toggleDrawMode(False, createMode="rectangle"),
            shortcuts["create_rectangle"],
            "objects",
            self.tr("开始绘制矩形"),
            enabled=False,
        )

        createCircleMode = action(
            self.tr("创建圆形"),
            lambda: self.toggleDrawMode(False, createMode="circle"),
            shortcuts["create_circle"],
            "objects",
            self.tr("开始绘制圆形"),
            enabled=False,
        )

        createLineMode = action(
            self.tr("创建直线"),
            lambda: self.toggleDrawMode(False, createMode="line"),
            shortcuts["create_line"],
            "objects",
            self.tr("开始绘制直线"),
            enabled=False,
        )

        createPointMode = action(
            self.tr("创建点"),
            lambda: self.toggleDrawMode(False, createMode="point"),
            shortcuts["create_point"],
            "objects",
            self.tr("开始绘制点"),
            enabled=False,
        )

        createLineStripMode = action(
            self.tr("创建折线"),
            lambda: self.toggleDrawMode(False, createMode="linestrip"),
            shortcuts["create_linestrip"],
            "objects",
            self.tr("开始绘制折线。按住Ctrl+左键结束创建"),
            enabled=False,
        )

        editMode = action(
            self.tr("编辑多边形"),
            self.setEditMode,
            shortcuts["edit_polygon"],
            "edit",
            self.tr("移动和编辑选中的多边形"),
            enabled=False,
        )

        delete = action(
            self.tr("删除多边形"),
            self.deleteSelectedShape,
            shortcuts["delete_polygon"],
            "cancel",
            self.tr("删除选中的多边形"),
            enabled=False,
        )

        copy = action(
            self.tr("复制多边形"),
            self.copySelectedShape,
            shortcuts["duplicate_polygon"],
            "copy",
            self.tr("创建选中多边形的副本"),
            enabled=False,
        )

        undoLastPoint = action(
            self.tr("撤销上一个点"),
            self.canvas.undoLastPoint,
            shortcuts["undo_last_point"],
            "undo",
            self.tr("撤销上一个绘制的点"),
            enabled=False,
        )

        addPointToEdge = action(
            text=self.tr("添加边缘点"),
            slot=self.canvas.addPointToEdge,
            shortcut=shortcuts["add_point_to_edge"],
            icon="edit",
            tip=self.tr("在最近的边缘添加点"),
            enabled=False,
        )

        removePoint = action(
            text=self.tr("删除选中点"),
            slot=self.canvas.removeSelectedPoint,
            icon="edit",
            tip=self.tr("从多边形中删除选中的点"),
            enabled=False,
        )

        undo = action(
            self.tr("撤销"),
            self.undoShapeEdit,
            shortcuts["undo"],
            "undo",
            self.tr("撤销上一次添加和编辑形状"),
            enabled=False,
        )

        hideAll = action(
            self.tr("隐藏\n多边形"),
            functools.partial(self.togglePolygons, False),
            icon="eye",
            tip=self.tr("隐藏所有多边形"),
            enabled=False,
        )

        showAll = action(
            self.tr("显示\n多边形"),
            functools.partial(self.togglePolygons, True),
            icon="eye",
            tip=self.tr("显示所有多边形"),
            enabled=False,
        )

        help = action(
            self.tr("教程(&T)"),
            self.tutorial,
            icon="help",
            tip=self.tr("显示教程页面"),
        )

        zoom = QtWidgets.QWidgetAction(self)
        zoom.setDefaultWidget(self.zoomWidget)
        self.zoomWidget.setWhatsThis(
            self.tr(
                "放大或缩小图像。也可以使用 "
                "画布上的 {} 和 {} 进行缩放。"
            ).format(
                utils.fmtShortcut(
                    "{},{}".format(shortcuts["zoom_in"], shortcuts["zoom_out"])
                ),
                utils.fmtShortcut(self.tr("Ctrl+滚轮")),
            )
        )
        self.zoomWidget.setEnabled(False)

        zoomIn = action(
            self.tr("放大"),  # 需要汉化: "放大"
            functools.partial(self.addZoom, 1.1),
            shortcuts["zoom_in"],
            "zoom-in",
            self.tr("增加缩放级别"),  # 需要汉化: "增加缩放级别"
            enabled=False,
        )
        zoomOut = action(
            self.tr("&Zoom Out"),
            functools.partial(self.addZoom, 0.9),
            shortcuts["zoom_out"],
            "zoom-out",
            self.tr("Decrease zoom level"),
            enabled=False,
        )
        zoomOrg = action(
            self.tr("&Original size"),
            functools.partial(self.setZoom, 100),
            shortcuts["zoom_to_original"],
            "zoom",
            self.tr("Zoom to original size"),
            enabled=False,
        )
        fitWindow = action(
            self.tr("&Fit Window"),
            self.setFitWindow,
            shortcuts["fit_window"],
            "fit-window",
            self.tr("Zoom follows window size"),
            checkable=True,
            enabled=False,
        )
        fitWidth = action(
            self.tr("Fit &Width"),
            self.setFitWidth,
            shortcuts["fit_width"],
            "fit-width",
            self.tr("Zoom follows window width"),
            checkable=True,
            enabled=False,
        )
        brightnessContrast = action(
            "亮度对比度(&B)",
            self.brightnessContrast,
            None,
            "color",
            "调整亮度和对比度",
            enabled=False,
        )
        # Group zoom controls into a list for easier toggling.
        zoomActions = (
            self.zoomWidget,
            zoomIn,
            zoomOut,
            zoomOrg,
            fitWindow,
            fitWidth,
        )
        self.zoomMode = self.FIT_WINDOW
        fitWindow.setChecked(Qt.Checked)
        self.scalers = {
            self.FIT_WINDOW: self.scaleFitWindow,
            self.FIT_WIDTH: self.scaleFitWidth,
            # Set to one to scale to 100% when loading files.
            self.MANUAL_ZOOM: lambda: 1,
        }

        edit = action(
            self.tr("&Edit Label"),
            self.editLabel,
            shortcuts["edit_label"],
            "edit",
            self.tr("Modify the label of the selected polygon"),
            enabled=False,
        )

        fill_drawing = action(
            self.tr("Fill Drawing Polygon"),
            self.canvas.setFillDrawing,
            None,
            "color",
            self.tr("Fill polygon while drawing"),
            checkable=True,
            enabled=True,
        )
        fill_drawing.trigger()

        # Lavel list context menu.
        labelMenu = QtWidgets.QMenu()
        utils.addActions(labelMenu, (edit, delete))
        self.labelList.setContextMenuPolicy(Qt.CustomContextMenu)
        self.labelList.customContextMenuRequested.connect(
            self.popLabelListMenu
        )

