M4V 转 ALAC 转换器

A free M4V to ALAC converter for iTunes Video files. Browser-based pairs here usually run in this tab, with no file upload.

将你的 M4V 文件拖放到这里

or 浏览你的设备 · 粘贴快捷键 Ctrl+V

Accepts .m4v files. You can queue several files; each is processed one after another on your own device.

你的文件永远不会离开这台设备 —— 没有上传，也就没有服务器可以从中删除它们。

使用方法

01
添加你的 M4V 文件
将文件拖放到上方的方框里，或点击浏览选择。它们会直接从磁盘读取 —— 不会发送到任何地方。
02
检查设置
ALAC is already selected. Open the gear icon on any row if you want to change quality, dimensions or codec before converting.
03
下载你的 ALAC
点击转换，等待该行处理完成。转换多个文件时，可以将它们全部打包为一个 ZIP 一次性下载。

M4V

iTunes Video

苹果为 iTunes 使用的 MP4 变体格式，偶尔会带有 FairPlay DRM 保护。没有 DRM 保护的文件实际上等同于 MP4；这个扩展名主要是告诉苹果的软件应该如何处理它。

开发者: Apple
发布时间: 2005
扩展名: .m4v
MIME 类型: video/x-m4v
压缩方式: 有损

ALAC

Apple Lossless Audio Codec

苹果的无损编解码器，于 2011 年开源。压缩效果与 FLAC 相当，也是 iOS 和 iTunes 唯一原生支持的无损格式。

开发者: Apple
发布时间: 2004
扩展名: .alac
MIME 类型: audio/mp4
压缩方式: 无损
规范: 开放

转换前值得了解

M4V is lossy and ALAC is lossless. Re-saving cannot recover details removed by the lossy source. The output is usually larger with similar visible quality, not a repaired original.
这次转换只会保留音轨 —— 画面会被完全丢弃。

FAQ

关于 M4V 转 ALAC 的常见问题

这个 M4V 转 ALAC 转换器是免费的吗？

是的。在这里把 M4V 转换为 ALAC 完全免费，无需账号、没有水印、也没有每日次数限制。处理在你自己的设备上完成，因此不存在需要转嫁给你的服务器成本。

我的 M4V 文件会被上传到任何地方吗？

For browser-based pairs, your file is read locally and converted by ffmpeg in this tab. No file payload is uploaded; you may still see analytics and engine downloads in network logs.

M4V 转 ALAC 有文件大小限制吗？

There is no imposed upload cap when it runs in-browser, but each conversion still depends on your device and browser memory. Large videos are the first practical limit, then memory-heavy documents or images.

把 M4V 转换为 ALAC 会损失质量吗？

Nothing is intentionally discarded in this step, because ALAC is lossless. A M4V file encoded with lossy settings stays lossy, so missing detail is not recovered.

可以一次把多个 M4V 文件转换为 ALAC 吗？

Yes. Drop in several files and each gets its own row; they are processed one after another on your device. You can download them one by one or as one ZIP.

M4V 转 ALAC 能在手机、Mac 或 Chromebook 上使用吗？

Most modern browsers on Windows, macOS, Linux, ChromeOS, Android and iOS work. Very large videos are often more reliable on desktop or a browser with more memory.

Why do some conversions take longer on first run?

The conversion engine has to download first. Small codec bundles are fast, while ffmpeg is commonly 12–30 MB; later conversions of similar type use the cached engine.

I converted a file and the output is blank or unusable. What should I check?

Start over with default settings, then change one option at a time (quality, bitrate, page size, or codec) to isolate what changed behavior. If it keeps failing, retry with a smaller file and confirm the source format matches the pair.

将 M4V 转换为其他格式

一个 M4V 文件可以转换为以下任意一种格式。