Joining AVI files... Would this work??

[mh2360]

Assuming that the AVI files are of the same dimensions, frame rates, codecs etc.. I could strip the header from the second file and append the first file with it. Then I would re-write the header of the first file, probably just altering the number of frames, would this work

[borax]

It should work, but I have never tried it (yet). It can depend on the avi file itself, as AVI is just a container for videos with different codecs. Maybe some codecs add something like a timestamp for frames or GOPs, this may cause problems with the mentioned method.

[metropolis2004]

As there are sepearte tools (e.g. VirtualDub) who are capable of joining, somebody must have programmed them. It's obviously not a problem.

[tigerman8u]

if they're the same as you stated join them in vdub with the append avi.

[vhelp]

..but mh2360 wants to do this through code, that he wants to create
as a tool, I think ..that's why he posted here in the
Programmers area

I used to think the same thing.., that it *should* be easy. But, it
turned out to be more dificult than what it seems. But, in time,
and with some studying, one can figure it all out, and cook up a
tool to do it.., provided some rules are followed ...

If you really want to get into AVI meat, look for a file called:

* vfw.h (or vfw.c) --- C/C++
* vfw.pas ------------ Pascal (delphi) code
* vfw.bas ------------ VB (visual basic)

IMO, it would probably be best to first understand how a BITMAP is
put together, because BITMAP's are the basic building blocks for
an image/video. (One day soon, I hope to come up with my own codec,
to add to the many that are already out there, but its just pretty
slow for me, because I have many other things to attend to)

If you study the vfw.pas (and find some good *short* code examples
on putting together AVI's from scratch, you could figure out how to
do it in shorter code, and use a more *direct* approach in your goal
of creating a util to "join" AVI files.

But, for now, here is something to look at, to get an idea of how an
AVI is put together, and also might show you why its not so easy at
first glance.
.
Below, is a snip from a FAQ I found some time ago. Later, you can do
some additional google searching for more info and knowledge. There's
tons of info. But, the problem is in *understanding* all the code snips
that are floating around. C/C++ is the hardest to understand. But,
there are a lot of info for Pascal (delphi) code snip that is a bit
more easy to digest (still tough for me though)

From an AVI.FAQ file I found on the web some time ago.

----- -- ----- -- ---------- -- ----- -- ---------- -- ----- -- ---------- -- ----- --

What is the AVI File Format?

AVI Files are a special case of RIFF files.  RIFF is the
Resource Interchange File Format.

   RIFF files are built from
	(1) RIFF Form Header
            'RIFF' (4 byte file size) 'xxxx'
            where 'xxxx' identifies the specialization 
            (or form) of RIFF.  'AVI ' is an example.

	(2) A Chunk
		(4 byte ident) (4 byte chunk size) (data)

	(3) A List
          'LIST' (4 byte list size) (4 byte list ident)
          (data) where the data is comprised of LISTS or
          CHUNKS.

AVI is a specialization or "form" of RIFF, described below.

'RIFF' (4 byte file length) 'AVI ' // file header
'LIST' (4 byte list length) 'hdrl' // list of hdrs for
        AVI file
'avih' (4 byte chunk size)  (data) // AVI header
'LIST' (4 byte list length) 'strl' // stream list
'strh' (4 byte chunk size)  (data) // video stream header
'strf' (4 byte chunk size)  (data) // video stream format
'LIST' (4 byte list length) 'strl' // stream list
'strh' (4 byte chunk size)  (data) // audio stream header
'strf' (4 byte chunk size)  (data) // audio stream format
       (optional junk chunk to align on 2K byte boundary)
'LIST' (4 byte list length) 'movi' // list of movie data
        one or more ...
 'LIST' (4 byte list length) 'rec '
 '##wb' (4 byte chunk size)  (data)// sound data
 '##dc' (4 byte chunk size)  (data)// video data

 optional index
 'idx1' (4 byte chunk sz) (index data) //index into movie

 Each 'rec ' list contains the sound data and video data
 for a single frame in the sound data chunk and the video
 data chunk.

 The sound data is typically 8 or 16 bit PCM, stereo or
 mono, sampled at 11, 22, or 44.1 KHz.  The sound is
 typically uncompressed.

-vhelp 3351

[hhhhbk]

use one of

virtual dub
nandub
virtual dub mod

file -> append avi segment to keep adding all the parts
video -> direct stream copy
file -> save as

takes approx 1 minute per hour of video