修复了DCT压缩的int8导致的精度损失问题

# modified:   dctCompressImage.jpg
	modified:   main_windows/ui_main_window.py
	modified:   sub_windows/sub_window_6.py

main_windows/ui_main_window.py

@@ -61,8 +61,8 @@ class Ui_Form(object):
 
     def retranslateUi(self, Form):
         _translate = QtCore.QCoreApplication.translate
-        Form.setWindowTitle(_translate("Form", "图像处理仿真系统"))
-        self.label.setText(_translate("Form", "图像处理仿真系统"))
+        Form.setWindowTitle(_translate("Form", "数字图像处理系统"))
+        self.label.setText(_translate("Form", "数字图像处理系统"))
         self.groupBox.setTitle(_translate("Form", "图像变换"))
         self.pushButton_1.setText(_translate("Form", "色彩空间转换"))
         self.pushButton_2.setText(_translate("Form", "图像缩放剪裁"))

sub_windows/sub_window_6.py

@@ -220,6 +220,7 @@ class SubWindow(QMainWindow):
                         x_offset * block : x_offset * block + block,
                         c,
                     ] = subImg
+        retImage = np.clip(retImage, 0, 255)
         retImage = cv2.cvtColor(np.uint8(retImage), cv2.COLOR_YUV2BGR)
         retImage = retImage[0 : srcImage.shape[0], 0 : srcImage.shape[1]]
         return retImage
@@ -228,7 +229,7 @@ class SubWindow(QMainWindow):
         if self.saveImage is None:
             return
         jpg_image = cv2.imencode(".jpg", self.saveImage)[1]
-        fp = open(".././dctCompressImage.jpg", "wb")
+        fp = open("dctCompressImage.jpg", "wb")
         fp.write(jpg_image)
         fp.close()
         print("ok")