add docs for dataformats in add_image (#803)

Co-authored-by: NPeter Pan <littlepanzh@gmail.com>

docs/components/README.md

@@ -201,7 +201,7 @@ Image 组件用于显示图片数据随训练的变化。在模型训练过程
 Image 组件的记录接口如下：
 
 ```python
-add_image(tag, img, step, walltime=None)
+add_image(tag, img, step, walltime=None, dataformats="HWC")
 ```
 接口参数说明如下：
 |   参数   |     格式      |                    含义                     |
@@ -210,6 +210,7 @@ add_image(tag, img, step, walltime=None)
 | img      | numpy.ndarray | 以ndarray格式表示的图片                     |
 | step     | int           | 记录的步数                                  |
 | walltime | int           | 记录数据的时间戳，默认为当前时间戳          |
+| dataformats| string      | 传入的图片格式，包括`NCHW`、`HWC`、`HW`，默认为`HWC`|
 
 ### Demo
 下面展示了使用 Image 组件记录数据的示例，代码文件请见[Image组件](https://github.com/PaddlePaddle/VisualDL/blob/develop/demo/components/image_test.py)

docs/components/UserGuide-en.md

@@ -203,7 +203,7 @@ The Image is used to present the change of image data during training. Developer
 The interface of the Image is shown as follows:
 
 ```python
-add_image(tag, img, step, walltime=None)
+add_image(tag, img, step, walltime=None, dataformats="HWC")
 ```
 The interface parameters are described as follows:
 | parameter | format        | meaning                                                      |
@@ -212,6 +212,7 @@ The interface parameters are described as follows:
 | img       | numpy.ndarray | Images in ndarray format                                     |
 | step      | int           | Record the training steps                                    |
 | walltime  | int           | Record the time-stamp of the data, the default is the current time-stamp |
+| dataformats| string       | Format of image，include `NCHW`、`HWC`、`HW`，default is `HWC`|
 
 ### Demo
 The following shows an example of using Image to record data, and the script can be found in [Image Demo](https://github.com/PaddlePaddle/VisualDL/blob/develop/demo/components/image_test.py).

visualdl/component/base_component.py

@@ -146,6 +146,7 @@ def image(tag, image_array, step, walltime=None, dataformats="HWC"):
         image_array (numpy.ndarray): Value of iamge
         step (int): Step of image
         walltime (int): Wall time of image
+        dataformats (string): Format of image
 
     Return:
         Package with format of record_pb2.Record

visualdl/writer/writer.py

@@ -171,6 +171,7 @@ class LogWriter(object):
             img (numpy.ndarray): Image represented by a numpy.array
             step (int): Step of image
             walltime (int): Wall time of image
+            dataformats (string): Format of image
 
         Example:
             from PIL import Image