        # Store actions for further handling.
        self.actions = utils.struct(
            saveAuto=saveAuto,
            saveWithImageData=saveWithImageData,
            changeOutputDir=changeOutputDir,
            save=save,
            saveAs=saveAs,
            open=open_,
            close=close,
            deleteFile=deleteFile,
            toggleKeepPrevMode=toggle_keep_prev_mode,
            delete=delete,
            edit=edit,
            copy=copy,
            undoLastPoint=undoLastPoint,
            undo=undo,
            addPointToEdge=addPointToEdge,
            removePoint=removePoint,
            createMode=createMode,
            editMode=editMode,
            createRectangleMode=createRectangleMode,
            createCircleMode=createCircleMode,
            createLineMode=createLineMode,
            createPointMode=createPointMode,
            createLineStripMode=createLineStripMode,
            zoom=zoom,
            zoomIn=zoomIn,
            zoomOut=zoomOut,
            zoomOrg=zoomOrg,
            fitWindow=fitWindow,
            fitWidth=fitWidth,
            brightnessContrast=brightnessContrast,
            zoomActions=zoomActions,
            openNextImg=openNextImg,
            openPrevImg=openPrevImg,
            fileMenuActions=(open_, opendir, save, saveAs, close, quit),
            tool=(),
            # XXX: need to add some actions here to activate the shortcut
            editMenu=(
                edit,
                copy,
                delete,
                None,
                undo,
                undoLastPoint,
                None,
                addPointToEdge,
                None,
                toggle_keep_prev_mode,
            ),
            # menu shown at right click
            menu=(
                createMode,
                createRectangleMode,
                createCircleMode,
                createLineMode,
                createPointMode,
                createLineStripMode,
                editMode,
                edit,
                copy,
                delete,
                undo,
                undoLastPoint,
                addPointToEdge,
                removePoint,
            ),
            onLoadActive=(
                close,
                createMode,
                createRectangleMode,
                createCircleMode,
                createLineMode,
                createPointMode,
                createLineStripMode,
                editMode,
                brightnessContrast,
            ),
            onShapesPresent=(saveAs, hideAll, showAll),
        )

        self.canvas.edgeSelected.connect(self.canvasShapeEdgeSelected)
        self.canvas.vertexSelected.connect(self.actions.removePoint.setEnabled)

        # 修改菜单栏文本
        self.menus = utils.struct(
            file=self.menu(self.tr("文件(&F)")),
            edit=self.menu(self.tr("编辑(&E)")), 
            view=self.menu(self.tr("视图(&V)")),
            help=self.menu(self.tr("帮助(&H)")),
            recentFiles=QtWidgets.QMenu(self.tr("最近打开(&R)")),
            labelList=labelMenu,
        )


        utils.addActions(
            self.menus.file,
            (
                open_,
                openNextImg,
                openPrevImg,
                opendir,
                self.menus.recentFiles,
                save,
                saveAs,
                saveAuto,
                changeOutputDir,
                saveWithImageData,
                close,
                deleteFile,
                None,
                quit,
            ),
        )
        utils.addActions(self.menus.help, (help,))
        utils.addActions(
            self.menus.view,
            (
                self.flag_dock.toggleViewAction(),
                self.label_dock.toggleViewAction(),
                self.shape_dock.toggleViewAction(),
                self.file_dock.toggleViewAction(),
                None,
                fill_drawing,
                None,
                hideAll,
                showAll,
                None,
                zoomIn,
                zoomOut,
                zoomOrg,
                None,
                fitWindow,
                fitWidth,
                None,
                brightnessContrast,
            ),
        )

        self.menus.file.aboutToShow.connect(self.updateFileMenu)

        # Custom context menu for the canvas widget:
        utils.addActions(self.canvas.menus[0], self.actions.menu)
        utils.addActions(
            self.canvas.menus[1],
            (
                action("复制到此处(&C)", self.copyShape),
                action("移动到此处(&M)", self.moveShape),
            ),
        )

        self.tools = self.toolbar("Tools")
        # Menu buttons on Left
        self.actions.tool = (
            open_,
            opendir,
            openNextImg,
            openPrevImg,
            save,
            deleteFile,
            None,
            createMode,
            editMode,
            copy,
            delete,
            undo,
            brightnessContrast,
            None,
            zoom,
            fitWidth,
        )

        self.statusBar().showMessage(self.tr("%s 已启动.") % __appname__)
        self.statusBar().show()

        if output_file is not None and self._config["auto_save"]:
            logger.warn(
                "如果`auto_save`参数为True，`output_file`参数 "
                "将被忽略，输出文件名将自动"
                "设置为IMAGE_BASENAME.json。"
            )
        self.output_file = output_file
        self.output_dir = output_dir

        # Application state.
        self.image = QtGui.QImage()
        self.imagePath = None
        self.recentFiles = []
        self.maxRecent = 7
        self.otherData = None
        self.zoom_level = 100
        self.fit_window = False
        self.zoom_values = {}  # key=filename, value=(zoom_mode, zoom_value)
        self.brightnessContrast_values = {}
        self.scroll_values = {
            Qt.Horizontal: {},
            Qt.Vertical: {},
        }  # key=filename, value=scroll_value

        if filename is not None and osp.isdir(filename):
            self.importDirImages(filename, load=False)
        else:
            self.filename = filename

        if config["file_search"]:
            self.fileSearch.setText(config["file_search"])
            self.fileSearchChanged()

        # XXX: Could be completely declarative.
        # Restore application settings.
        self.settings = QtCore.QSettings("labelme", "labelme")
        # FIXME: QSettings.value can return None on PyQt4
        self.recentFiles = self.settings.value("recentFiles", []) or []
        size = self.settings.value("window/size", QtCore.QSize(600, 500))
        position = self.settings.value("window/position", QtCore.QPoint(0, 0))
        self.resize(size)
        self.move(position)
        # or simply:
        # self.restoreGeometry(settings['window/geometry']
        self.restoreState(
            self.settings.value("window/state", QtCore.QByteArray())
        )

        # Populate the File menu dynamically.
        self.updateFileMenu()
        # Since loading the file may take some time,
        # make sure it runs in the background.
        if self.filename is not None:
            self.queueEvent(functools.partial(self.loadFile, self.filename))

        # Callbacks:
        self.zoomWidget.valueChanged.connect(self.paintCanvas)

        self.populateModeActions()

