MP4 Parser & Viewer

Experimental MP4 parser/viewer for learning purpose.

Intro

• It is originated from Apple QuickTime File Format (.mov);
• then it extended to MP4;
• then it generalized into ISOBMFF, which is the basis of 3GP, JPEG 2000 as well.

QuickTime File Format
    --> ISOBMFF
        --> MP4/3GP

Atom/Box

https://developer.apple.com/documentation/quicktime-file-format/atoms

Basic structure

some.mp4
├───ftyp -------------------> FileType
├───mdat -------------------> Media Data
├───moov -------------------> Movie
│   ├───mvhd ---------------> Movie Header
│   ├───trak ---------------> Track/Stream
│   │   ├─── tkhd ----------> Track Header
│   │   └─── mdia ----------> Media Info
│   │        └─── ...
│   └───trak
│   │   ├─── tkhd ---------->
│   │   └─── mdia ---------->
│   │        └─── ...
└───udta -------------------> Userdata Box

Refs

• https://dev.to/alfg/a-quick-dive-into-mp4-57fo
• https://alfg.dev/mp4-inspector/
• https://github.com/mshafiee/mp4