.TH avisplit 1 "25th June 2003" "avisplit(1)"
.SH NAME
avisplit \- split AVI-files into chunks of a maximum size
.SH SYNOPSIS
.na
.B avisplit
[
.B -i
.I file
.B -o
.I base
[
.B -s
.I size
] [
.B -H
.I num
] [
.B -t
.I s1-s2[,s3-s4,..]
.B -c
.B -m
.B -b
.I num
.B -f
.I commentfile
]
] [
.B -v
]
.SH COPYRIGHT
\fBavisplit\fP is Copyright (C) by Thomas Oestreich.
.SH DESCRIPTION
.B avisplit
splits a single AVI-file into chunks of size \fIsize\fP.
.br
Each of the created chunks will be an independent file, i.e. it can
be played without needing any other of the chunk.
.SH OPTIONS
.TP
\fB-i\fP \fIfile\fP
Specify the filename of the file to split into chunks.
.TP
\fB-o\fP \fIbase\fP
Specify the base of the output filename(s) \fBavisplit\fP will then split to
\fBbase-%04d.avi\fP
.TP
\fB-s\fP \fIsize\fP
Use this option to specify the maximum size (in units of MB) of the
chunks \fBavisplit\fP should create. \fI0\fP means dechunk, create as many
files as possible.
.TP
\fB-H\fP \fInum\fP
Create only the first \fInum\fP chunks then exit.
.TP
\fB-t\fP \fIs1-s2[,s3-s4,..]\fP
Split the input file based on time/framecode (hh:mm:ss.ms)
.TP
.B -c
Together with \fB-t\fP. Merge all segments into one AVI-File again instead
generating seperate files.
.TP
.B -m
Together with \fB-t\fP. Force split at upper bondary instead of lower border.
.TP
\fB-b\fP \fInum\fP
Specify if avisplit should write an VBR mp3 header into the AVI file. Default is
1 because it does not hurt. \fInum\fP is either 1 or 0.
.TP
\fB-f\fP \fIcommentfile\fP
Read AVI tombstone data for header comments from \fIcommentfile\fP. See
/docs/avi_comments.txt for a sample.
.TP
.B -v
Print only version information and exit.
.SH EXAMPLES
The command
.PP
.B avisplit -s 700 -i my_file.avi
.PP
will split the file \fImy_file.avi\fP into chunks which's maximum size
will not exceed 700 MB, i.e. they will fit onto a CD, each.  The
created chunks will be named my_file.avi-0000, my_file.avi-0001, etc.
.PP
.B avisplit -i my_file.avi -c -o out.avi -t 00:10:00-00:11:00,00:13:00-00:14:00
.PP
will grab Minutes 10 to 11 and 13 to 14 from my_file.avi and merge it into out.avi
.SH BAD SYNCH
When you split a file with \fBavisplit\fP and the A/V sync for the first file
is OK but the sync on all successive files is bad then have a look at the
output of tcprobe(1) (shortend).

.br
 | V: 25.000 fps, codec=dvsd, frames=250, width=720, height=576
.br
 | A: 48000 Hz, format=0x01, bits=16, channels=2, bitrate=1536 kbps,
.br
 |    \fI10\fP chunks, 1920000 bytes
.br

You'll see the AVI file has only 10 Audio chunks but 250 video
chunks. That means one audio chunk spans several video frames.
avisplit can not cut a chunk in half, it only handles complete
chunks. If you do, say, avisplit -s 20, it is possible that the first file will
have 6 audio chunks and the second one only 4 meaning there is too much
audio in the first AVI file.

The solution is to remux the AVI file with
.RS
.B transcode -i in.avi -P1 -N 0x1 -y raw -o out.avi
.RE
(of course -N 0x1 is not correct for all AVI files).
Now look at tcprobe again

.br
 | V: 25.000 fps, codec=dvsd, frames=250, width=720, height=576
.br
 | A: 48000 Hz, format=0x01, bits=16, channels=2, bitrate=1536 kbps,
.br
 |   \fI250\fP chunks, 1920000 bytes
.br

The data in this file is \fIexactly\fP the same (its bit-identical)
as it was in in.avi; the AVI file was just written in a
different way, we do now have 250 audio chunks which makes splitting much
easier and more accurate for avisplit.
.SH AUTHORS
.B avisplit
was written by Thomas Oestreich
.br
<ostreich@theorie.physik.uni-goettingen.de> with contributions from
many others.  See AUTHORS for details.
.SH SEE ALSO
.BR aviindex (1),
.BR avifix (1),
.BR avimerge (1),
.BR tccat (1),
.BR tcdecode (1),
.BR tcdemux (1),
.BR tcextract (1),
.BR tcprobe (1),
.BR tcscan (1),
.BR transcode (1)