🎬 MOV 转 MP4（无损转换）MOV to MP4 Converter

使用说明与常见问题How-to & FAQ

「MOV 转 MP4（无损转换）」是什么？What is the MOV to MP4 Converter tool?

把 iPhone、相机或 QuickTime 的 MOV 视频转成 MP4：H.264/HEVC + AAC 的文件直接无损转封装，几秒完成且画质不变，可选“快速启动”让网页和手机边下边播；ProRes 等不兼容编码会提示并可改为重新编码。Convert MOV videos from iPhones, cameras or QuickTime to MP4. H.264/HEVC + AAC files are remuxed losslessly in seconds with identical quality, with optional fast start for streaming on the web and phones; incompatible codecs such as ProRes are flagged, with a re-encode option.

如何使用「MOV 转 MP4（无损转换）」？How do I use the MOV to MP4 Converter tool?

在「MOV 转 MP4（无损转换）」中，点击「无损转换为 MP4」、「重新编码（较慢）」、「停止」按钮即可。支持拖放文件。In the MOV to MP4 Converter: Click "Convert to MP4 (lossless)", "Re-encode (slow)", "Stop". Drag-and-drop files is supported.

为什么转换只要几秒？画质会变差吗？Why does it take only seconds? Is quality lost?

MOV 和 MP4 都基于同一种文件结构（ISO 基础媒体格式）。如果视频是 H.264 或 HEVC、音频是 AAC（iPhone 和大多数相机都是），只需要改写文件头和索引，视频数据原样复制，所以几秒就能完成，画质、帧率和音质完全不变。MOV and MP4 share the same underlying structure (ISO base media format). When the video is H.264 or HEVC and the audio AAC — as on iPhones and most cameras — only the header and index are rewritten while the media data is copied as-is, so it takes seconds and picture, frame rate and sound are unchanged.

“快速启动”是什么？What is fast start?

很多相机把索引（moov）写在文件末尾，网页或手机播放时必须先下载完整文件。勾选后索引会移到开头，在线播放可以立即开始。Many cameras write the index (moov) at the end of the file, so web and phone players must download everything before playing. With fast start the index moves to the front and streaming playback starts immediately.

iPhone 的 HEVC 视频转换后能在 Windows 上播放吗？Will iPhone HEVC videos play on Windows after conversion?

转换后的 MP4 仍然是 HEVC 编码。Windows 自带播放器需要安装 HEVC 扩展，旧电脑或部分网站可能无法播放；这种情况可以使用“重新编码”，在支持的浏览器中输出 H.264 MP4（耗时约等于视频时长，画质会有轻微损失）。重新编码的音频在 Windows/macOS 版 Chrome、Edge 和 Safari 中为 AAC；Linux 版 Chrome 和 Firefox 只能录制 Opus 音频，结果里会明确注明（QuickTime 和旧款 iPhone 可能播放不出声音）。The MP4 is still HEVC. Windows' built-in player needs the HEVC extension, and older PCs or some websites may not play it. In that case use Re-encode, which outputs H.264 MP4 in supporting browsers (takes about as long as the video, with slight quality loss). Re-encoded audio is AAC in Chrome, Edge and Safari on Windows/macOS; Chrome on Linux and Firefox can only record Opus audio, which the result states clearly (QuickTime and older iPhones may play it without sound).

哪些 MOV 不能无损转换？Which MOVs can't be converted losslessly?

ProRes、Motion JPEG、DV、未压缩 PCM 音频等专业编码不能放进标准 MP4，工具会列出具体编码。可以尝试“重新编码”，但浏览器通常也无法播放 ProRes，这时需要用桌面软件转换。ProRes, Motion JPEG, DV, uncompressed PCM audio and other professional codecs can't go into a standard MP4; the tool names the codec. You can try Re-encode, but browsers usually can't play ProRes either — desktop software is needed then.

视频会上传到服务器吗？Is my video uploaded?

不会。所有处理都在你的浏览器里完成，文件不会离开你的设备，所以也不受上传大小和网速限制（但受电脑内存和性能限制）。No. Everything runs in your browser and the file never leaves your device, so there are no upload limits or waits — only your computer's memory and speed.

「MOV 转 MP4（无损转换）」免费吗？需要注册吗？Is the MOV to MP4 Converter free? Do I need an account?

「MOV 转 MP4（无损转换）」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 MOV to MP4 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.