diff --git a/PPOCRLabel.py b/PPOCRLabel.py
index d24f8b9..4516305 100644
--- a/PPOCRLabel.py
+++ b/PPOCRLabel.py
@@ -931,6 +931,15 @@ def get_str(str_id):
             enabled=True,
         )
 
+        convertToRect = action(
+            get_str("convertToRect"),
+            self.convertToRect,
+            "Ctrl+T",
+            "edit",
+            get_str("convertToRectDetail"),
+            enabled=False,
+        )
+
         settings_action = action(
             get_str("settings"),
             self.showSettingsDialog,
@@ -1012,6 +1021,7 @@ def get_str(str_id):
             delete=delete,
             edit=edit,
             focusAndZoom=focusAndZoom,
+            convertToRect=convertToRect,
             copy=copy,
             saveRec=saveRec,
             singleRere=singleRere,
@@ -1054,6 +1064,7 @@ def get_str(str_id):
                 createpoly,
                 edit,
                 focusAndZoom,
+                convertToRect,
                 copy,
                 delete,
                 singleRere,
@@ -1078,6 +1089,7 @@ def get_str(str_id):
                 createpoly,
                 edit,
                 focusAndZoom,
+                convertToRect,
                 copy,
                 delete,
                 singleRere,
@@ -1815,6 +1827,7 @@ def shapeSelectionChanged(self, selected_shapes):
         self.actions.lock.setEnabled(n_selected)
         self.actions.change_cls.setEnabled(n_selected)
         self.actions.expand.setEnabled(n_selected)
+        self.actions.convertToRect.setEnabled(n_selected > 0)
 
     def addLabel(self, shape):
         shape.paintLabel = self.displayLabelOption.isChecked()
@@ -3868,70 +3881,115 @@ def get_top_left(rect):
             [max(p[1] for p in rect) - min(p[1] for p in rect) for rect in rectangles]
         ) / len(rectangles)
         threshold = avg_height * row_height_threshold
+
+        # Keep track of original indices to handle duplicates correctly
         indexed_rects = [(i, get_top_left(rect)) for i, rect in enumerate(rectangles)]
         indexed_rects.sort(key=lambda x: x[1][1])
+
         rows = []
         current_row = []
-        last_y = indexed_rects[0][1][1]
-        for item in indexed_rects:
-            i, (x, y) = item
-            if abs(y - last_y) <= threshold:
-                current_row.append(item)
-            else:
+        if indexed_rects:
+            last_y = indexed_rects[0][1][1]
+            for item in indexed_rects:
+                i, (x, y) = item
+                if abs(y - last_y) <= threshold:
+                    current_row.append(item)
+                else:
+                    rows.append(current_row)
+                    current_row = [item]
+                last_y = y
+            if current_row:
                 rows.append(current_row)
-                current_row = [item]
-            last_y = y
-        if current_row:
-            rows.append(current_row)
-        sorted_rects = []
+
+        sorted_indices = []
         for row in rows:
             row.sort(key=lambda x: x[1][0])
-            sorted_rects.extend([rectangles[i] for i, _ in row])
-        return sorted_rects
+            sorted_indices.extend([i for i, _ in row])
+        return sorted_indices
 
