ICO（Windows 图标格式）
ICO 是一种容器格式，用于 Microsoft Windows 上的图标和网站收藏夹图标（favicon）。单个 ICO 文件可以包含不同大小和色深的多个图像。它仍然是浏览器标签页图标（favicon）的标准格式，与 PNG 并列。
MIME 类型
image/vnd.microsoft.icon
类型
二进制
压缩
无损
优点
- + Multiple sizes in a single file
- + Universal favicon support across browsers
- + Transparent background support
缺点
- − Limited to icon use cases
- − Maximum practical size of 256x256 pixels
- − Windows-centric format
何时使用 .ICO
适用于 Windows 应用程序图标和网站收藏夹图标。建议在单个文件中包含多个尺寸（16x16、32x32、48x48）以获得最佳显示效果。
技术细节
ICO 文件包含多种尺寸（16x16、32x32、48x48、256x256）的 BMP 或 PNG 图像目录。现代 ICO 文件通常对 48x48 以上的尺寸使用 PNG 压缩嵌入。
历史
ICO 于 1985 年随 Windows 1.0 一起推出，用于桌面应用程序图标。1999 年 Internet Explorer 5 支持 favicon.ico 后，它成为了网页收藏夹图标的标准。
从 .ICO 转换
转换为 .ICO
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