DGDemux development

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Sherman
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Re: DGDemux development

Post by Sherman »

I was scared to tell you, Bullwinkle. DG is stuck in the future. We don't know how it happened on a routine Wayback journey, and we don't have any ideas about how to get him back. So sorry.
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Natasha
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Re: DGDemux development

Post by Natasha »

Sherman murdered DG.
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Sherman
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Re: DGDemux development

Post by Sherman »

It was an accident!
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Albert
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Re: DGDemux development

Post by Albert »

Hope I am not out-of-line in saying that what Sherman has done with the DGDemux performance enhancement is really quite remarkable, and he is to be highly commended for it. He and I are working together to modify the Wayback Machine to support trips to the future. One would expect the time symmetry of deterministic reality to allow this. We anticipate bringing DG back very soon.
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dennis
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Re: DGDemux development

Post by dennis »

Is the comment from mlp project still correct regarding truehd frame :
DGDemux deletes a minor frame at every segment boundary, which is better still, but not perfect yet
source : https://github.com/domyd/mlp
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Rocky
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Re: DGDemux development

Post by Rocky »

Correct. Read the thread here if you are interested in the details.
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gonca
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Re: DGDemux development

Post by gonca »

but not perfect yet
The audio and video frames/samples have different duration.
Perfection is an illusion in this case.
You have to consider time usage, coding complexity etc
How sensitive are your ears?
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gonca
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Re: DGDemux development

Post by gonca »

Can anyone detect a 10ms desync with eyes and ears?
And don't forget that the playback chain can also introduce a couple of millisec into it
AVR>Video>TV
AVR>Audio>Amp>Speakers

Then you have the speed of light vs speed of sound :lol:
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Rocky
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Re: DGDemux development

Post by Rocky »

I ran both algorithms on MONSTERS_UNIVERSITY and found a 5ms difference in total duration. DGDemux is deleting more frames because it does not attempt to compare the audio frames to see actual duplicates. However, claiming that MLP is perfect is simply not true. Actually, it uses a statistical test involving covariance to compare the frames, which seems strange to me. There is an arbitrary threshold (95%) for covariance. Also, when there is silence at a gap, frame comparison is abandoned. And how good is the test for silence? So my point is that MLP also cannot be considered perfect or definitive. Is it better? Perhaps, perhaps not. It's not worth worrying about 5ms. And the DGDemux method is way faster.

If you look at the Issues at the MLP github you'll see that it is not all peaches and cream with MLP. And domy appears to have stopped working on it (src last modified 7 months ago).
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gonca
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Re: DGDemux development

Post by gonca »

Yeah, seems to have an issue matching video and audio length
Not perfect
Oh well, the grass is always greener type of thing
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Rocky
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Re: DGDemux development

Post by Rocky »

I am of the KISS school. The more complex things are the more ways to go wrong. Of course, Albert will remind us, sure, keep things simple, but not too simple. As simple as possible.
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dennis
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Re: DGDemux development

Post by dennis »

Rocky wrote:
Mon Dec 14, 2020 6:45 am
I ran both algorithms on MONSTERS_UNIVERSITY and found a 5ms difference in total duration. DGDemux is deleting more frames because it does not attempt to compare the audio frames to see actual duplicates. However, claiming that MLP is perfect is simply not true. Actually, it uses a statistical test involving covariance to compare the frames, which seems strange to me. There is an arbitrary threshold (95%) for covariance. Also, when there is silence at a gap, frame comparison is abandoned. And how good is the test for silence? So my point is that MLP also cannot be considered perfect or definitive. Is it better? Perhaps, perhaps not. It's not worth worrying about 5ms. And the DGDemux method is way faster.

If you look at the Issues at the MLP github you'll see that it is not all peaches and cream with MLP. And domy appears to have stopped working on it (src last modified 7 months ago).
So if i understand correctly the only issue that could happen is if you delete a frame when not needed (but you never saw this case), and the wave doesnt align at all, we could hear a pop ( that nobody could notice anyway :) )
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Rocky
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Re: DGDemux development

Post by Rocky »

Yes, that's right, dennis. Studies of packet-based internet audio show that for 20ms packets of audio, perceptibility problems begin when 15% of the packets are affected. Now think about what we have with MONSTERS. We have 0.8ms drops affecting about 0.002% of the stream. Size of the loss and how often it occurs are the relevant variables, and for this use case both of these are extremely low. You're not going to hear any 'pops'.
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thechaoscoder
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DGDemux chapters problem

Post by thechaoscoder »

My first post (finally) :hat:

I demuxed a japanese BD with the "episodes demuxing" option. Perfect demux of episodes except for the chapters.
Some episodes have multiple 00:00:00 lines. Some look ok. The first episode chapters file contains also the chapters of the last episode. :scratch:

I created a "DiscShare" version https://forum.doom9.org/showthread.php?p=1893719 of the BD.
Can I post a link in Attachments or should I send the download link to Rocky? via PN? What is the preferred way?
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admin
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DGDemux development

Post by admin »

Send PM to Rocky to discuss.

What is going on here? A first poster already Moose Approved. I don't get it.

Welcome to the forum!
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Rocky
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DGDemux development

Post by Rocky »

Sweet. It will be great to get episode demuxing shaken down. Looking forward to more details. Respect.
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thechaoscoder
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DGDemux development

Post by thechaoscoder »

I got promoted by this epic hacker videoh. Soon I will be Site Admin! :belly-laugh:

ChaosKing (doom9) <=> thechaoscoder
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Sherman
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DGDemux development

Post by Sherman »

Winkie is running wild. We need to rein him in.
thechaoscoder wrote:
Sat Jan 16, 2021 5:28 pm
Soon I will be Site Admin!
Don't get your hopes up, pal. I already have dibs on that. And you haven't even earned your spurs yet!

So yeah, Albert brought me back to the present. And guys, I'm so excited. We now have a reliable mechanism for travel into the future and the Wayback Machine has been modified to support it.

All right, let's get busy on thechaoscoder's bug report.
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Bullwinkle
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DGDemux development

Post by Bullwinkle »

Welcome back, kid.

Herewith, according to my inherent powers and benevolent discernment, thechaoscoder is awarded his spurs.

Image
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Rocky
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DGDemux development

Post by Rocky »

I got the chapters fixed for episode demuxing. I'll make a slipstream in a little while.
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Rocky
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DGDemux development

Post by Rocky »

Chapters fix released in slipstream 48.
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thechaoscoder
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DGDemux development

Post by thechaoscoder »

Thank you. The demux is perfect now :mrgreen:
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Rocky
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DGDemux development

Post by Rocky »

Great. Thank you for your testing.

Today I am going to work on CLI automation for DGMPGDec.
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