     def resortBoxPosition(self):
-        # get original elements
-        items = []
-        for i in range(self.BoxList.count()):
-            item = self.BoxList.item(i)
-            items.append({"text": item.text(), "object": item})
-        # get coordinate points
+        # get coordinate points from shapes directly to be more reliable
         rectangles = []
-        for item in items:
-            text = item["text"]
-            try:
-                rect = ast.literal_eval(text)  # 转为列表
-                rectangles.append(rect)
-            except (ValueError, SyntaxError) as e:
-                logger.error(f"Error parsing text: {text}")
-                continue
-        # start resort
-        sorted_rectangles = self.sort_rectangles(rectangles, row_height_threshold=0.5)
-        # old_idx <--> new_idx
-        index_map = []
-        for sorted_rect in sorted_rectangles:
-            for old_idx, rect in enumerate(rectangles):
-                if rect == sorted_rect:
-                    index_map.append(old_idx)
-                    break
-        # resort BoxList labelList canvas.shapes
-        items = [self.BoxList.takeItem(0) for _ in range(self.BoxList.count())]
+        for shape in self.canvas.shapes:
+            rect = [[int(p.x()), int(p.y())] for p in shape.points]
+            rectangles.append(rect)
+
+        if not rectangles:
+            return
+
+        # start resort - now returns indices
+        index_map = self.sort_rectangles(rectangles, row_height_threshold=0.5)
+
+        if len(index_map) != len(self.canvas.shapes):
+            logger.error("Resort failed: index map size mismatch")
+            return
+
+        # resort BoxList, labelList, and canvas.shapes
+        # Take all items out first
+        items_box = [self.BoxList.takeItem(0) for _ in range(self.BoxList.count())]
         items_label = [
             self.labelList.takeItem(0) for _ in range(self.labelList.count())
         ]
-        shapes = self.canvas.shapes
+        shapes = list(self.canvas.shapes)
+
         self.canvas.shapes = []
-        for new_idx in range(len(index_map)):
-            old_idx = index_map[new_idx]
-            self.BoxList.insertItem(new_idx, items[old_idx])
+        for new_idx, old_idx in enumerate(index_map):
+            self.BoxList.insertItem(new_idx, items_box[old_idx])
             self.labelList.insertItem(new_idx, items_label[old_idx])
-            self.canvas.shapes.insert(new_idx, shapes[old_idx])
+            self.canvas.shapes.append(shapes[old_idx])
+
+        # Update internal indices and refresh UI
+        self.updateIndexList()
+        for i, shape in enumerate(self.canvas.shapes):
+            shape.idx = i
+
+        self.canvas.update()
+        self.setDirty()
+
         QMessageBox.information(
             self,
             "Information",
             "resort success!",
         )
 
+    def convertToRect(self):
+        if not self.canvas.selectedShapes:
+            return
+
+        changed = False
+        for shape in self.canvas.selectedShapes:
+            if not shape.points:
+                continue
+
+            if len(shape.points) == 4:
+                p0, p1, p2, p3 = shape.points
+                if (
+                    p0.x() == p3.x()
+                    and p0.y() == p1.y()
+                    and p2.x() == p1.x()
+                    and p2.y() == p3.y()
+                ):
+                    continue
+
+            min_x = min(p.x() for p in shape.points)
+            max_x = max(p.x() for p in shape.points)
+            min_y = min(p.y() for p in shape.points)
+            max_y = max(p.y() for p in shape.points)
+
+            shape.points = [
+                QPointF(min_x, min_y),
+                QPointF(max_x, min_y),
+                QPointF(max_x, max_y),
+                QPointF(min_x, max_y),
+            ]
+            shape.close()
+            changed = True
+
+        if changed:
+            self.updateBoxlist()
+            self.setDirty()
+            self.canvas.repaint()
+
 
 def inverted(color):
     return QColor(*[255 - v for v in color.getRgb()])
diff --git a/README.md b/README.md
index 0f73830..de5d263 100644
--- a/README.md
+++ b/README.md
@@ -244,6 +244,7 @@ labeling in the Excel file, the recommended steps are:
 | Ctrl + R                 | Re-recognize the selected box                    |
 | Ctrl + C                 | Copy and paste the selected box                  |
 | Ctrl + B                 | Resort Bounding Box Positions |
+| Ctrl + T                 | Convert PolygonBox to RectBox |
 | Ctrl + Left Mouse Button | Multi select the label box                       |
 | Backspace or Delete      | Delete the selected box                          |
 | Ctrl + V  or End         | Check image                                      |
diff --git a/README_ch.md b/README_ch.md
index 0a26c98..cfb3c4f 100644
--- a/README_ch.md
+++ b/README_ch.md
@@ -220,6 +220,7 @@ PPOCRLabel.exe --lang ch
 | Ctrl + R         | 重新识别所选标记                        |
 | Ctrl + C         | 【复制并粘贴】选中的标记框                     |
 | Ctrl + B         | 重新排序坐标框位置                     |
+| Ctrl + T         | 将多边形框转换为矩形框                     |
 | Ctrl + 鼠标左键    | 多选标记框                           |
 | Backspace 或 Delete    | 删除所选框                           |
 | Ctrl + V 或 End        | 确认本张图片标记                        |
diff --git a/libs/autoDialog.py b/libs/autoDialog.py
index 6e605b1..4330f8c 100644
--- a/libs/autoDialog.py
+++ b/libs/autoDialog.py
@@ -72,12 +72,11 @@ def run(self):
                                     "The size of %s is too small to be recognised",
                                     img_path,
                                 )
-                                self.result_dic = None
+                                self.result_dic = []  # Clear it instead of None
 
