IFO (DVD info)
Also known as: IFO file, DVD IFO, VIDEO_TS IFO, DVD information file
IFO files are the small information files on a DVD-Video disc, stored in the VIDEO_TS folder. They tell the player where chapters, menus, subtitles, and audio tracks live inside the large VOB video files.
- DVD navigation/info files in the VIDEO_TS folder
- Point to chapters, menus, audio, and subtitles in VOBs
- Usually paired with a .BUP backup file
The DVD navigation map
A DVD-Video disc keeps its actual video in VOB files, but those are just streams. The IFO files act as a table of contents and navigation map: chapter points, menu layouts, audio and subtitle track lists, and playback rules.
Each IFO usually has a matching backup (.BUP) file in case the original is damaged. You will see them alongside VOBs in the VIDEO_TS folder.
Why you rarely open IFO directly
IFO files contain no video themselves, so opening one on its own shows little. DVD player software and rippers read them automatically to present menus and chapters.
When converting a DVD to a single video file, tools use the IFO to assemble the VOBs in the right order.