Joining divx files with different bitrates

[headless chicken]

I have two avi files I would like to join together, and then resplit (into 3 files of equal length). However, I believe these files may have different bitrates.

1. How do I check if these files do in fact have different bitrates?
2. If they do, is there anyway to join them?

I eventually plan on converting them to SVCD and then placing the trick VCD header on them. Would it be better to first convert the files to MPEG and then join them?

Here is the file info from VirtualDub. As you can see, the video data rate for the two files are different.

file 1
http://www.dvdrhelp.com/forum/images/guides/p770072/mists1.gif

file 2
http://www.dvdrhelp.com/forum/images/guides/p770072/mists2.gif

[hakko504]

The easiest way to handle this is to NOT join the files, but create an AviSynth script that joins them and feed that script to the MPEG-2 encoder.

Like this:clip1=AviSource(file1.avi)
clip2=AviSource(file2.avi)
total=clip1++clip2
return total.trim(start_of_clip,end_of_clip)By selecting start_of_clip and end_of_clip carefully you can find perfect points for splitting the movie into as many SVCDs as you like.

[Wolfman]

If you use 2 pass VBR encoding and you split an avi into any number of parts, anywhere in its length, the parts will always have different bitrates. The thing that would cause problems is if the avis were different codecs and widely different bitrates (double or half). Your two clips are probably one avi that was split in two anyway! (same codec, resolution and audio)

[esby]

Technically to merge two videos:

Of course, vdub will tell you directly if you can mix a clip
to another one,
but what i'm going to write is more to give you an explanation
of the possible error message vdub will gives to you...


They must have : (for two avi files in one avi file)

* Same codec.

* Same global setting mode
(don't ask me why,
but from what i've heard you could not mix
one pass quality based setting with two pass encode
at a time...
maybe it was corrected, i don't know...)

* Same video framerate.
(it can be tricky, video framerate
is the result of two integer,
so a same framerate does not mean possible muxing,
the check on virtual dub is on the two integer.
If there are not, you need to change avi properties
using a framerate changer...)

* Same audio codec used.
* Same audio sampling rate. ( 44100Khz won't mix with 48000Hz)
* same audio bitrate in case of CBR audio.

about the restrictions:

about codec,
you can mix lo & hi motion of a same codec.

by codec, we are talking of something the given codec will decode.
Not necessary something encoded with it.
(in theory mixing div3 from nandub and div3 from ffvfw is not a problem at all)

There might be some restrictions with the use of Bframes too.

esby