                     # 结果保存
-                    if self.result_dic is None or len(self.result_dic) == 0:
+                    if not self.result_dic:
                         logger.warning("No text detected in file %s", img_path)
-                        pass
                     else:
                         strs = ""
                         for res in self.result_dic:
@@ -93,12 +92,16 @@ def run(self):
                                 + json.dumps(posi)
                                 + "\n"
                             )
-                        # Sending large amounts of data repeatedly through pyqtSignal may affect the program efficiency
+
                         self.listValue.emit(strs)
                         self.mainThread.result_dic = self.result_dic
                         self.mainThread.filePath = img_path
-                        # 保存
                         self.mainThread.saveFile(mode="Auto")
+                        # CRITICAL: Clear the result_dic after saving to prevent it from
+                        # leaking into the next image or back into the main UI
+                        self.mainThread.result_dic = []
+                        self.result_dic = []
+
                     findex += 1
                     self.progressBarValue.emit(findex)
                 else:
diff --git a/libs/canvas.py b/libs/canvas.py
index 14fe9e6..bf96c6b 100644
--- a/libs/canvas.py
+++ b/libs/canvas.py
@@ -472,7 +472,15 @@ def boundedMoveVertex(self, pos):
         else:
             shiftPos = pos - point
 
-        if [shape[0].x(), shape[0].y(), shape[2].x(), shape[2].y()] == [
+        # Symmetric resizing with Ctrl
+        is_ctrl_pressed = int(QApplication.keyboardModifiers()) == Qt.ControlModifier
+
+        if len(shape.points) == 4 and [
+            shape[0].x(),
+            shape[0].y(),
+            shape[2].x(),
+            shape[2].y(),
+        ] == [
             shape[3].x(),
             shape[1].y(),
             shape[1].x(),
@@ -492,8 +500,22 @@ def boundedMoveVertex(self, pos):
             shape.moveVertexBy(rindex, rshift)
             shape.moveVertexBy(lindex, lshift)
 
+            if is_ctrl_pressed:
+                opp_index = (index + 2) % 4
+                shape.moveVertexBy(opp_index, -shiftPos)
+                shape.moveVertexBy((opp_index + 1) % 4, -lshift)
+                shape.moveVertexBy((opp_index + 3) % 4, -rshift)
+
         else:
             shape.moveVertexBy(index, shiftPos)
+            if is_ctrl_pressed and len(shape.points) > 1:
+                # Calculate symmetric opposite index for simple shapes
+                if len(shape.points) == 4:
+                    opp_index = (index + 2) % 4
+                    shape.moveVertexBy(opp_index, -shiftPos)
+                elif len(shape.points) == 2:
+                    opp_index = (index + 1) % 2
+                    shape.moveVertexBy(opp_index, -shiftPos)
 