        # self.firstStart = True
        # if self.firstStart:
        #    QWhatsThis.enterWhatsThisMode()

    def menu(self, title, actions=None):
        menu = self.menuBar().addMenu(title)
        if actions:
            utils.addActions(menu, actions)
        return menu

    def toolbar(self, title, actions=None):
        toolbar = ToolBar(title)
        toolbar.setObjectName("%sToolBar" % title)
        # toolbar.setOrientation(Qt.Vertical)
        toolbar.setToolButtonStyle(Qt.ToolButtonTextUnderIcon)
        if actions:
            utils.addActions(toolbar, actions)
        self.addToolBar(Qt.LeftToolBarArea, toolbar)
        return toolbar

    # Support Functions

    def noShapes(self):
        return not len(self.labelList)

    def populateModeActions(self):
        tool, menu = self.actions.tool, self.actions.menu
        self.tools.clear()
        utils.addActions(self.tools, tool)
        self.canvas.menus[0].clear()
        utils.addActions(self.canvas.menus[0], menu)
        self.menus.edit.clear()
        actions = (
            self.actions.createMode,
            self.actions.createRectangleMode,
            self.actions.createCircleMode,
            self.actions.createLineMode,
            self.actions.createPointMode,
            self.actions.createLineStripMode,
            self.actions.editMode,
        )
        utils.addActions(self.menus.edit, actions + self.actions.editMenu)

    def setDirty(self):
        if self._config["auto_save"] or self.actions.saveAuto.isChecked():
            label_file = osp.splitext(self.imagePath)[0] + ".json"
            if self.output_dir:
                label_file_without_path = osp.basename(label_file)
                label_file = osp.join(self.output_dir, label_file_without_path)
            self.saveLabels(label_file)
            return
        self.dirty = True
        self.actions.save.setEnabled(True)
        self.actions.undo.setEnabled(self.canvas.isShapeRestorable)
        title = __appname__
        if self.filename is not None:
            title = "{} - {}*".format(title, self.filename)
        self.setWindowTitle(title)

    def setClean(self):
        self.dirty = False
        self.actions.save.setEnabled(False)
        self.actions.createMode.setEnabled(True)
        self.actions.createRectangleMode.setEnabled(True)
        self.actions.createCircleMode.setEnabled(True)
        self.actions.createLineMode.setEnabled(True)
        self.actions.createPointMode.setEnabled(True)
        self.actions.createLineStripMode.setEnabled(True)
        title = __appname__
        if self.filename is not None:
            title = "{} - {}".format(title, self.filename)
        self.setWindowTitle(title)

        if self.hasLabelFile():
            self.actions.deleteFile.setEnabled(True)
        else:
            self.actions.deleteFile.setEnabled(False)

    def toggleActions(self, value=True):
        """Enable/Disable widgets which depend on an opened image."""
        for z in self.actions.zoomActions:
            z.setEnabled(value)
        for action in self.actions.onLoadActive:
            action.setEnabled(value)

    def canvasShapeEdgeSelected(self, selected, shape):
        self.actions.addPointToEdge.setEnabled(
            selected and shape and shape.canAddPoint()
        )

    def queueEvent(self, function):
        QtCore.QTimer.singleShot(0, function)

    def status(self, message, delay=5000):
        self.statusBar().showMessage(message, delay)

    def resetState(self):
        self.labelList.clear()
        self.filename = None
        self.imagePath = None
        self.imageData = None
        self.labelFile = None
        self.otherData = None
        self.canvas.resetState()

    def currentItem(self):
        items = self.labelList.selectedItems()
        if items:
            return items[0]
        return None

    def addRecentFile(self, filename):
        if filename in self.recentFiles:
            self.recentFiles.remove(filename)
        elif len(self.recentFiles) >= self.maxRecent:
            self.recentFiles.pop()
        self.recentFiles.insert(0, filename)

    # Callbacks

    def undoShapeEdit(self):
        self.canvas.restoreShape()
        self.labelList.clear()
        self.loadShapes(self.canvas.shapes)
        self.actions.undo.setEnabled(self.canvas.isShapeRestorable)

    def tutorial(self):
        url = "https://github.com/wkentaro/labelme/tree/master/examples/tutorial"  # NOQA
        webbrowser.open(url)

    def toggleDrawingSensitive(self, drawing=True):
        """Toggle drawing sensitive.

        In the middle of drawing, toggling between modes should be disabled.
        """
        self.actions.editMode.setEnabled(not drawing)
        self.actions.undoLastPoint.setEnabled(drawing)
        self.actions.undo.setEnabled(not drawing)
        self.actions.delete.setEnabled(not drawing)

    def toggleDrawMode(self, edit=True, createMode="polygon"):
        self.canvas.setEditing(edit)
        self.canvas.createMode = createMode
        if edit:
            self.actions.createMode.setEnabled(True)
            self.actions.createRectangleMode.setEnabled(True)
            self.actions.createCircleMode.setEnabled(True)
            self.actions.createLineMode.setEnabled(True)
            self.actions.createPointMode.setEnabled(True)
            self.actions.createLineStripMode.setEnabled(True)
        else:
            if createMode == "polygon":
                self.actions.createMode.setEnabled(False)
                self.actions.createRectangleMode.setEnabled(True)
                self.actions.createCircleMode.setEnabled(True)
                self.actions.createLineMode.setEnabled(True)
                self.actions.createPointMode.setEnabled(True)
                self.actions.createLineStripMode.setEnabled(True)
            elif createMode == "rectangle":
                self.actions.createMode.setEnabled(True)
                self.actions.createRectangleMode.setEnabled(False)
                self.actions.createCircleMode.setEnabled(True)
                self.actions.createLineMode.setEnabled(True)
                self.actions.createPointMode.setEnabled(True)
                self.actions.createLineStripMode.setEnabled(True)
            elif createMode == "line":
                self.actions.createMode.setEnabled(True)
                self.actions.createRectangleMode.setEnabled(True)
                self.actions.createCircleMode.setEnabled(True)
                self.actions.createLineMode.setEnabled(False)
                self.actions.createPointMode.setEnabled(True)
                self.actions.createLineStripMode.setEnabled(True)
            elif createMode == "point":
                self.actions.createMode.setEnabled(True)
                self.actions.createRectangleMode.setEnabled(True)
                self.actions.createCircleMode.setEnabled(True)
                self.actions.createLineMode.setEnabled(True)
                self.actions.createPointMode.setEnabled(False)
                self.actions.createLineStripMode.setEnabled(True)
            elif createMode == "circle":
                self.actions.createMode.setEnabled(True)
                self.actions.createRectangleMode.setEnabled(True)
                self.actions.createCircleMode.setEnabled(False)
                self.actions.createLineMode.setEnabled(True)
                self.actions.createPointMode.setEnabled(True)
                self.actions.createLineStripMode.setEnabled(True)
            elif createMode == "linestrip":
                self.actions.createMode.setEnabled(True)
                self.actions.createRectangleMode.setEnabled(True)
                self.actions.createCircleMode.setEnabled(True)
                self.actions.createLineMode.setEnabled(True)
                self.actions.createPointMode.setEnabled(True)
                self.actions.createLineStripMode.setEnabled(False)
            else:
                raise ValueError("Unsupported createMode: %s" % createMode)
        self.actions.editMode.setEnabled(not edit)

