To play videos, you'll need to convert them to the Rocket Video (.rvid) format using Vid2RVID.

Features

• Support for videos up to 60FPS (compatible with even the DS & DS Lite systems)!
• Both 8 BPP (256 colors) and 16 BPP (RGB555/RGB565) videos are supported.
  • Screen color filters are not supported for 16 BPP videos.
• Support for dual-screen videos!
• Support for audio up to 32khz Mono.
• The video UI from the "Nintendo DSi + Internet" app, with the title bar now containing the console's set color.
• Console-based file browser to search for your .rvid file.

Video UI Controls

• A or touch Play/Pause button: Play/Pause video
• L shoulder or touch the left tip of the play bar: Stop video
• D-Pad Left/Right: Jump 5 seconds (30 seconds with R shoulder held)
• D-Pad Down/Up: Jump 10 seconds (1 minute with R shoulder held)
• D-Pad Left+Down/Up+Right: Jump 15 seconds (2 minutes with R shoulder held)
• SELECT: Turn off/on bottom screen backlight (only applies to single-screen videos)
• B or touch Return: Exit video

Credits

• AntonioND: BlocksDS
• Gericom: LZ77 decompressor code from EFE/EveryFileExplorer, and frame rate + play bar adjustment code from FastVideoDSPlayer.
• devkitPro: nds-hb-menu's file browsing code.