     def boundedMoveShape(self, shapes, pos):
         if type(shapes).__name__ != "list":
diff --git a/libs/resources.py b/libs/resources.py
index 1147fd7..f33c2f8 100644
--- a/libs/resources.py
+++ b/libs/resources.py
@@ -9092,7 +9092,7 @@
 \xc2\xbe\x6b\xc0\x55\xc8\x31\xa0\x80\x1e\x20\x21\xee\xf8\x2f\xe5\
 \xea\x8d\x7f\x05\xf8\x03\xd8\xcb\xf0\xd4\x8e\x80\x5e\x37\x00\x00\
 \x00\x00\x49\x45\x4e\x44\xae\x42\x60\x82\
-\x00\x00\x0e\x91\
+\x00\x00\x0e\xe9\
 \x73\
 \x61\x76\x65\x41\x73\x44\x65\x74\x61\x69\x6c\x3d\xe5\xb0\x87\xe6\
 \xa0\x87\xe7\xad\xbe\xe4\xbf\x9d\xe5\xad\x98\xe5\x88\xb0\xe5\x85\
@@ -9327,7 +9327,12 @@
 \x73\x44\x65\x74\x61\x69\x6c\x3d\xe5\xba\x94\xe7\x94\xa8\xe7\xa8\
 \x8b\xe5\xba\x8f\xe8\xae\xbe\xe7\xbd\xae\x0a\x66\x6f\x6e\x74\x53\
 \x69\x7a\x65\x3d\xe5\xad\x97\xe4\xbd\x93\xe5\xa4\xa7\xe5\xb0\x8f\
-\
+\x0a\x63\x6f\x6e\x76\x65\x72\x74\x54\x6f\x52\x65\x63\x74\x3d\xe8\
+\xbd\xac\xe6\x8d\xa2\xe4\xb8\xba\xe7\x9f\xa9\xe5\xbd\xa2\xe6\xa1\
+\x86\x0a\x63\x6f\x6e\x76\x65\x72\x74\x54\x6f\x52\x65\x63\x74\x44\
+\x65\x74\x61\x69\x6c\x3d\xe5\xb0\x86\xe5\xa4\x9a\xe8\xbe\xb9\xe5\
+\xbd\xa2\xe6\xa1\x86\xe8\xbd\xac\xe6\x8d\xa2\xe4\xb8\xba\xe7\x9f\
+\xa9\xe5\xbd\xa2\xe6\xa1\x86\x0a\
 \x00\x00\x03\x12\
 \x89\
 \x50\x4e\x47\x0d\x0a\x1a\x0a\x00\x00\x00\x0d\x49\x48\x44\x52\x00\
@@ -11017,7 +11022,7 @@
 \xbe\xde\xa3\x73\x07\x05\x00\x88\x83\x48\x18\x92\xaf\x02\xff\x03\
 \x39\x5c\xc9\x23\xd1\xf6\x50\x87\x00\x00\x00\x00\x49\x45\x4e\x44\
 \xae\x42\x60\x82\
-\x00\x00\x0e\x89\
+\x00\x00\x0e\xdd\
 \x6f\
 \x70\x65\x6e\x46\x69\x6c\x65\x3d\x4f\x70\x65\x6e\x0a\x6f\x70\x65\
 \x6e\x46\x69\x6c\x65\x44\x65\x74\x61\x69\x6c\x3d\x4f\x70\x65\x6e\
@@ -11251,7 +11256,12 @@
 \x73\x0a\x73\x65\x74\x74\x69\x6e\x67\x73\x44\x65\x74\x61\x69\x6c\
 \x3d\x41\x70\x70\x6c\x69\x63\x61\x74\x69\x6f\x6e\x20\x73\x65\x74\
 \x74\x69\x6e\x67\x73\x0a\x66\x6f\x6e\x74\x53\x69\x7a\x65\x3d\x46\
-\x6f\x6e\x74\x20\x53\x69\x7a\x65\
+\x6f\x6e\x74\x20\x53\x69\x7a\x65\x0a\x63\x6f\x6e\x76\x65\x72\x74\
+\x54\x6f\x52\x65\x63\x74\x3d\x43\x6f\x6e\x76\x65\x72\x74\x20\x74\
+\x6f\x20\x52\x65\x63\x74\x42\x6f\x78\x0a\x63\x6f\x6e\x76\x65\x72\
+\x74\x54\x6f\x52\x65\x63\x74\x44\x65\x74\x61\x69\x6c\x3d\x43\x6f\
