[doc] add docs about copy_xx()

docs/Tutorial-cn.md

@@ -81,6 +81,10 @@ class Image:
     def clear_icc       (self)
     def clear_thumbnail (self)
 
+    def copy_to_another_image(self, another_image,
+                              exif=True, iptc=True, xmp=True,
+                              comment=True, icc=True, thumbnail=True)
+
 
 class ImageData(Image):
     def __init__(self, data: bytes)
@@ -96,11 +100,11 @@ def convert_iptc_to_xmp(data: dict, encoding='utf-8') -> dict
 def convert_xmp_to_exif(data: dict, encoding='utf-8') -> dict
 def convert_xmp_to_iptc(data: dict, encoding='utf-8') -> dict
 
-__version__ = '...'
-__exiv2_version__ = '...'
+__version__ = '2.11.0'
+__exiv2_version__ = '0.28.1'
 ```
 
-## Class Image
+## class Image
 
 - 类 `Image` 用于根据文件路径打开图片。例如：
     ```py
@@ -118,7 +122,7 @@ __exiv2_version__ = '...'
     ```
   - 另一个例子：中国地区的 Windows 电脑通常用 GBK 编码文件路径，因此它们不能被 utf-8 解码。
 
-### close
+### close()
 
 - 当你处理完图片之后，请记得调用 `img.close()` ，以释放用于存储图片数据的内存。
   - 不调用该方法会导致内存泄漏，但不会锁定文件描述符。
@@ -128,7 +132,7 @@ __exiv2_version__ = '...'
         data = img.read_exif()
     ```
 
-### read
+### read_xx()
 
 - 读取元数据的示例:
     ```py
@@ -144,7 +148,7 @@ __exiv2_version__ = '...'
 - 调用 `Image.read_*()` 是安全的。这些方法永远不会影响图片文件（md5不变）。
 - 读取 XMP 元数据时，空白字符 `\v` 和 `\f` 会被替换为空格 ` ` 。
 
-### modify
+### modify_xx()
 
 - 修改元数据的示例:
     ```py
@@ -189,7 +193,7 @@ __exiv2_version__ = '...'
     ''
     ```
 
-### clear
+### clear_xx()
 
 - 调用 `img.clear_exif()` 将删除图片的所有 EXIF 元数据。一旦清除元数据，pyexiv2 可能无法完全恢复它。
 - `img.clear_iptc()` 和 `img.clear_xmp()` 的用法同理。
@@ -229,6 +233,30 @@ __exiv2_version__ = '...'
 - EXIF 标准允许在 JPEG 图片中嵌入缩略图，通常存储在 APP1 标签（FFE1）中。
 - Exiv2 支持读写图像中的 EXIF 缩略图。但是只能插入 JPEG 缩略图（不能插入TIFF）。
 
+### copy_xx()
+
+- 以下代码用于从一个图片拷贝元数据到另一个图片：
+  ```py
+  with pyexiv2.Image(r'.\pyexiv2\tests\1.jpg') as img1:
+      with pyexiv2.Image(r'.\pyexiv2\tests\2.jpg') as img2:
+          img2.modify_exif(img1.read_exif())
+          img2.modify_iptc(img1.read_iptc())
+          img2.modify_xmp(img1.read_xmp())
+  ```
+  但更推荐以下代码：
+  ```py
+  with pyexiv2.Image(r'.\pyexiv2\tests\1.jpg') as img1:
+      with pyexiv2.Image(r'.\pyexiv2\tests\2.jpg') as img2:
+          # 如果不想保留第二张图像中已有的元数据，可以提前清除第二张图像
+          # img2.clear_exif()
+          # img2.clear_iptc()
+          # img2.clear_xmp()
+          img1.copy_to_another_image(img2, exif=True, iptc=True, xmp=True, comment=False, icc=False, thumbnail=False)
+  ```
+  理由如下：
+  - 它的效率更高，因为不需要多次执行 modify_xx() 。
+  - 一张图片的元数据可能是错误的格式，无法被 pyexiv2 解析，但仍然可以复制到另一张图片上。
+
 ## class ImageData
 
 - 类 `ImageData` 继承于类 `Image`, 用于从字节数据中打开图片。

docs/Tutorial.md

@@ -81,6 +81,10 @@ class Image:
     def clear_icc       (self)
     def clear_thumbnail (self)
 
+    def copy_to_another_image(self, another_image,
+                              exif=True, iptc=True, xmp=True,
+                              comment=True, icc=True, thumbnail=True)
+
 
 class ImageData(Image):
     def __init__(self, data: bytes)
@@ -96,8 +100,8 @@ def convert_iptc_to_xmp(data: dict, encoding='utf-8') -> dict
 def convert_xmp_to_exif(data: dict, encoding='utf-8') -> dict
 def convert_xmp_to_iptc(data: dict, encoding='utf-8') -> dict
 
-__version__ = '...'
-__exiv2_version__ = '...'
+__version__ = '2.11.0'
+__exiv2_version__ = '0.28.1'
 ```
 
