Function to zoom in corners with hotkeys

labelImg.py

@@ -309,6 +309,17 @@ def getFormatMeta(format):
         fitWidth = action(getStr('fitWidth'), self.setFitWidth,
                           'Ctrl+Shift+F', 'fit-width', getStr('fitWidthDetail'),
                           checkable=True, enabled=False)
+
+        # Zoom in corners
+        zoomLeftTop = action(getStr('zoomLT'), self.zoomLeftTop,
+                             '1', 'left-top', getStr('zoomLT'))
+        zoomRightTop = action(getStr('zoomRT'), self.zoomRightTop,
+                              '2', 'right-top', getStr('zoomRT'))
+        zoomRightBottom = action(getStr('zoomRB'), self.zoomRightBottom,
+                                 '3', 'right-bottom', getStr('zoomRB'))
+        zoomLeftBottom = action(getStr('zoomLB'), self.zoomLeftBottom,
+                                '4', 'left-bottom', getStr('zoomLB'))
+
         # Group zoom controls into a list for easier toggling.
         zoomActions = (self.zoomWidget, zoomIn, zoomOut,
                        zoomOrg, fitWindow, fitWidth)
@@ -405,7 +416,8 @@ def getFormatMeta(format):
             labels, advancedMode, None,
             hideAll, showAll, None,
             zoomIn, zoomOut, zoomOrg, None,
-            fitWindow, fitWidth))
+            fitWindow, fitWidth, None,
+            zoomLeftTop, zoomRightTop, zoomRightBottom, zoomLeftBottom))
 
         self.menus.file.aboutToShow.connect(self.updateFileMenu)
 
@@ -958,6 +970,30 @@ def setZoom(self, value):
     def addZoom(self, increment=10):
         self.setZoom(self.zoomWidget.value() + increment)
 
+    def zoomLeftTop(self):
+        self.setZoom(300)
+        h_bar = self.scrollBars[Qt.Horizontal].setValue(0)
+        v_bar = self.scrollBars[Qt.Vertical].setValue(0)
+
+    def zoomRightTop(self):
+        self.setZoom(300)
+        h_bar = self.scrollBars[Qt.Horizontal]
+        v_bar = self.scrollBars[Qt.Vertical].setValue(0)
+        h_bar.setValue(h_bar.maximum())
+
+    def zoomRightBottom(self):
+        self.setZoom(300)
+        h_bar = self.scrollBars[Qt.Horizontal]
+        v_bar = self.scrollBars[Qt.Vertical]
+        h_bar.setValue(h_bar.maximum())
+        v_bar.setValue(v_bar.maximum())
+
+    def zoomLeftBottom(self):
+        self.setZoom(300)
+        h_bar = self.scrollBars[Qt.Horizontal].setValue(0)
+        v_bar = self.scrollBars[Qt.Vertical]
+        v_bar.setValue(v_bar.maximum())
+
     def zoomRequest(self, delta):
         # get the current scrollbar positions
         # calculate the percentages ~ coordinates

resources/strings/strings.properties

@@ -46,6 +46,10 @@ fitWin=Fit Window
 fitWinDetail=Zoom follows window size
 fitWidth=Fit Width
 fitWidthDetail=Zoom follows window width
+zoomLT=Zoom left top corner
+zoomRT=Zoom right top corner
+zoomRB=Zoom right bottom corner
+zoomLB=Zoom left bottom corner
 editLabel=Edit Label
 editLabelDetail=Modify the label of the selected Box
 shapeLineColor=Shape Line Color