XviD compatibility with future versions and future decoders

andy

Hi, my question deals with the concerns I have that some of the videos I have encoded with older versions of XviD may not be compatible with future versions or future decoders such as ffdshow.  I'm asking to see if those concerns are valid, or if I can expect future versions to be backward compatible.  In all of my 2-pass encodes, I use default settings only.  I am hoping to find out what XviD version is safest to use now so that I can be assured that future versions or decoders will be able to play back the video correctly.

I've been using XviD in my video work for the last year or so, and I update the version I'm using every once in a while using Nic's binaries.  I have mostly used XviD--as opposed to ffdshow--to view the videos.  For the last few months, I had been using 10/29/2002 binary.  However, when I installed the 11/25/2002 or 12/23/2002 binaries, I noticed that some of the videos I had encoded using the 10/29 version played back incorrectly.  Additionally, the 10/29 encodes were extremely incompatible with the 6/28/2002 version.  Videos that had been encoded with the 6/28/2002 binary that I had play back fine with all three versions listed here.  The 1/3/2003 ffdshow alpha plays back all of the XviD encodes properly.

An example of what I'm talking about can be found here.  This video was encoded with the 10/29 binary.

I'm worried about future incompatibilies with my encodes, and I'm wondering what version I should use.  Newer versions might have higher quality features, but they may have experimental methods that will not be supported in future versions.  I'm confused about why newer versions would not decode the older encodes properly, and I'd like to hear any theories about that.  Will ffdshow continue to be able to decode all current and future XviD encodes?  The keyframes are fine; the incompatibilities occur in the delta frames.

So, what's responsible for these incompatibilities?  Is there something quot;wrongquot; with the 10/29, 11/25, or 12/23 versions?  Should I stick to the 6/28/2002 version or another version to be safe?

If you use anything besides the stable build, the video you're creating may not be MPEG-4 spec-compatible.  This has happened a few times in the development builds with regards to B-frames and QPel.

You can use the unstable development builds if you like, but all video you encode with that build may end up an incompatible waste of time.

-h

I think I speak for the developers when I say that an effort will be made to keep compatibility between different XviD builds.

However, sometimes it can't be helped.  Incompatibilities have to occur now and then.

For example, at one point XviD produced buggy QPel video streams.  When QPel was corrected, videos encoded with buggy QPel were broken.  Luckily, there is a workaround available in ffdshow that will allow for the playback of these files.  However, I would not depend on the availability of future workarounds to maintain compatibility.

I think a much better solution would be to stick with a stable build.  Stable builds are almost 100% guarenteed to produce Mpeg4 compatible video streams, and thus should be compatible no matter what.

The problem with stable builds is that they do not contain the latest features, and they are not updated often.

The thing about unstable builds is that they are...unstable.  They may not produce reliable video streams, and they may have errors in them from time to time.  Errors that causes compatibility to break.  That's something that we all should keep in mind.

*Edit*
I took WAY too long to type this up.  -h got there before me.

Thank you, -h and gldblade.  I was wondering if you knew of a technical explanation for the behavior exhibited in the examples I posted here.  I've encoded quite a few personal captures using the 06/28/2002 and 10/29/2002 binaries and was wondering where I could find a list of any suspected bugs or incompatibilities.  Also, is there a way to determine what XviD build a video was encoded with?

What is the latest stable build available?  Out of Nic's, Koepi's, and uManiac's site, the only stable build I see listed is XviD.Root.27.11.2002.0020.exe at uManiac's.  I see a reference to Koepi's stable XviD-04102002-1.exe build in About Koepi's latest stable build.  I believe that the 06/28/2002 Nic binary may be a stable build.

Does exist any exact ISO standard for Q-pel and GMC?
Why are XviD's and DivX's implementations incompatible?

From what I've read, the Mpeg4 specs does not describe the exact file structure for certain things.  I'm not sure if this applies to GMC and QPel, but I know B-frames is one such example.

Does exist any exact ISO standard for Q-pel and GMC?
Why are XviD's and DivX's implementations incompatible?

DivX I don't know,
XviD not intentionally, only due to bugs or quot;roundingquot; bugs in dev builds, but from what I see with videos by latest binaries, with Envivio ISO MPEG-4 player they looks like bomb! And mines are all flasked directly in YV12!

From what I've read, the Mpeg4 specs does not describe the exact file structure for certain things. I'm not sure if this applies to GMC and QPel, but I know B-frames is one such example.

great :-|

Is it possible to get a list of those builds that are/where non-compliant and is there a way to use virtualdub to 're-build' non-compliant video streams?

Actually, I might be wrong about the B-frames.  I thought Mpeg4-compatible decoders could decode XviD B-frames...

So what is the latest stable build available?  Is there a place where I can download the binary?

Edit: Is it Koepi's XviD-04102002-1.exe found at ~koepi/xvid.shtml?

Thanks.

I have last questions.

Is actual q-pel implementation in XviD quaranteed for back-compatibility?
May be any big modification in future anymore?
I think, that the last big modification has been in half of october 2002. Next modifications was only 'little' bug corrections.

Originally posted by Y7
So what is the latest stable build available?  Is there a place where I can download the binary?

Edit: Is it Koepi's XviD-04102002-1.exe found at ~koepi/xvid.shtml?

yep

Can anyone confirm that 06/28/2002 is Nic's latest stable build, and does anyone know where it (or the latest one) might be available?

Mr. B