 ## class Image
@@ -118,7 +122,7 @@ __exiv2_version__ = '...'
     ```
   - Another example: Windows computers in China usually encoded file paths by GBK, so they cannot be decoded by utf-8.
 
-### close
+### close()
 
 - When you're done with the image, remember to call `img.close()` to free the memory for storing image data.
     - Not calling this method causes a memory leak, but it doesn't lock the file descriptor.
@@ -128,7 +132,7 @@ __exiv2_version__ = '...'
         data = img.read_exif()
     ```
 
-### read
+### read_xx()
 
 - An example of reading metadata:
     ```py
@@ -144,7 +148,7 @@ __exiv2_version__ = '...'
 - It is safe to call `Image.read_*()`. These methods never affect image files (md5 unchanged).
 - When reading XMP metadata, the whitespace characters `\v` and `\f` are replaced with the space ` `.
 
-### modify
+### modify_xx()
 
 - An example of modifing metadata:
     ```py
@@ -189,7 +193,7 @@ __exiv2_version__ = '...'
     ''
     ```
 
-### clear
+### clear_xx()
 
 - Calling `img.clear_exif()` will delete all EXIF metadata of the image. Once cleared, pyexiv2 may not be able to recover it completely.
 - Use `img.clear_iptc()` and `img.clear_xmp()` in the similar way.
@@ -229,6 +233,30 @@ __exiv2_version__ = '...'
 - The EXIF standard allows embedding thumbnails in a JPEG image, which is typically stored in the APP1 tag (FFE1).
 - Exiv2 supports reading and writing EXIF thumbnails in images. But only JPEG thumbnails can be inserted (not TIFF thumbnails).
 
+### copy_xx()
+
+- The following code is used to copy metadata from one image to another image:
+  ```py
+  with pyexiv2.Image(r'.\pyexiv2\tests\1.jpg') as img1:
+      with pyexiv2.Image(r'.\pyexiv2\tests\2.jpg') as img2:
+          img2.modify_exif(img1.read_exif())
+          img2.modify_iptc(img1.read_iptc())
+          img2.modify_xmp(img1.read_xmp())
+  ```
+  However, the following code is more recommended:
+  ```py
+  with pyexiv2.Image(r'.\pyexiv2\tests\1.jpg') as img1:
+      with pyexiv2.Image(r'.\pyexiv2\tests\2.jpg') as img2:
+          # If you don't want to keep the metadata already in the second image, you can clear the second image in advance.
+          # img2.clear_exif()
+          # img2.clear_iptc()
+          # img2.clear_xmp()
+          img1.copy_to_another_image(img2, exif=True, iptc=True, xmp=True, comment=False, icc=False, thumbnail=False)
+  ```
+  The reasons are as follows:
+  - It's more efficient because it doesn't require multiple executions of modify_xx() .
+  - The metadata of an image may be in the wrong format and cannot be parsed by pyexiv2, but it can still be copied to another image.
+
 ## class ImageData
 
 - Class `ImageData`, inherited from class `Image`, is used to open an image from bytes data.