    def setEditMode(self):
        self.toggleDrawMode(True)

    def updateFileMenu(self):
        current = self.filename

        def exists(filename):
            return osp.exists(str(filename))

        menu = self.menus.recentFiles
        menu.clear()
        files = [f for f in self.recentFiles if f != current and exists(f)]
        for i, f in enumerate(files):
            icon = utils.newIcon("labels")
            action = QtWidgets.QAction(
                icon, "&%d %s" % (i + 1, QtCore.QFileInfo(f).fileName()), self
            )
            action.triggered.connect(functools.partial(self.loadRecent, f))
            menu.addAction(action)

    def popLabelListMenu(self, point):
        self.menus.labelList.exec_(self.labelList.mapToGlobal(point))

    def validateLabel(self, label):
        # no validation
        if self._config["validate_label"] is None:
            return True

        for i in range(self.uniqLabelList.count()):
            label_i = self.uniqLabelList.item(i).data(Qt.UserRole)
            if self._config["validate_label"] in ["exact"]:
                if label_i == label:
                    return True
        return False

    def editLabel(self, item=None):
        if item and not isinstance(item, LabelListWidgetItem):
            raise TypeError("item must be LabelListWidgetItem type")

        if not self.canvas.editing():
            return
        if not item:
            item = self.currentItem()
        if item is None:
            return
        shape = item.shape()
        if shape is None:
            return
        text, flags, group_id = self.labelDialog.popUp(
            text=shape.label, flags=shape.flags, group_id=shape.group_id,
        )
        if text is None:
            return
        if not self.validateLabel(text):
            self.errorMessage(
                self.tr("无效标签"),
                self.tr("标签'{}'验证类型'{}'无效").format(
                    text, self._config["validate_label"]
                ),
            )
            return
        shape.label = text
        shape.flags = flags
        shape.group_id = group_id
        if shape.group_id is None:
            item.setText(shape.label)
        else:
            item.setText("{} ({})".format(shape.label, shape.group_id))
        self.setDirty()
        if not self.uniqLabelList.findItemsByLabel(shape.label):
            item = QtWidgets.QListWidgetItem()
            item.setData(Qt.UserRole, shape.label)
            self.uniqLabelList.addItem(item)

    def fileSearchChanged(self):
        self.importDirImages(
            self.lastOpenDir, pattern=self.fileSearch.text(), load=False,
        )

    def fileSelectionChanged(self):
        items = self.fileListWidget.selectedItems()
        if not items:
            return
        item = items[0]

        if not self.mayContinue():
            return

        currIndex = self.imageList.index(str(item.text()))
        if currIndex < len(self.imageList):
            filename = self.imageList[currIndex]
            if filename:
                self.loadFile(filename)

    # React to canvas signals.
    def shapeSelectionChanged(self, selected_shapes):
        self._noSelectionSlot = True
        for shape in self.canvas.selectedShapes:
            shape.selected = False
        self.labelList.clearSelection()
        self.canvas.selectedShapes = selected_shapes
        for shape in self.canvas.selectedShapes:
            shape.selected = True
            item = self.labelList.findItemByShape(shape)
            self.labelList.selectItem(item)
            self.labelList.scrollToItem(item)
        self._noSelectionSlot = False
        n_selected = len(selected_shapes)
        self.actions.delete.setEnabled(n_selected)
        self.actions.copy.setEnabled(n_selected)
        self.actions.edit.setEnabled(n_selected == 1)

    def addLabel(self, shape):
        if shape.group_id is None:
            text = shape.label
        else:
            text = "{} ({})".format(shape.label, shape.group_id)
        label_list_item = LabelListWidgetItem(text, shape)
        self.labelList.addItem(label_list_item)
        if not self.uniqLabelList.findItemsByLabel(shape.label):
            item = self.uniqLabelList.createItemFromLabel(shape.label)
            self.uniqLabelList.addItem(item)
            rgb = self._get_rgb_by_label(shape.label)
            self.uniqLabelList.setItemLabel(item, shape.label, rgb)
        self.labelDialog.addLabelHistory(shape.label)
        for action in self.actions.onShapesPresent:
            action.setEnabled(True)

        rgb = self._get_rgb_by_label(shape.label)

        r, g, b = rgb
        label_list_item.setText(
            '{} ●'.format(
                text, r, g, b
            )
        )
        shape.line_color = QtGui.QColor(r, g, b)
        shape.vertex_fill_color = QtGui.QColor(r, g, b)
        shape.hvertex_fill_color = QtGui.QColor(255, 255, 255)
        shape.fill_color = QtGui.QColor(r, g, b, 128)
        shape.select_line_color = QtGui.QColor(255, 255, 255)
        shape.select_fill_color = QtGui.QColor(r, g, b, 155)

    def _get_rgb_by_label(self, label):
        if self._config["shape_color"] == "auto":
            item = self.uniqLabelList.findItemsByLabel(label)[0]
            label_id = self.uniqLabelList.indexFromItem(item).row() + 1
            label_id += self._config["shift_auto_shape_color"]
            return LABEL_COLORMAP[label_id % len(LABEL_COLORMAP)]
        elif (
            self._config["shape_color"] == "manual"
            and self._config["label_colors"]
            and label in self._config["label_colors"]
        ):
            return self._config["label_colors"][label]
        elif self._config["default_shape_color"]:
            return self._config["default_shape_color"]

    def remLabels(self, shapes):
        for shape in shapes:
            item = self.labelList.findItemByShape(shape)
            self.labelList.removeItem(item)

    def loadShapes(self, shapes, replace=True):
        self._noSelectionSlot = True
        for shape in shapes:
            self.addLabel(shape)
        self.labelList.clearSelection()
        self._noSelectionSlot = False
        self.canvas.loadShapes(shapes, replace=replace)

    def loadLabels(self, shapes):
        s = []
        for shape in shapes:
            label = shape["label"]
            points = shape["points"]
            shape_type = shape["shape_type"]
            flags = shape["flags"]
            group_id = shape["group_id"]
            other_data = shape["other_data"]

