update zh-cn/application-dev/media/image-pixelmap-operation.md.

Signed-off-by: N刘关鹏 <liuguanpeng1@huawei.com>

zh-cn/application-dev/media/image-pixelmap-operation.md

@@ -27,6 +27,7 @@
 3. 读取并修改目标区域像素数据，写回原图。
      
    ```ts
+   import {BusinessError} from '@ohos.base'
    // 场景一：将读取的整张图像像素数据结果写入ArrayBuffer中
    const readBuffer = new ArrayBuffer(pixelBytesNumber);
    pixelMap.readPixelsToBuffer(readBuffer).then(() => {