+\x6e\x76\x65\x72\x74\x20\x50\x6f\x6c\x79\x67\x6f\x6e\x42\x6f\x78\
+\x20\x74\x6f\x20\x52\x65\x63\x74\x42\x6f\x78\x0a\
 \x00\x00\x0e\x35\
 \x89\
 \x50\x4e\x47\x0d\x0a\x1a\x0a\x00\x00\x00\x0d\x49\x48\x44\x52\x00\
@@ -11654,21 +11664,21 @@
 \x00\x00\x00\xfc\x00\x00\x00\x00\x00\x01\x00\x02\x2b\xd3\
 \x00\x00\x01\x0c\x00\x00\x00\x00\x00\x01\x00\x02\x30\x8c\
 \x00\x00\x01\x20\x00\x00\x00\x00\x00\x01\x00\x02\x34\xdb\
-\x00\x00\x01\x40\x00\x00\x00\x00\x00\x01\x00\x02\x43\x70\
-\x00\x00\x01\x5a\x00\x00\x00\x00\x00\x01\x00\x02\x46\x86\
-\x00\x00\x01\x74\x00\x00\x00\x00\x00\x01\x00\x02\x4a\xd8\
-\x00\x00\x01\x8a\x00\x00\x00\x00\x00\x01\x00\x02\x4f\x0e\
-\x00\x00\x01\xa4\x00\x00\x00\x00\x00\x01\x00\x02\x58\x52\
-\x00\x00\x01\xb6\x00\x00\x00\x00\x00\x01\x00\x02\x60\xae\
-\x00\x00\x01\xc8\x00\x00\x00\x00\x00\x01\x00\x02\x62\x01\
-\x00\x00\x01\xda\x00\x00\x00\x00\x00\x01\x00\x02\x6b\x52\
-\x00\x00\x01\xf2\x00\x00\x00\x00\x00\x01\x00\x02\x70\xab\
-\x00\x00\x02\x04\x00\x00\x00\x00\x00\x01\x00\x02\x7c\x90\
-\x00\x00\x02\x20\x00\x00\x00\x00\x00\x01\x00\x02\x7f\x37\
-\x00\x00\x02\x3a\x00\x00\x00\x00\x00\x01\x00\x02\x8f\xb3\
-\x00\x00\x02\x4e\x00\x00\x00\x00\x00\x01\x00\x02\x9a\xb2\
-\x00\x00\x02\x6a\x00\x00\x00\x00\x00\x01\x00\x02\xab\x2b\
-\x00\x00\x02\x7e\x00\x00\x00\x00\x00\x01\x00\x02\xb9\xb8\
+\x00\x00\x01\x40\x00\x00\x00\x00\x00\x01\x00\x02\x43\xc8\
+\x00\x00\x01\x5a\x00\x00\x00\x00\x00\x01\x00\x02\x46\xde\
+\x00\x00\x01\x74\x00\x00\x00\x00\x00\x01\x00\x02\x4b\x30\
+\x00\x00\x01\x8a\x00\x00\x00\x00\x00\x01\x00\x02\x4f\x66\
+\x00\x00\x01\xa4\x00\x00\x00\x00\x00\x01\x00\x02\x58\xaa\
+\x00\x00\x01\xb6\x00\x00\x00\x00\x00\x01\x00\x02\x61\x06\
+\x00\x00\x01\xc8\x00\x00\x00\x00\x00\x01\x00\x02\x62\x59\
+\x00\x00\x01\xda\x00\x00\x00\x00\x00\x01\x00\x02\x6b\xaa\
+\x00\x00\x01\xf2\x00\x00\x00\x00\x00\x01\x00\x02\x71\x03\
+\x00\x00\x02\x04\x00\x00\x00\x00\x00\x01\x00\x02\x7c\xe8\
+\x00\x00\x02\x20\x00\x00\x00\x00\x00\x01\x00\x02\x7f\x8f\
+\x00\x00\x02\x3a\x00\x00\x00\x00\x00\x01\x00\x02\x90\x0b\
+\x00\x00\x02\x4e\x00\x00\x00\x00\x00\x01\x00\x02\x9b\x0a\
+\x00\x00\x02\x6a\x00\x00\x00\x00\x00\x01\x00\x02\xab\x83\
+\x00\x00\x02\x7e\x00\x00\x00\x00\x00\x01\x00\x02\xba\x64\
 "
 
