Gknot+hyperthreading

[Fabrian]

Is there any way to make Gordian Knot use 100% cpu on a hyperthreading system?? using only 50% takes waaaaaayy too long..

[manono]

Hello and welcome to the forums-

GKnot is just a front end for the programs it uses. It's those programs that have to be optimized for hyperthreading, so there's not anything GKnot can do about that. You might try turning off hyperthreading while encoding to see if the encoding is faster. I think it will be.

But I'm just talking off the top of my head. Maybe someone that really knows about these things can comment.

[Fabrian]

Thanks for the reply. I thought about just turning hyperthreading off once before, but never did. I'll give it a try; I have a movie encoding now for like 10 hrs already.... there's no reason for that! :eek:

**Edit---

Actually, I used to use DVDx and that worked just fine for me (3-4 hrs encode single pass) until I started getting audio/video desync and couldn't correct it with newer movies. