NXV

2007-01-15T14:35:52Z

MagicalTux:

* Extension: nxv
* Samples: tbd

NXV is a container format used by the "Brando MP4 Watch" product. The wrist watch is reported to support MP4, WMV and WMA, however this is achieved by first converting the files to the NXV format.

==Container Format==
bytes 0-11 ASCIIZ magic ("NXV File")
bytes 16-19 ASCIIZ version ("1.0.0", "3.0.1" or "3.0.2")
byte 20 width (pixels)
byte 21 height (pixels)
byte 22-23 unknown (little endian)
byte 24-511 rand byte
(The a/v sequence commences at byte 512.)
while eof
u8[0x7fc] audio payload
le16 length (bytes)
le16 unknown
u8[length] video payload

==Audio Payload==
The audio payload is an [[MP3]] stream, including RIFF WAVE headers.

==Video Payload==
Raw video. 16bpp in 565 RGB format. If the version is "1.0.0", the video is at full-resolution. If the version is "3.0.1", the video is at quarter-resolution. Version "3.0.2" seems to indicate a different format, but it is not yet known what that format is.

==Notes==
* Supported video resolutions are: 96x64, 96x80, 96x96, 128x96, 128x128, 160x128, 176x128. Despite the reduction in video resolution, the resulting NXV file size exceeds that of the input video file.
* Intermediate files are used by the NxvConverter program to store the audio and video payloads (filename.mp3 and filename.tmp) prior to muxing to the NXV file.
* Files generated in low and medium quality by NxvConverter have one frame per packet of video payload. Files in high quality have variable-size packets with some extra information between frames.

==External Links==
* [http://watch.brando.com.hk/prod_detail.php?prod_id=00100 Brando MP4 Watch Product Page]
* [http://forum.doom9.org/showthread.php?t=119616 Related doom9 thread]
* [http://www.nxdevice.com/ Vendor website]

[[Category:Container Formats]]

MultimediaWiki - User contributions [en]

NXV