Unpacking bitstream with MPEG4Modifier

[GangstaRap]

I have few AVI files and i want to unpack their bitstream.
so i been told to use MPEG4Modifier, so i did but i have a little question:

when i'm tickin the box here:


the "user data" is changing to this:


what is that user data?

should i leave it? is it matter?

thanks in advance!

[Soopafresh]

Here's something I never knew before. Spread the word when someone else asks the same question.

http://www.mpcclub.com/modules.php?name=Forums&file=viewtopic&p=79916#79916

[GangstaRap]

Soopafresh, thanks but i dont have any
problems with playing the video...

i just want to know what is this user data?
is it the header?
why is it changin?

[Abond]

Then why you want to unpack the bitstream?

[GangstaRap]

Abond, my PC handle it very well
but my DVD Player (Pioneer DV-383) plays it like it had 10 PFS movie in it.

[Abond]

A-ha, but you said you have no problems playing the file... Anyway.
The link Soopafresh gave you deal exactly with DVD Player playback. Did you try the trick described there?

[celtic_druid]

Problem is with packed bitstream and multiple consecutive bframes combined with bad firmwares on MTK based players. The issue is that when you have multiple bframes, only the first is packed. Unpack and both are unpacked so there is no problem. Also with one packed bframe it isn't an issue.

Interestingly "DivX503b1393" is the newer string. DivX999b000 was the old string which was updated along with some other changes for DivX compatibility. No idea what is up with Kiss' firmware. Guess they hard coded it for old Xvid encodes.

String was changed some time between v1.0.x and 1.1.x. So v1.0.x encodes would work on the Kiss player but v1.1.x and 1.2.x wouldn't despite the better hardware compatibility offered by newer builds.

Also from recollection with auto ticked older MPEG4Modifier builds kept the DivX user data string, but removed the "p" when unpacking.

[GangstaRap]

A-ha, but you said you have no problems playing the file... Anyway.

right, but the mainly reason i'm asking it is curiosity...