fix readme (#30)

README.md

@@ -6,8 +6,8 @@ Note:
 - Model source:
     - `text_recognition_CRNN_EN_2021sep.onnx`: https://docs.opencv.org/4.5.2/d9/d1e/tutorial_dnn_OCR.html (CRNN_VGG_BiLSTM_CTC.onnx)
     - `text_recognition_CRNN_CN_2021nov.onnx`: https://docs.opencv.org/4.5.2/d4/d43/tutorial_dnn_text_spotting.html (crnn_cs_CN.onnx)
-- `text_recognition_CRNN_EN_2021sep.onnx` can detect digits (0~9) and letters (return lowercase letters a~z) (view `charset_36_EN.txt` for details).
-- `text_recognition_CRNN_CN_2021nov.onnx` can detect digits (0~9), upper/lower-case letters (a~z and A~Z), some Chinese characters and some special characters (view `charset_3944_CN.txt` for details).
+- `text_recognition_CRNN_EN_2021sep.onnx` can detect digits (0\~9) and letters (return lowercase letters a\~z) (view `charset_36_EN.txt` for details).
+- `text_recognition_CRNN_CN_2021nov.onnx` can detect digits (0\~9), upper/lower-case letters (a\~z and A\~Z), some Chinese characters and some special characters (view `charset_3944_CN.txt` for details).
 - For details on training this model series, please visit https://github.com/zihaomu/deep-text-recognition-benchmark.
 
 ## Demo
@@ -44,4 +44,4 @@ All files in this directory are licensed under [Apache 2.0 License](./LICENSE).
 - https://github.com/bgshih/crnn
 - https://github.com/meijieru/crnn.pytorch
 - https://github.com/zihaomu/deep-text-recognition-benchmark
-- https://docs.opencv.org/4.5.2/d9/d1e/tutorial_dnn_OCR.html
+- https://docs.opencv.org/4.5.2/d9/d1e/tutorial_dnn_OCR.html