Update installation steps and specify opencv version
diff --git a/PPOCRLabel/Makefile b/PPOCRLabel/Makefile
new file mode 100644
index 0000000000..7d72a890cb
--- /dev/null
+++ b/PPOCRLabel/Makefile
@@ -0,0 +1,35 @@
+# ex: set ts=8 noet:
+
+all: qt5 test
+
+test: testpy3
+
+testpy2:
+	python -m unittest discover tests
+
+testpy3:
+	python3 -m unittest discover tests
+
+qt4: qt4py2
+
+qt5: qt5py3
+
+qt4py2:
+	pyrcc4 -py2 -o libs/resources.py resources.qrc
+
+qt4py3:
+	pyrcc4 -py3 -o libs/resources.py resources.qrc
+
+qt5py3:
+	pyrcc5 -o libs/resources.py resources.qrc
+
+clean:
+	rm -rf ~/.labelImgSettings.pkl *.pyc dist labelImg.egg-info __pycache__ build
+
+pip_upload:
+	python3 setup.py upload
+
+long_description:
+	restview --long-description
+
+.PHONY: all
diff --git a/PPOCRLabel/README.md b/PPOCRLabel/README.md
index 93fd64ffe1..1b46e41276 100644
--- a/PPOCRLabel/README.md
+++ b/PPOCRLabel/README.md
@@ -24,11 +24,9 @@ python PPOCRLabel.py
 #### Ubuntu Linux
 
 ```
-sudo apt-get install pyqt5-dev-tools
-sudo apt-get install trash-cli
+pip3 install pyqt5
+pip3 install trash-cli
 cd ./PPOCRLabel # 将目录切换到PPOCRLabel文件夹下
-sudo pip3 install -r requirements/requirements-linux-python3.txt
-make qt5py3
 python3 PPOCRLabel.py
 ```
 
@@ -38,7 +36,6 @@ pip3 install pyqt5
 pip3 uninstall opencv-python # 由于mac版本的opencv与pyqt有冲突，需先手动卸载opencv
 pip3 install opencv-contrib-python-headless # 安装headless版本的open-cv
 cd ./PPOCRLabel # 将目录切换到PPOCRLabel文件夹下
-make qt5py3
 python3 PPOCRLabel.py
 ```
 
@@ -75,6 +72,20 @@ python3 PPOCRLabel.py
 |  rec_gt.txt   | 识别标签。可直接用于PPOCR识别模型训练。需用户手动点击菜单栏“PaddleOCR” - "保存识别结果"后产生。 |
 |   crop_img    |   识别数据。按照检测框切割后的图片。与rec_gt.txt同时产生。   |
 
+## 说明
+### 内置模型
+ - 默认模型：PPOCRLabel默认使用PaddleOCR中的中英文超轻量OCR模型，支持中英文与数字识别，多种语言检测。
+ - 模型语言切换：用户可通过菜单栏中 "PaddleOCR" - "选择模型" 切换内置模型语言，目前支持的语言包括法文、德文、韩文、日文。具体模型下载链接可参考[PaddleOCR模型列表](https://github.com/PaddlePaddle/PaddleOCR/blob/develop/doc/doc_ch/models_list.md).
+ - 自定义模型：用户可根据[自定义模型代码使用](https://github.com/PaddlePaddle/PaddleOCR/blob/develop/doc/doc_ch/whl.md#%E8%87%AA%E5%AE%9A%E4%B9%89%E6%A8%A1%E5%9E%8B)，通过修改PPOCRLabel.py中针对[PaddleOCR类的实例化](https://github.com/PaddlePaddle/PaddleOCR/blob/develop/PPOCRLabel/PPOCRLabel.py#L110)替换成自己训练的模型
+
+### 错误提示
+- 如果同时使用whl包安装了paddleocr，其优先级大于通过paddleocr.py调用PaddleOCR类，whl包未更新时会导致程序异常。
+- PPOCRLabel**不支持对中文文件名**的图片进行自动标注。
+- 如果您在打开软件过程中出现**objc[XXXXX]**开头的错误，证明您的opencv版本太高，建议安装4.2版本：
+```
+pip install opencv-python==4.2.0.32
+```
+
 ### 参考资料
 
 1.[Tzutalin. LabelImg. Git code (2015)](https://github.com/tzutalin/labelImg)
diff --git a/PPOCRLabel/README_en.md b/PPOCRLabel/README_en.md
index 7ebbb97c1f..d503dd3d39 100644
--- a/PPOCRLabel/README_en.md
+++ b/PPOCRLabel/README_en.md
@@ -26,11 +26,9 @@ python PPOCRLabel.py --lang en
 #### Ubuntu Linux
 
 ```
-sudo apt-get install pyqt5-dev-tools
-sudo apt-get install trash-cli
+pip3 install pyqt5
+pip3 install trash-cli
 cd ./PPOCRLabel # Change the directory to the PPOCRLabel folder
-sudo pip3 install -r requirements/requirements-linux-python3.txt
-make qt5py3
 python3 PPOCRLabel.py --lang en
 ```
 
@@ -40,7 +38,6 @@ pip3 install pyqt5
 pip3 uninstall opencv-python # Uninstall opencv manually as it conflicts with pyqt
 pip3 install opencv-contrib-python-headless # Install the headless version of opencv
 cd ./PPOCRLabel # Change the directory to the PPOCRLabel folder
-make qt5py3
 python3 PPOCRLabel.py --lang en
 ```
 
@@ -92,6 +89,14 @@ Therefore, if the recognition result has been manually changed before, it may ch
 |  rec_gt.txt   | The recognition label file, which can be directly used for PPOCR identification model training, is generated after the user clicks on the menu bar "PaddleOCR"-"Save recognition result". |
 |   crop_img    | The recognition data, generated at the same time with *rec_gt.txt* |
 
+
+### Built-in Model
+- Default model: PPOCRLabel uses the Chinese and English ultra-lightweight OCR model in PaddleOCR by default, supports Chinese, English and number recognition, and multiple language detection.
+- Model language switching: Changing the built-in model language is supportable by clicking "PaddleOCR"-"Choose OCR Model" in the menu bar. Currently supported languages​include French, German, Korean, and Japanese. 
+For specific model download links, please refer to [PaddleOCR Model List](https://github.com/PaddlePaddle/PaddleOCR/blob/develop/doc/doc_en/models_list_en.md#multilingual-recognition-modelupdating)
+- Custom model: The model trained by users can be replaced by modifying PPOCRLabel.py in [PaddleOCR class instantiation](https://github.com/PaddlePaddle/PaddleOCR/blob/develop/PPOCRLabel/PPOCRLabel.py#L110) referring [Custom Model Code](https://github.com/PaddlePaddle/PaddleOCR/blob/develop/doc/doc_en/whl_en.md#use-custom-model)
+
+
 ## Related
 
 1.[Tzutalin. LabelImg. Git code (2015)](https://github.com/tzutalin/labelImg)
diff --git a/requirements.txt b/requirements.txt
index aa1b6db4c2..4d9e8650f5 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,4 +4,4 @@ pyclipper
 lmdb
 tqdm
 numpy
-opencv-python
+opencv-python==4.2.0.32

As the new version of OpenCV(4.4.X) has conflicts with PYQT, the version of OpenCV needs to be specified.