            shape = Shape(
                label=label, shape_type=shape_type, group_id=group_id,
            )
            for x, y in points:
                shape.addPoint(QtCore.QPointF(x, y))
            shape.close()

            default_flags = {}
            if self._config["label_flags"]:
                for pattern, keys in self._config["label_flags"].items():
                    if re.match(pattern, label):
                        for key in keys:
                            default_flags[key] = False
            shape.flags = default_flags
            shape.flags.update(flags)
            shape.other_data = other_data

            s.append(shape)
        self.loadShapes(s)

    def loadFlags(self, flags):
        self.flag_widget.clear()
        for key, flag in flags.items():
            item = QtWidgets.QListWidgetItem(key)
            item.setFlags(item.flags() | Qt.ItemIsUserCheckable)
            item.setCheckState(Qt.Checked if flag else Qt.Unchecked)
            self.flag_widget.addItem(item)

    def saveLabels(self, filename):
        lf = LabelFile()

        def format_shape(s):
            data = s.other_data.copy()
            data.update(
                dict(
                    label=s.label.encode("utf-8") if PY2 else s.label,
                    points=[(p.x(), p.y()) for p in s.points],
                    group_id=s.group_id,
                    shape_type=s.shape_type,
                    flags=s.flags,
                )
            )
            return data

        shapes = [format_shape(item.shape()) for item in self.labelList]
        flags = {}
        for i in range(self.flag_widget.count()):
            item = self.flag_widget.item(i)
            key = item.text()
            flag = item.checkState() == Qt.Checked
            flags[key] = flag
        try:
            imagePath = osp.relpath(self.imagePath, osp.dirname(filename))
            imageData = self.imageData if self._config["store_data"] else None
            if osp.dirname(filename) and not osp.exists(osp.dirname(filename)):
                os.makedirs(osp.dirname(filename))
            lf.save(
                filename=filename,
                shapes=shapes,
                imagePath=imagePath,
                imageData=imageData,
                imageHeight=self.image.height(),
                imageWidth=self.image.width(),
                otherData=self.otherData,
                flags=flags,
            )
            self.labelFile = lf
            items = self.fileListWidget.findItems(
                self.imagePath, Qt.MatchExactly
            )
            if len(items) > 0:
                if len(items) != 1:
                    raise RuntimeError("There are duplicate files.")
                items[0].setCheckState(Qt.Checked)
            # disable allows next and previous image to proceed
            # self.filename = filename
            return True
        except LabelFileError as e:
            self.errorMessage(
                self.tr("Error saving label data"), self.tr("%s") % e
            )
            return False

    def copySelectedShape(self):
        added_shapes = self.canvas.copySelectedShapes()
        self.labelList.clearSelection()
        for shape in added_shapes:
            self.addLabel(shape)
        self.setDirty()

    def labelSelectionChanged(self):
        if self._noSelectionSlot:
            return
        if self.canvas.editing():
            selected_shapes = []
            for item in self.labelList.selectedItems():
                selected_shapes.append(item.shape())
            if selected_shapes:
                self.canvas.selectShapes(selected_shapes)
            else:
                self.canvas.deSelectShape()

    def labelItemChanged(self, item):
        shape = item.shape()
        self.canvas.setShapeVisible(shape, item.checkState() == Qt.Checked)

    def labelOrderChanged(self):
        self.setDirty()
        self.canvas.loadShapes([item.shape() for item in self.labelList])

    # Callback functions:

    def newShape(self):
        """Pop-up and give focus to the label editor.

        position MUST be in global coordinates.
        """
        items = self.uniqLabelList.selectedItems()
        text = None
        if items:
            text = items[0].data(Qt.UserRole)
        flags = {}
        group_id = None
        if self._config["display_label_popup"] or not text:
            previous_text = self.labelDialog.edit.text()
            text, flags, group_id = self.labelDialog.popUp(text)
            if not text:
                self.labelDialog.edit.setText(previous_text)

        if text and not self.validateLabel(text):
            self.errorMessage(
                self.tr("无效标签"),
                self.tr("标签'{}'验证类型'{}'无效").format(
                    text, self._config["validate_label"]
                ),
            )
            text = ""
        if text:
            self.labelList.clearSelection()
            shape = self.canvas.setLastLabel(text, flags)
            shape.group_id = group_id
            self.addLabel(shape)
            self.actions.editMode.setEnabled(True)
            self.actions.undoLastPoint.setEnabled(False)
            self.actions.undo.setEnabled(True)
            self.setDirty()
        else:
            self.canvas.undoLastLine()
            self.canvas.shapesBackups.pop()

    def scrollRequest(self, delta, orientation):
        units = -delta * 0.1  # natural scroll
        bar = self.scrollBars[orientation]
        value = bar.value() + bar.singleStep() * units
        self.setScroll(orientation, value)

    def setScroll(self, orientation, value):
        self.scrollBars[orientation].setValue(value)
        self.scroll_values[orientation][self.filename] = value

    def setZoom(self, value):
        self.actions.fitWidth.setChecked(False)
        self.actions.fitWindow.setChecked(False)
        self.zoomMode = self.MANUAL_ZOOM
        self.zoomWidget.setValue(value)
        self.zoom_values[self.filename] = (self.zoomMode, value)

    def addZoom(self, increment=1.1):
        self.setZoom(self.zoomWidget.value() * increment)

    def zoomRequest(self, delta, pos):
        canvas_width_old = self.canvas.width()
        units = 1.1
        if delta < 0:
            units = 0.9
        self.addZoom(units)

        canvas_width_new = self.canvas.width()
        if canvas_width_old != canvas_width_new:
            canvas_scale_factor = canvas_width_new / canvas_width_old

            x_shift = round(pos.x() * canvas_scale_factor) - pos.x()
            y_shift = round(pos.y() * canvas_scale_factor) - pos.y()

            self.setScroll(
                Qt.Horizontal,
                self.scrollBars[Qt.Horizontal].value() + x_shift,
            )
            self.setScroll(
                Qt.Vertical, self.scrollBars[Qt.Vertical].value() + y_shift,
            )

    def setFitWindow(self, value=True):
        if value:
            self.actions.fitWidth.setChecked(False)
        self.zoomMode = self.FIT_WINDOW if value else self.MANUAL_ZOOM
        self.adjustScale()

    def setFitWidth(self, value=True):
        if value:
            self.actions.fitWindow.setChecked(False)
        self.zoomMode = self.FIT_WIDTH if value else self.MANUAL_ZOOM
        self.adjustScale()

    def onNewBrightnessContrast(self, qimage):
        self.canvas.loadPixmap(
            QtGui.QPixmap.fromImage(qimage), clear_shapes=False
        )

