Using face API with an already opened cv2 image

> Please provide us with the following information:
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How do I use azure face API with an already opened cv2 image without saving it again locally or on the web?
I tried looking for it in the documentations, but couldn't find a solution.
As far as I know and could find, there are only two ways of reading an image:
1. detect_with_url : Needs an URL to read the image.
2. detect_with_stream: Needs an image path to read the image.
### This issue is for a: (mark with an `x`)
```
- [ ] bug report -> please search issues before submitting
- [ ] feature request
- [x] documentation issue or request
- [ ] regression (a behavior that used to work and stopped in a new release)
```
### Expected/desired behavior
>

The face API should have a function or work-around to use an already opened image without having to save it.
### OS and Version?

Windows 10 and Raspberry Pi
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> Thanks! We'll be in touch soon.

首先检查 Face API 文档以及 detect_with_url 和 detect_with_stream 的快速入门示例，然后确定如何在不保存图像的情况下传入已经打开的 cv2 图像。当相关文档说明支持的输入，并在无法直接使用时提供明确的替代方案时，即可视为完成。

由索引模型根据 Issue 内容生成。