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Co-authored-by: Jason <jiangjiajun@baidu.com>
Co-authored-by: heliqi <1101791222@qq.com>

examples/vision/ocr/PP-OCRv2/serving/README.md

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+# PP-OCRv2服务化部署示例
+
+除了`下载的模型`和`rec前处理的1个参数`以外PP-OCRv2的服务化部署与PP-OCRv3服务化部署全部一样，请参考[PP-OCRv3服务化部署](../../PP-OCRv3/serving)。
+
+## 下载模型
+将下载链接中的`v3`改为`v2`即可。
+
+## 修改rec前处理参数
+在[model.py](../../PP-OCRv3/serving/models/det_postprocess/1/model.py#L109)文件**109行添加以下代码**：
+```
+self.rec_preprocessor.cls_image_shape[1] = 32
+```