    def brightnessContrast(self, value):
        dialog = BrightnessContrastDialog(
            utils.img_data_to_pil(self.imageData),
            self.onNewBrightnessContrast,
            parent=self,
        )
        brightness, contrast = self.brightnessContrast_values.get(
            self.filename, (None, None)
        )
        if brightness is not None:
            dialog.slider_brightness.setValue(brightness)
        if contrast is not None:
            dialog.slider_contrast.setValue(contrast)
        dialog.exec_()

        brightness = dialog.slider_brightness.value()
        contrast = dialog.slider_contrast.value()
        self.brightnessContrast_values[self.filename] = (brightness, contrast)

    def togglePolygons(self, value):
        for item in self.labelList:
            item.setCheckState(Qt.Checked if value else Qt.Unchecked)

    def loadFile(self, filename=None):
        """Load the specified file, or the last opened file if None."""
        # changing fileListWidget loads file
        if filename in self.imageList and (
            self.fileListWidget.currentRow() != self.imageList.index(filename)
        ):
            self.fileListWidget.setCurrentRow(self.imageList.index(filename))
            self.fileListWidget.repaint()
            return

        self.resetState()
        self.canvas.setEnabled(False)
        if filename is None:
            filename = self.settings.value("filename", "")
        filename = str(filename)
        if not QtCore.QFile.exists(filename):
            self.errorMessage(
                self.tr("打开文件错误"),
                self.tr("文件不存在: %s") % filename,
            )
            return False
        # assumes same name, but json extension
        self.status(self.tr("Loading %s...") % osp.basename(str(filename)))
        label_file = osp.splitext(filename)[0] + ".json"
        if self.output_dir:
            label_file_without_path = osp.basename(label_file)
            label_file = osp.join(self.output_dir, label_file_without_path)
        if QtCore.QFile.exists(label_file) and LabelFile.is_label_file(
            label_file
        ):
            try:
                self.labelFile = LabelFile(label_file)
            except LabelFileError as e:
                self.errorMessage(
                    self.tr("打开文件错误"),
                    self.tr(
                        "
%s
"
                        "
Make sure %s is a valid label file."
                    )
                    % (e, label_file),
                )
                self.status(self.tr("Error reading %s") % label_file)
                return False
            self.imageData = self.labelFile.imageData
            self.imagePath = osp.join(
                osp.dirname(label_file), self.labelFile.imagePath,
            )
            self.otherData = self.labelFile.otherData
        else:
            self.imageData = LabelFile.load_image_file(filename)
            if self.imageData:
                self.imagePath = filename
            self.labelFile = None
        image = QtGui.QImage.fromData(self.imageData)

        if image.isNull():
            formats = [
                "*.{}".format(fmt.data().decode())
                for fmt in QtGui.QImageReader.supportedImageFormats()
            ]
            self.errorMessage(
                self.tr("打开文件错误"),
                self.tr(
                    "
请确保 {0} 是有效的图像文件。
"
                    "支持的图像格式: {1}
"
                ).format(filename, ",".join(formats)),
            )
            self.status(self.tr("Error reading %s") % filename)
            return False
        self.image = image
        self.filename = filename
        if self._config["keep_prev"]:
            prev_shapes = self.canvas.shapes
        self.canvas.loadPixmap(QtGui.QPixmap.fromImage(image))
        flags = {k: False for k in self._config["flags"] or []}
        if self.labelFile:
            self.loadLabels(self.labelFile.shapes)
            if self.labelFile.flags is not None:
                flags.update(self.labelFile.flags)
        self.loadFlags(flags)
        if self._config["keep_prev"] and self.noShapes():
            self.loadShapes(prev_shapes, replace=False)
            self.setDirty()
        else:
            self.setClean()
        self.canvas.setEnabled(True)
        # set zoom values
        is_initial_load = not self.zoom_values
        if self.filename in self.zoom_values:
            self.zoomMode = self.zoom_values[self.filename][0]
            self.setZoom(self.zoom_values[self.filename][1])
        elif is_initial_load or not self._config["keep_prev_scale"]:
            self.adjustScale(initial=True)
        # set scroll values
        for orientation in self.scroll_values:
            if self.filename in self.scroll_values[orientation]:
                self.setScroll(
                    orientation, self.scroll_values[orientation][self.filename]
                )
        # set brightness constrast values
        dialog = BrightnessContrastDialog(
            utils.img_data_to_pil(self.imageData),
            self.onNewBrightnessContrast,
            parent=self,
        )
        brightness, contrast = self.brightnessContrast_values.get(
            self.filename, (None, None)
        )
        if self._config["keep_prev_brightness"] and self.recentFiles:
            brightness, _ = self.brightnessContrast_values.get(
                self.recentFiles[0], (None, None)
            )
        if self._config["keep_prev_contrast"] and self.recentFiles:
            _, contrast = self.brightnessContrast_values.get(
                self.recentFiles[0], (None, None)
            )
        if brightness is not None:
            dialog.slider_brightness.setValue(brightness)
        if contrast is not None:
            dialog.slider_contrast.setValue(contrast)
        self.brightnessContrast_values[self.filename] = (brightness, contrast)
        if brightness is not None or contrast is not None:
            dialog.onNewValue(None)
        self.paintCanvas()
        self.addRecentFile(self.filename)
        self.toggleActions(True)
        self.status(self.tr("Loaded %s") % osp.basename(str(filename)))
        return True

    def resizeEvent(self, event):
        if (
            self.canvas
            and not self.image.isNull()
            and self.zoomMode != self.MANUAL_ZOOM
        ):
            self.adjustScale()
        super(MainWindow, self).resizeEvent(event)

    def paintCanvas(self):
        assert not self.image.isNull(), "cannot paint null image"
        self.canvas.scale = 0.01 * self.zoomWidget.value()
        self.canvas.adjustSize()
        self.canvas.update()

    def adjustScale(self, initial=False):
        value = self.scalers[self.FIT_WINDOW if initial else self.zoomMode]()
        value = int(100 * value)
        self.zoomWidget.setValue(value)
        self.zoom_values[self.filename] = (self.zoomMode, value)

    def scaleFitWindow(self):
        """Figure out the size of the pixmap to fit the main widget."""
        e = 2.0  # So that no scrollbars are generated.
        w1 = self.centralWidget().width() - e
        h1 = self.centralWidget().height() - e
        a1 = w1 / h1
        # Calculate a new scale value based on the pixmap's aspect ratio.
        w2 = self.canvas.pixmap.width() - 0.0
        h2 = self.canvas.pixmap.height() - 0.0
        a2 = w2 / h2
        return w1 / w2 if a2 >= a1 else h1 / h2

