BDAV is an application format usually for broadcasters, owners of TV recorders, and hobbyist. It uses DVD-like interactivity for menus. BDAV apps are usually for burning/recording on BD-Rs and BD-REs (including BD-XLs), and not used on BD-ROMs. (It's very rare for commercial BD-Rs to be published in the BDAV format). Almost Blu-ray players are compatible with BDAV Version 1.0, but other versions vary by player. It was first released in 2003, predating three years before BDMV for BD-ROMs.

Blu-ray Audio Visual Application Format (BDAV) v5.0

Blu-ray logo
Type	Application Platform
Play modes	HEVC TS, HDMV TS, SESF
Developers	Blu-ray Disc Association
Video Encoding	H.262/MPEG-2 Part 2 H.264/MPEG-4 AVC HEVC
Audio Encoding	PCM Dolby Digital MPEG-1 (SESF) MPEG2 AAC (HEVC TS) MPEG4 AAC (HEVC TS) MPEG2 ALS (HEVC TS)
Graphics	TDT Thumbnails Presentation Graphics Stream TTML Text Stream (HEVC TS) Teletex (SESF)
Programming Languages	N/A
Applications	Recording, Broadcasting, and Movies
Minimum CPU speed	N/A
Display	352×288 to 720×480 (SESF) 720×480 to 1920×1080 (HDMV TS) 1920×1080 to 7680×4320 (HEVC TS)
Local Storage	N/A
Memory	Primary Video: ? Primary Audio: ? Presentation Graphics/Text Stream: 4 MB TID Thumbnail: 4 MB? Data Cache: ?
Media	Blu-ray Disc (BD-R, BD-RE, BD-XL), Digital (ISO file)
First Release	2003 (Version 1.0)
Lastest Release	2018 (Version 5.0)

As of Version 5, BDAV, has three play modes, HDMV TS, HEVC TS, and SESF (Also supports Japan's IDSB broadcasting format). BDAV apps can be converted to BDMV apps (HDMV TS to HDMV only). BDAV interactivity is very similar to DVD, so it's not intended for video games or interactive applications..

Video & Audio Layers

An BDMV Application is divided into three layers for video, audio, and graphics. Each play mode has one video layer that can go up to 480p (SESF), 1080p (HDMV TS) and 2160p/4320p (HEVC TS)*.

HEVC TS - UHD Broadcasting/Recording

• Primary Video - HEVC video (supports native 4K and 8K resolutions)*
  
• Primary Audio - MPEG2 AAC audio, MPEG4 AAC audio, MPEG4 ALS audio
  
• Presentation Graphics Stream
• Text Stream - Timed Text Markup Language document (TTML)

HDMV TS - HD Broadcasting/Recording

• Primary Video - AVC Video
• Primary Audio - PCM Audio, Dolby Digital
  
• Presentation Graphics Stream

SESF (Self-Encoded Stream Format) - Analog SD Broadcasting/Recording

• Primary Video - MPEG2 Video
  
• Primary Audio - PCM Audio, Dolby Digital, MPEG-1
  
• Teletext Stream (supported for PAL)
• Tip data - Tip TS

File Directory

BD-Rs/BD-REs uses the Universal Disk Format (UDF) 2.50 and 2.60 developed by the Optical Storage Technology Association (OSTA), an open, vendor-neutral file system for data storage for optical discs, and it's a compatible-friendly format for both Personal Computers and consumer electronics environments. Similar to BDMV, a BDAV application has a standard hierarchical file structure of mandatory and optional file directories and sub-directories:

1. BDAV directory: contains mandatory files and the PLAYLIST, CLIPINF, and STREAM directories.
   
   • index.bdav file: stores information describing the contents of the BDAV directory. There is only one index.bdmv file under the BDAV directory.
   • menu.tidx file: menu thumbnail index
   • menu.tdt1, menu.tdt2, etc.: menu thumbnail (based on the JPEG image format)
     
   • mark.tidx: mark thumbnail index
   • mark.tdt1, mark.tdt2, etc.: mark thumbnail (based on the JPEG image format)
   • PLAYLIST directory: contains the Database files for Movie PlayLists.
     • xxxxx.rpls files: store information corresponding to Movie PlayLists. One file is created for each Movie PlayList. The filenames of these files are in the form "xxxxx.rpls", where "xxxxx" is a 5-digit number corresponding to the Movie PlayList. 
     • xxxxx.vpls files: The filenames of these files are in the form "xxxxx.vpls", where "xxxxx" is a 5-digit number corresponding to the Movie PlayList.
   • CLIPINF directory: contains the Database files for Clips.
     • zzzzz.clpi files: store Clip information associated with a Clip AV stream file. The filenames of these files are in the form "zzzzz.clpi", where "zzzzz" is a 5-digit number corresponding to the Clip.
   • STREAM directory: contains AV stream files.
     • zzzzz.m2ts file: contains a BDAV MPEG-2 transport stream. The names of these files are in the form "zzzzz.m2ts", where "zzzzz" is a 5-digit number corresponding to the Clip. The same 5-digit number "zzzzz" is used for an AV stream file and its associated Clip information file.
     • zzzzz.dvsd file: The names of these files are in the form "zzzzz.dvsd", where "zzzzz" is a 5-digit number corresponding to the Clip. The same 5-digit number "zzzzz" is used for an AV stream file and its associated Clip information file.