DVD2AVI has problems with 'The Matrix' ?

[krystof]

Hi everyone,

I tried a 2 CD DVD rip of 'The matrix' using DVD2AVI 1.76, VFAPI & NanDub and DivX 3.11. The source is a Reg 2 PAL DVD, 720 x 576 (german version).

Everything seemed to work fine, only the result of NanDub showed serious (Mpeg2-decoding?) errors: bad blocks that appear only in high-motion scenes, e.g. Morpheus fighting Neo. I checked that the error is already there in the VFAPI file, so it's definitely not a DivX codec/NanDub problem. The problem is also there with DVD2AVI 1.74.

Since I already did over a dozen of successful rips using the same combination of programs, I believe that it is a problem with that particular DVD.

I cross-checked with the latest FlaskMpeg version, here everything was fine (except for the somewhat limited quality of FlaskMpeg ...).

Any suggestions about what I could try to get it work with SBC / DivX3 encoding ? (DivX 4 is not an option because to me it looks worse than DivX 3).

I hope you don't tell me to use AviSynth, because I already tried and could not get AviSynth frameserving to work at all.

Regards,

Krystof

[Kedirekin]

Sounds to me like your DVD is dirty or damaged, so that the rip has bit-errors in it.

Can you borrow or rent another copy?

[krystof]

That's what I first thought, too. But then, why is the error gone with FlaskMpeg ? I don't think that Flask could possibly 'smoothen' away the big ugly blocks.

Well, I have another friend who could lend me his copy. In case the problem is still there, I'll submit this as a bug report to the developers of DVD2AVI.

Thanks for answering, bye,

Krystof

[Philippas]

As i posted before in this forum DvD2AVI uses an MMX IDCT which might be the problem in decoding Mpeg-2 streams. If you run a test in Flask the MMX IDCT is the one that produces the most errors.
It would be a good idea to port miha's IDCT to DvD2AVI.
Ogo might be able to do that cause he is working now with DvDAVI.

[krystof]

Aha, interesting! You mean, there are known problems with DVD2AVI's Mpeg2-decoding?

However: Using iDCTAlgorithm -> IEEE 1180 Reference and -> 64bit-floating point in the DVD2AVI options gave me the same bad results.

Krystof

[Philippas]

Sorry Miha's IDCT was already implemented in DvD2AVI.Read the Thread in the forum: To Ogo

[sneeky]

I have noticed the aforementioned decoding bug in DVD2AVI as well. I have seen it on several movie rips. I have also noticed the same decoding error using Mpeg2Avi but Flask has not exhibited the same error. I do have a procedure to avoid this decoding error and will outline it as follows.

When ripping the movie from the DVD, rip to chapter limits rather than VOB limits. This can easily be done using a tool such as SmartRipper. For example, for a 30 chapter movie, rip chapters 1-15 to one VOB, and chapters 16-30 to another VOB.

As to speculation why this works, I suspect that all VOBs don't start on a Keyframe. The transition from a VOB to VOB that doesn't start on a keyframe leads to decoding errors for a few number of frames. When you rip to chapter limits, it is highly likely that a new chapter starts on a keyframe and avoids this decoding issue.

[poopity poop]

can someone give me a link or explain the difference between 32-bit 64-bit and IEEE 1180 things? Which is better, what are the strengths and weaknesses?

[philippas]

Check it here:http://www.doom9.org/idct.htm