Provided by: transcode_1.1.7-9build4_amd64 bug

NAME

       aviindex - Write and read text files describing the index of an AVI file

SYNOPSIS

       aviindex [ -o ofile -i ifile -f -n -x -v -h ]

COPYRIGHT

       aviindex is Copyright (C) 2003,2004 by Tilmann Bitterberg

DESCRIPTION

       aviindex  writes  a text file describing the index of an AVI file. It analyses the content
       or index if available of the AVI file and prints this  information  in  a  human  readable
       form.

       An  AVI  file  can  have  an optional chunk called "idx1" which contains information about
       keyframes (syncpoints) and locations of video frames resp. audio chunks. Though larger AVI
       files  (>2-4GB),  so-called  OpenDML  AVI  or  also  AVI  2 files, have a more complicated
       indexing system, which consists of a superindex referring to (possibly) several "standard"
       indexes,  the "indexing principle" is the same.  Movie players use such indexes to seek in
       files.

       aviindex reads the AVI file ifile and writes the index into ofile. This can either  happen
       in "dumb" mode where aviindex looks for an existing index (and trusts this index!)  in the
       file and dumps this index into a human readable form. The "dumb" mode is used, when -n  is
       NOT specified or when the filesize of the input file is smaller than 2 GB.

       In "smart" mode, aviindex scans through the complete AVI file and searches for chunks (may
       that video or audio) and reconstructs the index based on  the  information  found.  If  an
       index  chunk  is  found  accidently,  aviindex  will  use the information in this index to
       recover the keyframe information, which is important. aviindex will  use  smart  mode,  if
       given  the  -n  option  OR  if the AVI file is larger than 2 GB. If the file is large, the
       index chunk cannot be found the usual way so one must use -n but it is possible that there
       is an index chunk in this file. Cross fingers.

       Also  in  smart mode, aviindex analyzes the content of the video frame and tries to detect
       keyframes by looking at the data depending on the video codec.

       The generated index file serves different purposes.

              *      The library which handles AVI files in  transcode(1)  can  read  such  index
                     files and use this file to rebuild the index instead of scanning through the
                     whole AVI file over and over again. Reading the index from the index file is
                     much faster than scanning through the AVI.

              *      It can be used as a seeking file. When given to transcode via the --nav_seek
                     switch, transcode will use the file to seek directly  to  the  position  you
                     specified via -c. This also works for multiple -c ranges.

              *      Its nice to have for debugging.

OPTIONS

       -o ofile
              Specify the name of the output file.

       -i ifile
              Specify the name of the input file.

       -f     force the use of the existing index.

       -n     force generating the index by scanning the file.

       -x     (implies -n) don't use any existing index to generate keyframes.

       -v     show version.

       -h     show help text.

MPLAYER

       aviindex  can  convert  from  and  to mplayer-generated index files. Since mplayer-1.0pre3
       mplayer has the ability to save the index via -saveidx FILE  and  load  it  again  through
       -loadidx  FILE.   aviindex  is  able to convert an mplayer index file to a transcode index
       file and vice visa. It is not able to directly write an mplayer file, though. Example of a
       toolchain
         mplayer -frames 0 -saveidx mpidx broken.avi
         aviindex -i mpidx -o tcindex
         avimerge -x tcindex -i broken.avi -o fixed.avi
       Or the other way round
         aviindex -i broken.avi -n -o broken.idx
         aviindex -i broken.idx -o mpidx
         mplayer -loadidx mpidx broken.avi
       The  major  differences  between  the  two index file formats is that the mplayer one is a
       binary format which is an exact copy of an index in the AVI file.  aviindex ´s  format  is
       text based. See FORMAT for details.

EXAMPLES

       The command

         aviindex -i 3GBfile.avi -o 3GB.index

       generates  and index of the large file 3GBfile.avi. You can use the file 3GB.index to tell
       transcode to read the index from this file and not from the avi. This leads to much faster
       startup time.

       Suppose 3GBfile.avi has DivX video and PCM sound and you want to encode several ranges.

       transcode -V -i 3GBfile.avi --nav_seek 3GB.index \
            -x xvid,avi \
            -c 5000-6000,0:20:00-0:21:00,100000-100001 \
            -y xvid --lame_preset standard -o out.avi

FORMAT

       The  format  of  the  index  file.  The  first 7 bytes in this file are "AVIIDX1" for easy
       detection and a comment of who created the  file.   The  second  line  is  a  comment  and
       describes the fields. Do not delete it. Each line (except the first 2) consists of exactly
       8 fields all seperated by one space and describing one particular chunk of the AVI file.
       Here is an example of an AVI file with two audio tracks.

              AVIIDX1 # Generated by aviindex (transcode-0.6.8)
              TAG TYPE CHUNK CHUNK/TYPE POS LEN KEY MS
              00db 1 0 0 2048 8335 1 0.00
              01wb 2 1 0 10392 847 1 0.00
              01wb 2 2 1 11248 847 1 0.00
              02wb 3 3 0 12104 847 1 0.00
              02wb 3 4 1 12960 847 1 0.00
              00db 1 5 1 13816 5263 0 0.00
              00db 1 6 2 19088 3435 0 0.00
              01wb 2 7 2 22532 834 1 0.00

       The field TAG is the chunk descriptor. Its "00d*" for the  video,  "01wb"  for  the  first
       audio track, "02wb" for the second audio track and so on.

       The  field  TYPE  is  the  type  of  the chunk. This is redundant because the type is also
       embedded into the TAG field but its a convenient thing to have. Its 1  for  video,  2  for
       first audio track and 3 for second audio track.

       The  field CHUNK is the absolute chunk number in the AVI file. If you read the CHUNK field
       in the last line of the index file, you know how many chunks this AVI file has.

       The field CHUNK/TYPE holds information about how many chunks of this type were  previously
       found in the AVI file.

       The field POS is the absolute byte position in the AVI file where this chunk can be found.
       Note this field can hold really large numbers if you are dealing with large AVIs.

       The field LEN is the length of this chunk.

       The field KEY holds information if this chunk is a keyframe.  In the  example  above,  all
       audio  chunks are key-chunks, but only the first video frame is a key frame. This field is
       either 0 or 1.

       The field MS holds information about how many milliseconds have passed. This field may  be
       0.00 if unknown.

AUTHORS

       aviindex was written by Tilmann Bitterberg <transcode at tibit.org>
       and is part of transcode.

SEE ALSO

       avifix(1),   avisync(1),  avimerge(1),  avisplit(1),  tccat(1),  tcdecode(1),  tcdemux(1),
       tcextract(1), tcprobe(1), tcscan(1), transcode(1), mplayer(1)