 qt_resource_struct_v2 = b"\
@@ -11715,36 +11725,36 @@
 \x00\x00\x01\x0c\x00\x00\x00\x00\x00\x01\x00\x02\x30\x8c\
 \x00\x00\x01\x9c\xc0\x4e\x25\x94\
 \x00\x00\x01\x20\x00\x00\x00\x00\x00\x01\x00\x02\x34\xdb\
-\x00\x00\x01\x9d\x27\x67\x29\xa7\
-\x00\x00\x01\x40\x00\x00\x00\x00\x00\x01\x00\x02\x43\x70\
+\x00\x00\x01\x9d\x2a\x26\xbc\xd6\
+\x00\x00\x01\x40\x00\x00\x00\x00\x00\x01\x00\x02\x43\xc8\
 \x00\x00\x01\x9c\xc0\x4e\x25\x92\
-\x00\x00\x01\x5a\x00\x00\x00\x00\x00\x01\x00\x02\x46\x86\
+\x00\x00\x01\x5a\x00\x00\x00\x00\x00\x01\x00\x02\x46\xde\
 \x00\x00\x01\x9c\xc0\x4e\x25\x91\
-\x00\x00\x01\x74\x00\x00\x00\x00\x00\x01\x00\x02\x4a\xd8\
+\x00\x00\x01\x74\x00\x00\x00\x00\x00\x01\x00\x02\x4b\x30\
 \x00\x00\x01\x9c\xc0\x4e\x25\x94\
-\x00\x00\x01\x8a\x00\x00\x00\x00\x00\x01\x00\x02\x4f\x0e\
+\x00\x00\x01\x8a\x00\x00\x00\x00\x00\x01\x00\x02\x4f\x66\
 \x00\x00\x01\x9c\xc0\x4e\x25\x90\
-\x00\x00\x01\xa4\x00\x00\x00\x00\x00\x01\x00\x02\x58\x52\
+\x00\x00\x01\xa4\x00\x00\x00\x00\x00\x01\x00\x02\x58\xaa\
 \x00\x00\x01\x9c\xc0\x4e\x25\x90\
-\x00\x00\x01\xb6\x00\x00\x00\x00\x00\x01\x00\x02\x60\xae\
+\x00\x00\x01\xb6\x00\x00\x00\x00\x00\x01\x00\x02\x61\x06\
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-\x00\x00\x01\xda\x00\x00\x00\x00\x00\x01\x00\x02\x6b\x52\
+\x00\x00\x01\xda\x00\x00\x00\x00\x00\x01\x00\x02\x6b\xaa\
 \x00\x00\x01\x9c\xc0\x4e\x25\x91\
-\x00\x00\x01\xf2\x00\x00\x00\x00\x00\x01\x00\x02\x70\xab\
+\x00\x00\x01\xf2\x00\x00\x00\x00\x00\x01\x00\x02\x71\x03\
 \x00\x00\x01\x9c\xc0\x4e\x25\x94\
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+\x00\x00\x02\x04\x00\x00\x00\x00\x00\x01\x00\x02\x7c\xe8\
 \x00\x00\x01\x9c\xc0\x4e\x25\x92\
-\x00\x00\x02\x20\x00\x00\x00\x00\x00\x01\x00\x02\x7f\x37\
+\x00\x00\x02\x20\x00\x00\x00\x00\x00\x01\x00\x02\x7f\x8f\
 \x00\x00\x01\x9c\xc0\x4e\x25\x93\
-\x00\x00\x02\x3a\x00\x00\x00\x00\x00\x01\x00\x02\x8f\xb3\
+\x00\x00\x02\x3a\x00\x00\x00\x00\x00\x01\x00\x02\x90\x0b\
 \x00\x00\x01\x9c\xc0\x4e\x25\x93\
-\x00\x00\x02\x4e\x00\x00\x00\x00\x00\x01\x00\x02\x9a\xb2\
+\x00\x00\x02\x4e\x00\x00\x00\x00\x00\x01\x00\x02\x9b\x0a\
 \x00\x00\x01\x9c\xc0\x4e\x25\x93\
-\x00\x00\x02\x6a\x00\x00\x00\x00\x00\x01\x00\x02\xab\x2b\
-\x00\x00\x01\x9d\x27\x67\x05\xcb\
-\x00\x00\x02\x7e\x00\x00\x00\x00\x00\x01\x00\x02\xb9\xb8\
+\x00\x00\x02\x6a\x00\x00\x00\x00\x00\x01\x00\x02\xab\x83\
+\x00\x00\x01\x9d\x2a\x26\x8b\xb5\
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 \x00\x00\x01\x9c\xc0\x4e\x25\x93\
 "
 