    def scaleFitWidth(self):
        # The epsilon does not seem to work too well here.
        w = self.centralWidget().width() - 2.0
        return w / self.canvas.pixmap.width()

    def enableSaveImageWithData(self, enabled):
        self._config["store_data"] = enabled
        self.actions.saveWithImageData.setChecked(enabled)

    def closeEvent(self, event):
        if not self.mayContinue():
            event.ignore()
        self.settings.setValue(
            "filename", self.filename if self.filename else ""
        )
        self.settings.setValue("window/size", self.size())
        self.settings.setValue("window/position", self.pos())
        self.settings.setValue("window/state", self.saveState())
        self.settings.setValue("recentFiles", self.recentFiles)
        # ask the use for where to save the labels
        # self.settings.setValue('window/geometry', self.saveGeometry())

    def dragEnterEvent(self, event):
        extensions = [
            ".%s" % fmt.data().decode().lower()
            for fmt in QtGui.QImageReader.supportedImageFormats()
        ]
        if event.mimeData().hasUrls():
            items = [i.toLocalFile() for i in event.mimeData().urls()]
            if any([i.lower().endswith(tuple(extensions)) for i in items]):
                event.accept()
        else:
            event.ignore()

    def dropEvent(self, event):
        if not self.mayContinue():
            event.ignore()
            return
        items = [i.toLocalFile() for i in event.mimeData().urls()]
        self.importDroppedImageFiles(items)

    # User Dialogs #

    def loadRecent(self, filename):
        if self.mayContinue():
            self.loadFile(filename)

    def openPrevImg(self, _value=False):
        keep_prev = self._config["keep_prev"]
        if Qt.KeyboardModifiers() == (Qt.ControlModifier | Qt.ShiftModifier):
            self._config["keep_prev"] = True

        if not self.mayContinue():
            return

        if len(self.imageList) <= 0:
            return

        if self.filename is None:
            return

        currIndex = self.imageList.index(self.filename)
        if currIndex - 1 >= 0:
            filename = self.imageList[currIndex - 1]
            if filename:
                self.loadFile(filename)

        self._config["keep_prev"] = keep_prev

    def openNextImg(self, _value=False, load=True):
        keep_prev = self._config["keep_prev"]
        if Qt.KeyboardModifiers() == (Qt.ControlModifier | Qt.ShiftModifier):
            self._config["keep_prev"] = True

        if not self.mayContinue():
            return

        if len(self.imageList) <= 0:
            return

        filename = None
        if self.filename is None:
            filename = self.imageList[0]
        else:
            currIndex = self.imageList.index(self.filename)
            if currIndex + 1 < len(self.imageList):
                filename = self.imageList[currIndex + 1]
            else:
                filename = self.imageList[-1]
        self.filename = filename

        if self.filename and load:
            self.loadFile(self.filename)

        self._config["keep_prev"] = keep_prev

    def openFile(self, _value=False):
        if not self.mayContinue():
            return
        path = osp.dirname(str(self.filename)) if self.filename else "."
        formats = [
            "*.{}".format(fmt.data().decode())
            for fmt in QtGui.QImageReader.supportedImageFormats()
        ]
        filters = self.tr("图像和标签文件 (%s)") % " ".join(
            formats + ["*%s" % LabelFile.suffix]
        )
        filename = QtWidgets.QFileDialog.getOpenFileName(
            self,
            self.tr("%s - 选择图像或标签文件") % __appname__,
            path,
            filters,
        )
        if QT5:
            filename, _ = filename
        filename = str(filename)
        if filename:
            self.loadFile(filename)

    def changeOutputDirDialog(self, _value=False):
        default_output_dir = self.output_dir
        if default_output_dir is None and self.filename:
            default_output_dir = osp.dirname(self.filename)
        if default_output_dir is None:
            default_output_dir = self.currentPath()

        output_dir = QtWidgets.QFileDialog.getExistingDirectory(
            self,
            self.tr("%s - 在目录中保存/加载标注") % __appname__,
            default_output_dir,
            QtWidgets.QFileDialog.ShowDirsOnly
            | QtWidgets.QFileDialog.DontResolveSymlinks,
        )
        output_dir = str(output_dir)

        if not output_dir:
            return

        self.output_dir = output_dir

        self.statusBar().showMessage(
            self.tr("%s . 标注将保存/加载在 %s")
            % ("更改标注目录", self.output_dir)
        )
        self.statusBar().show()

        current_filename = self.filename
        self.importDirImages(self.lastOpenDir, load=False)

        if current_filename in self.imageList:
            # retain currently selected file
            self.fileListWidget.setCurrentRow(
                self.imageList.index(current_filename)
            )
            self.fileListWidget.repaint()

    def saveFile(self, _value=False):
        assert not self.image.isNull(), "cannot save empty image"
        if self.labelFile:
            # DL20180323 - overwrite when in directory
            self._saveFile(self.labelFile.filename)
        elif self.output_file:
            self._saveFile(self.output_file)
            self.close()
        else:
            self._saveFile(self.saveFileDialog())

    def saveFileAs(self, _value=False):
        assert not self.image.isNull(), "cannot save empty image"
        self._saveFile(self.saveFileDialog())

    def saveFileDialog(self):
        caption = self.tr("%s - 选择文件") % __appname__
        filters = self.tr("标签文件 (*%s)") % LabelFile.suffix
        if self.output_dir:
            dlg = QtWidgets.QFileDialog(
                self, caption, self.output_dir, filters
            )
        else:
            dlg = QtWidgets.QFileDialog(
                self, caption, self.currentPath(), filters
            )
        dlg.setDefaultSuffix(LabelFile.suffix[1:])
        dlg.setAcceptMode(QtWidgets.QFileDialog.AcceptSave)
        dlg.setOption(QtWidgets.QFileDialog.DontConfirmOverwrite, False)
        dlg.setOption(QtWidgets.QFileDialog.DontUseNativeDialog, False)
        basename = osp.basename(osp.splitext(self.filename)[0])
        if self.output_dir:
            default_labelfile_name = osp.join(
                self.output_dir, basename + LabelFile.suffix
            )
        else:
            default_labelfile_name = osp.join(
                self.currentPath(), basename + LabelFile.suffix
            )
        filename = dlg.getSaveFileName(
            self,
            self.tr("选择文件"),
            default_labelfile_name,
            self.tr("Label files (*%s)") % LabelFile.suffix,
        )
        if isinstance(filename, tuple):
            filename, _ = filename
        return filename

    def _saveFile(self, filename):
        if filename and self.saveLabels(filename):
            self.addRecentFile(filename)
            self.setClean()

    def closeFile(self, _value=False):
        if not self.mayContinue():
            return
        self.resetState()
        self.setClean()
        self.toggleActions(False)
        self.canvas.setEnabled(False)
        self.actions.saveAs.setEnabled(False)

    def getLabelFile(self):
        if self.filename.lower().endswith(".json"):
            label_file = self.filename
        else:
            label_file = osp.splitext(self.filename)[0] + ".json"

        return label_file

    def deleteFile(self):
        mb = QtWidgets.QMessageBox
        msg = self.tr(
            "你即将永久删除此标签文件 "
            "是否继续？"
        )
        answer = mb.warning(self, self.tr("注意"), msg, mb.Yes | mb.No)
        if answer != mb.Yes:
            return

        label_file = self.getLabelFile()
        if osp.exists(label_file):
            os.remove(label_file)
            logger.info("Label file is removed: {}".format(label_file))

            item = self.fileListWidget.currentItem()
            item.setCheckState(Qt.Unchecked)

            self.resetState()

