update pgnet.md

doc/doc_ch/pgnet.md

@@ -97,7 +97,7 @@ train.txt标注文件格式如下，文件名和标注信息中间用"\t"分隔
 " 图像文件名                    json.dumps编码的图像标注信息"
 rgb/img11.jpg    [{"transcription": "ASRAMA", "points": [[214.0, 325.0], [235.0, 308.0], [259.0, 296.0], [286.0, 291.0], [313.0, 295.0], [338.0, 305.0], [362.0, 320.0], [349.0, 347.0], [330.0, 337.0], [310.0, 329.0], [290.0, 324.0], [269.0, 328.0], [249.0, 336.0], [231.0, 346.0]]}, {...}]
 ```
-json.dumps编码前的图像标注信息是包含多个字典的list，字典中的 `points` 表示文本框的14点坐标(x, y)，从左上角的点开始顺时针排列。
+json.dumps编码前的图像标注信息是包含多个字典的list，字典中的 `points` 表示文本框的多点坐标（如：4点、8点以及14点等），从左上角的点开始顺时针排列。
 `transcription` 表示当前文本框的文字，**当其内容为“###”时，表示该文本框无效，在训练时会跳过。**
 如果您想在其他数据集上训练，可以按照上述形式构建标注文件。
 

doc/doc_en/pgnet_en.md

@@ -92,7 +92,7 @@ rgb/img11.jpg    [{"transcription": "ASRAMA", "points": [[214.0, 325.0], [235.0,
 ```
 The image annotation after **json.dumps()** encoding is a list containing multiple dictionaries.
 
-The `points` in the dictionary represent the coordinates (x, y) of the 14-points of the text box, arranged clockwise from the point at the upper left corner.
+The `points` in the dictionary represent the multi-point coordinates (such as: 4 points, 8 points and 14 points, etc.) of the text box, arranged clockwise from the point at the upper left corner.
 
 `transcription` represents the text of the current text box. **When its content is "###" it means that the text box is invalid and will be skipped during training.**