diff --git a/libs/shape.py b/libs/shape.py
index 07906f6..e32f1b2 100644
--- a/libs/shape.py
+++ b/libs/shape.py
@@ -104,14 +104,12 @@ def rotatePoint(self, p, theta):
         return pRes
 
     def close(self):
-        try:
-            self.center = QPointF(
-                (self.points[0].x() + self.points[2].x()) / 2,
-                (self.points[0].y() + self.points[2].y()) / 2,
-            )
-        except Exception:
+        if self.points:
+            x = sum(p.x() for p in self.points) / len(self.points)
+            y = sum(p.y() for p in self.points) / len(self.points)
+            self.center = QPointF(x, y)
+        else:
             self.center = None
-            logger.warning("The XY coordinates of QPointF are not detectable!")
         self._closed = True
 
     def reachMaxPoints(self):
diff --git a/libs/utils.py b/libs/utils.py
index 7847302..467c5dd 100644
--- a/libs/utils.py
+++ b/libs/utils.py
@@ -322,6 +322,7 @@ def keysInfo(lang="en"):
             "Ctrl + R\t\t重新识别所选标记\n"
             "Ctrl + C\t\t复制并粘贴选中的标记框\n"
             "Ctrl + B\t\t重新排序坐标框位置\n"
+            "Ctrl + T\t\t将多边形框转换为矩形框\n"
             "Ctrl + 鼠标左键\t\t多选标记框\n"
             "Backspace 或 Delete\t\t删除所选框\n"
             "Ctrl + V 或 End\t\t确认本张图片标记\n"
@@ -350,6 +351,7 @@ def keysInfo(lang="en"):
             "Ctrl + R\t\tRe-recognize the selected box\n"
             "Ctrl + C\t\tCopy and paste the selected\n"
             "Ctrl + B\t\tResort the position of bounding boxes\n"
+            "Ctrl + T\t\tConvert PolygonBox to RectBox\n"
             "\t\t\tbox\n"
             "\n"
             "Ctrl + Left Mouse\tMulti select the label\n"
diff --git a/resources/strings/strings-en.properties b/resources/strings/strings-en.properties
index 25f65a0..87627ab 100644
--- a/resources/strings/strings-en.properties
+++ b/resources/strings/strings-en.properties
@@ -124,4 +124,6 @@ resortposition=Resort position
 resortpositiondetail=Resort the bounding box positions
 settings=Settings
 settingsDetail=Application settings
-fontSize=Font Size
\ No newline at end of file
+fontSize=Font Size
+convertToRect=Convert to RectBox
+convertToRectDetail=Convert PolygonBox to RectBox
diff --git a/resources/strings/strings-zh-CN.properties b/resources/strings/strings-zh-CN.properties
index 73593b7..ef7dd63 100644
--- a/resources/strings/strings-zh-CN.properties
+++ b/resources/strings/strings-zh-CN.properties
@@ -124,4 +124,6 @@ resortposition=重新排序位置
 resortpositiondetail=重新排序坐标框位置
 settings=设置
 settingsDetail=应用程序设置
-fontSize=字体大小
\ No newline at end of file
+fontSize=字体大小
+convertToRect=转换为矩形框
+convertToRectDetail=将多边形框转换为矩形框