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 @settitle NUT
 
 @titlepage
 @center @titlefont{NUT}
 @end titlepage
 
 @top
 
 @contents
 
 @chapter Description
 NUT is a low overhead generic container format. It stores audio, video,
 subtitle and user-defined streams in a simple, yet efficient, way.
 
 It was created by a group of FFmpeg and MPlayer developers in 2003
 and was finalized in 2008.
 

 The official nut specification is at svn://svn.mplayerhq.hu/nut
 In case of any differences between this text and the official specification,
 the official specification shall prevail.
 

 @chapter Modes
 NUT has some variants signaled by using the flags field in its main header.
 
 @multitable @columnfractions .4 .4
 @item BROADCAST   @tab Extend the syncpoint to report the sender wallclock
 @item PIPE        @tab Omit completely the syncpoint
 @end multitable
 
 @section BROADCAST
 
 The BROADCAST variant provides a secondary time reference to facilitate
 detecting endpoint latency and network delays.

 It assumes all the endpoint clocks are synchronized.

 To be used in real-time scenarios.
 
 @section PIPE
 
 The PIPE variant assumes NUT is used as non-seekable intermediate container,
 by not using syncpoint removes unneeded overhead and reduces the overall
 memory usage.
 

 @chapter Container-specific codec tags
 
 @section Generic raw YUVA formats
 
 Since many exotic planar YUVA pixel formats are not considered by
 the AVI/QuickTime FourCC lists, the following scheme is adopted for
 representing them.
 
 The first two bytes can contain the values:
 Y1 = only Y
 Y2 = Y+A
 Y3 = YUV
 Y4 = YUVA
 
 The third byte represents the width and height chroma subsampling
 values for the UV planes, that is the amount to shift the luma
 width/height right to find the chroma width/height.
 
 The fourth byte is the number of bits used (8, 16, ...).
 
 If the order of bytes is inverted, that means that each component has
 to be read big-endian.
 
 @section Raw Audio
 
 @multitable @columnfractions .4 .4
 @item ALAW  @tab A-LAW
 @item ULAW  @tab MU-LAW
 @item P<type><interleaving><bits> @tab little-endian PCM
 @item <bits><interleaving><type>P @tab big-endian PCM
 @end multitable
 
 <type> is S for signed integer, U for unsigned integer, F for IEEE float

 <interleaving> is D for default, P is for planar.

 <bits> is 8/16/24/32
 
 @example
 PFD[32]   would for example be signed 32 bit little-endian IEEE float
 @end example
 
 @section Subtitles
 
 @multitable @columnfractions .4 .4
 @item UTF8   @tab Raw UTF-8
 @item SSA[0] @tab SubStation Alpha
 @item DVDS   @tab DVD subtitles
 @item DVBS   @tab DVB subtitles
 @end multitable
 

 @section Raw Data
 
 @multitable @columnfractions .4 .4
 @item UTF8   @tab Raw UTF-8
 @end multitable
 

 @section Codecs
 
 @multitable @columnfractions .4 .4
 @item 3IV1 @tab non-compliant MPEG-4 generated by old 3ivx
 @item ASV1 @tab Asus Video
 @item ASV2 @tab Asus Video 2
 @item CVID @tab Cinepak
 @item CYUV @tab Creative YUV
 @item DIVX @tab non-compliant MPEG-4 generated by old DivX
 @item DUCK @tab Truemotion 1
 @item FFV1 @tab FFmpeg video 1
 @item FFVH @tab FFmpeg Huffyuv
 @item H261 @tab ITU H.261
 @item H262 @tab ITU H.262
 @item H263 @tab ITU H.263
 @item H264 @tab ITU H.264
 @item HFYU @tab Huffyuv
 @item I263 @tab Intel H.263
 @item IV31 @tab Indeo 3.1
 @item IV32 @tab Indeo 3.2
 @item IV50 @tab Indeo 5.0
 @item LJPG @tab ITU JPEG (lossless)
 @item MJLS @tab ITU JPEG-LS
 @item MJPG @tab ITU JPEG
 @item MPG4 @tab MS MPEG-4v1 (not ISO MPEG-4)
 @item MP42 @tab MS MPEG-4v2
 @item MP43 @tab MS MPEG-4v3
 @item MP4V @tab ISO MPEG-4 Part 2 Video (from old encoders)
 @item mpg1 @tab ISO MPEG-1 Video
 @item mpg2 @tab ISO MPEG-2 Video
 @item MRLE @tab MS RLE
 @item MSVC @tab MS Video 1
 @item RT21 @tab Indeo 2.1
 @item RV10 @tab RealVideo 1.0
 @item RV20 @tab RealVideo 2.0
 @item RV30 @tab RealVideo 3.0
 @item RV40 @tab RealVideo 4.0
 @item SNOW @tab FFmpeg Snow
 @item SVQ1 @tab Sorenson Video 1
 @item SVQ3 @tab Sorenson Video 3
 @item theo @tab Xiph Theora
 @item TM20 @tab Truemotion 2.0
 @item UMP4 @tab non-compliant MPEG-4 generated by UB Video MPEG-4
 @item VCR1 @tab ATI VCR1
 @item VP30 @tab VP 3.0
 @item VP31 @tab VP 3.1
 @item VP50 @tab VP 5.0
 @item VP60 @tab VP 6.0
 @item VP61 @tab VP 6.1
 @item VP62 @tab VP 6.2
 @item VP70 @tab VP 7.0
 @item WMV1 @tab MS WMV7
 @item WMV2 @tab MS WMV8
 @item WMV3 @tab MS WMV9
 @item WV1F @tab non-compliant MPEG-4 generated by ?
 @item WVC1 @tab VC-1
 @item XVID @tab non-compliant MPEG-4 generated by old Xvid
 @item XVIX @tab non-compliant MPEG-4 generated by old Xvid with interlacing bug
 @end multitable