📱 HEIC 转 AVIF（iPhone 照片）HEIC to AVIF Converter

使用说明与常见问题How-to & FAQ

「HEIC 转 AVIF（iPhone 照片）」是什么？What is the HEIC to AVIF Converter tool?

把 iPhone 的 HEIC/HEIF 照片批量转换为 AVIF：同样是高效的新格式，但浏览器和网站支持远比 HEIC 广泛，可调质量、编码速度或选择无损，多张打包 ZIP，照片只在浏览器本地解码和编码。Batch-convert iPhone HEIC/HEIF photos to AVIF — another efficient modern format, but one that browsers and websites support far more widely than HEIC — with adjustable quality, encoder speed or lossless mode. Download each file or a ZIP; photos are decoded and encoded only in your browser.

如何使用「HEIC 转 AVIF（iPhone 照片）」？How do I use the HEIC to AVIF Converter tool?

在「HEIC 转 AVIF（iPhone 照片）」中，选择或拖入文件，按需设置「质量」、「编码速度」等选项，然后点击「全部下载（ZIP）」按钮即可。In the HEIC to AVIF Converter: Choose or drop your files, set "Quality", "Encoder speed", then click "Download all (ZIP)".

HEIC 和 AVIF 有什么区别？为什么要转？How do HEIC and AVIF differ, and why convert?

两者都使用 HEIF 容器，HEIC 用 HEVC（H.265）编码，AVIF 用免版税的 AV1 编码，压缩率相近。HEVC 的专利授权让大多数浏览器不支持 HEIC，而 Chrome、Edge、Firefox 和 Safari 16+ 都能直接显示 AVIF，所以想把手机照片放到网页上、又不想换成更大的 JPG 时，转 AVIF 最合适。注意转换是重新编码，不是无损转封装。Both use the HEIF container: HEIC is encoded with HEVC (H.265) and AVIF with royalty-free AV1, with similar compression. HEVC patent licensing keeps HEIC out of most browsers, while Chrome, Edge, Firefox and Safari 16+ all display AVIF — so AVIF is the best choice for putting phone photos on the web without switching to bigger JPGs. Note that this re-encodes the photo; it is not a lossless rewrap.

HEIC 是什么？第一次为什么慢？What is HEIC, and why is the first run slow?

HEIC 是 iPhone 和不少安卓手机默认的照片格式（HEIF 容器 + HEVC 编码），Windows、网页和很多软件不能直接打开。解码组件 heic2any（MIT，内含 LGPL 许可的 libheif）约 1.3 MB，第一次转换时才加载；实况照片和连拍只取主图。少数带透明通道的 HEIC（iPhone 照片没有）目前读不出透明信息，透明区域会按不透明处理，转换后会在结果旁提示。HEIC is the default photo format on iPhones and many Android phones (HEIF container + HEVC), which Windows, websites and many apps cannot open directly. The decoder, heic2any (MIT, bundling LGPL-licensed libheif), is about 1.3 MB and loads on first use; Live Photos and bursts give the main image only. The rare HEIC files with an alpha channel (iPhone photos have none) can't have their transparency read yet, so transparent areas come out opaque; the result row says so.

AVIF 有什么好处？质量和速度怎么选？Why AVIF, and how do I set quality and speed?

AVIF 基于 AV1 视频编码，同等画质下通常比 JPG 小一半左右、也比 WebP 更小，并支持透明。质量 60 是兼顾体积和画质的常用值，80 以上肉眼几乎无损；“编码速度”越慢文件越小，但大图可能要十几秒。勾选“无损”会按 4:4:4 无损编码，像素完全不变，但文件往往比 PNG 小不了多少。AVIF is based on the AV1 video codec: at the same visual quality it is often around half the size of JPG and smaller than WebP, with transparency support. Quality 60 is a common balance of size and quality and 80+ looks lossless to most eyes; slower encoder speeds give smaller files but large images can take 10+ seconds. Lossless encodes 4:4:4 with every pixel unchanged, though the file is often not much smaller than PNG.

编码在哪里进行？第一次为什么慢？Where does encoding happen, and why is the first run slow?

浏览器的 Canvas 不能直接导出 AVIF，所以本工具在后台线程（Web Worker）中运行开源编码器 libavif + libaom（WebAssembly，来自 jSquash，Apache-2.0 / BSD 许可）。编码组件约 3.5 MB，第一次转换时下载，之后由浏览器缓存；图片始终只在本机处理，不会上传。单张最多 4,000 万像素。Browser Canvas cannot export AVIF, so the tool runs the open-source libavif + libaom encoder (WebAssembly, from jSquash, Apache-2.0 / BSD licensed) in a background Web Worker. The encoder is about 3.5 MB and downloads on first use, then stays in the browser cache; images are only processed on your device and never uploaded. Each image can be up to 40 megapixels.

图片会上传吗？Are my images uploaded?

不会。解码和编码都在你的浏览器里完成，文件不会离开你的设备；照片中的 EXIF 元数据（包括拍摄位置）不会写入输出文件。No. Decoding and encoding happen in your browser and files never leave your device; EXIF metadata in photos (including location) is not written to the output.

「HEIC 转 AVIF（iPhone 照片）」免费吗？需要注册吗？Is the HEIC to AVIF Converter free? Do I need an account?

「HEIC 转 AVIF（iPhone 照片）」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The HEIC to AVIF Converter is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.