> For the complete documentation index, see [llms.txt](https://overleaf-pro.ayaka.space/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://overleaf-pro.ayaka.space/latex/zh-cn/wen-da/35-how-do-i-specify-the-size-of-an-image-in-latex.md).

# 如何在 LaTeX 中指定图片大小？

要在 Overleaf 文档中插入一幅图，首先你必须 [将其上传到你的项目中](/latex/zh-cn/zhi-shi-ku/088-including-images-on-overleaf.md)。假设你已经加载了 `graphicx` 包到你的文档导言区中：

```latex
\usepackage{graphicx}
```

你可以使用 `scale=...` 选项来 `\includegraphics` 命令设置为特定值：

```latex
\includegraphics[width=0.5\textwidth]{my-uploaded-figure.png}
```

## 示例

* **注意**：以下示例使用了一个图形文件（`example-image.pdf`）由 `mwe` 包提供。这些图形文件由 TeX Live 分发，因此存储在 Overleaf 的服务器上，可作为图片占位符使用，例如下面的示例。

```latex
\documentclass{article}
\usepackage{graphicx}
\begin{document}
图像的自然大小：

\vspace{3pt}
\includegraphics{example-image.pdf}

\vspace{12pt}
缩放到 50\% 的图像：

\vspace{3pt}
\includegraphics[scale=0.5]{example-image.pdf}

\vspace{12pt}
缩放到 25\% 的图像：

\vspace{3pt}
\includegraphics[scale=0.25]{example-image.pdf}
\end{document}
```

 [在 Overleaf 中打开此示例](https://www.overleaf.com/docs?engine=pdflatex\&snip_name=How+to+change+the+size+of+an+image\&snip=%5Cdocumentclass%7Barticle%7D%0A%5Cusepackage%7Bgraphicx%7D%0A%5Cbegin%7Bdocument%7D%0ANatural+size+of+the+image%3A%0A%0A%5Cvspace%7B3pt%7D%0A%5Cincludegraphics%7Bexample-image.pdf%7D%0A%0A%5Cvspace%7B12pt%7D%0AImage+scaled+to+50%5C%25%3A%0A%0A%5Cvspace%7B3pt%7D%0A%5Cincludegraphics%5Bscale%3D0.5%5D%7Bexample-image.pdf%7D%0A%0A%5Cvspace%7B12pt%7D%0AImage+scaled+to+25%5C%25%3A%0A%0A%5Cvspace%7B3pt%7D%0A%5Cincludegraphics%5Bscale%3D0.25%5D%7Bexample-image.pdf%7D%0A%5Cend%7Bdocument%7D)

此示例生成以下输出：

![如何在 LaTeX 中改变图像大小](/files/366f64c4ffa50e9f1376f7d864eff2affd288768)

在我们的默认论文模板中也有一个这样的示例——你可以通过以下方式试用它： [创建一篇新论文](https://www.overleaf.com/docs?template=paper) ，以查看图像 `frog.jpg` 是如何通过写入以下内容按文本宽度的一部分进行缩放的：

```latex
\includegraphics[width=0.3\textwidth]{frog.jpg}
```


---

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```
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