    # Message Dialogs. #
    def hasLabels(self):
        if self.noShapes():
            self.errorMessage(
                "无标注对象",
                "保存文件前必须至少标注一个对象.",
            )
            return False
        return True

    def hasLabelFile(self):
        if self.filename is None:
            return False

        label_file = self.getLabelFile()
        return osp.exists(label_file)

    def mayContinue(self):
        if not self.dirty:
            return True
        mb = QtWidgets.QMessageBox
        msg = self.tr('关闭前是否保存标注到"{}"?').format(
            self.filename
        )
        answer = mb.question(
            self,
            self.tr("Save annotations?"),
            msg,
            mb.Save | mb.Discard | mb.Cancel,
            mb.Save,
        )
        if answer == mb.Discard:
            return True
        elif answer == mb.Save:
            self.saveFile()
            return True
        else:  # answer == mb.Cancel
            return False

    def errorMessage(self, title, message):
        return QtWidgets.QMessageBox.critical(
            self, title, "
%s
%s" % (title, message)
        )

    def currentPath(self):
        return osp.dirname(str(self.filename)) if self.filename else "."

    def toggleKeepPrevMode(self):
        self._config["keep_prev"] = not self._config["keep_prev"]

    def deleteSelectedShape(self):
        yes, no = QtWidgets.QMessageBox.Yes, QtWidgets.QMessageBox.No
        msg = self.tr(
            "您即将永久删除 {} 个多边形, "
            "是否继续?"
        ).format(len(self.canvas.selectedShapes))
        if yes == QtWidgets.QMessageBox.warning(
            self, self.tr("Attention"), msg, yes | no, yes
        ):
            self.remLabels(self.canvas.deleteSelected())
            self.setDirty()
            if self.noShapes():
                for action in self.actions.onShapesPresent:
                    action.setEnabled(False)

    def copyShape(self):
        self.canvas.endMove(copy=True)
        self.labelList.clearSelection()
        for shape in self.canvas.selectedShapes:
            self.addLabel(shape)
        self.setDirty()

    def moveShape(self):
        self.canvas.endMove(copy=False)
        self.setDirty()

    def openDirDialog(self, _value=False, dirpath=None):
        if not self.mayContinue():
            return

        defaultOpenDirPath = dirpath if dirpath else "."
        if self.lastOpenDir and osp.exists(self.lastOpenDir):
            defaultOpenDirPath = self.lastOpenDir
        else:
            defaultOpenDirPath = (
                osp.dirname(self.filename) if self.filename else "."
            )

        targetDirPath = str(
            QtWidgets.QFileDialog.getExistingDirectory(
                self,
                self.tr("%s - 打开目录") % __appname__,
                defaultOpenDirPath,
                QtWidgets.QFileDialog.ShowDirsOnly
                | QtWidgets.QFileDialog.DontResolveSymlinks,
            )
        )
        self.importDirImages(targetDirPath)

    @property
    def imageList(self):
        lst = []
        for i in range(self.fileListWidget.count()):
            item = self.fileListWidget.item(i)
            lst.append(item.text())
        return lst

    def importDroppedImageFiles(self, imageFiles):
        extensions = [
            ".%s" % fmt.data().decode().lower()
            for fmt in QtGui.QImageReader.supportedImageFormats()
        ]

        self.filename = None
        for file in imageFiles:
            if file in self.imageList or not file.lower().endswith(
                tuple(extensions)
            ):
                continue
            label_file = osp.splitext(file)[0] + ".json"
            if self.output_dir:
                label_file_without_path = osp.basename(label_file)
                label_file = osp.join(self.output_dir, label_file_without_path)
            item = QtWidgets.QListWidgetItem(file)
            item.setFlags(Qt.ItemIsEnabled | Qt.ItemIsSelectable)
            if QtCore.QFile.exists(label_file) and LabelFile.is_label_file(
                label_file
            ):
                item.setCheckState(Qt.Checked)
            else:
                item.setCheckState(Qt.Unchecked)
            self.fileListWidget.addItem(item)

        if len(self.imageList) > 1:
            self.actions.openNextImg.setEnabled(True)
            self.actions.openPrevImg.setEnabled(True)

        self.openNextImg()

    def importDirImages(self, dirpath, pattern=None, load=True):
        self.actions.openNextImg.setEnabled(True)
        self.actions.openPrevImg.setEnabled(True)

        if not self.mayContinue() or not dirpath:
            return

        self.lastOpenDir = dirpath
        self.filename = None
        self.fileListWidget.clear()
        for filename in self.scanAllImages(dirpath):
            if pattern and pattern not in filename:
                continue
            label_file = osp.splitext(filename)[0] + ".json"
            if self.output_dir:
                label_file_without_path = osp.basename(label_file)
                label_file = osp.join(self.output_dir, label_file_without_path)
            item = QtWidgets.QListWidgetItem(filename)
            item.setFlags(Qt.ItemIsEnabled | Qt.ItemIsSelectable)
            if QtCore.QFile.exists(label_file) and LabelFile.is_label_file(
                label_file
            ):
                item.setCheckState(Qt.Checked)
            else:
                item.setCheckState(Qt.Unchecked)
            self.fileListWidget.addItem(item)
        self.openNextImg(load=load)

    def scanAllImages(self, folderPath):
        extensions = [
            ".%s" % fmt.data().decode().lower()
            for fmt in QtGui.QImageReader.supportedImageFormats()
        ]

        images = []
        for root, dirs, files in os.walk(folderPath):
            for file in files:
                if file.lower().endswith(tuple(extensions)):
                    relativePath = osp.join(root, file)
                    images.append(relativePath)
        images.sort(key=lambda x: x.lower())
        return images