M4V (MPEG-4 Video — Apple/iTunes)
M4V is Apple's video file extension for MPEG-4 video, closely related to MP4. It is primarily used by iTunes and Apple TV for purchased and rented video content. M4V files may include Apple's FairPlay DRM, which restricts playback to authorized Apple devices.
MIME Type
video/x-m4v
Type
Binary
Compression
Lossless
Advantages
- + Full feature parity with MP4 (when DRM-free)
- + Supports H.264 video, AAC and AC-3 audio, subtitles
- + Native in Apple TV, iTunes, and all Apple devices
Disadvantages
- − DRM-protected M4V files only play on authorized Apple devices
- − Less universally recognized than .mp4 extension
- − Essentially MP4 with an Apple-specific extension
When to Use .M4V
M4V is primarily for iTunes content; for general use, rename DRM-free .m4v to .mp4 or use MP4 directly.
Technical Details
M4V files use the same ISOBMFF container as MP4 with H.264 video and AAC audio. Apple adds optional FairPlay DRM encryption and AC-3 audio tracks. Without DRM, an M4V file is functionally identical to an MP4 file.
History
Apple adopted the .m4v extension to distinguish iTunes video content from generic .mp4 files. The iTunes Store launched video sales in 2005, using .m4v with optional FairPlay DRM protection.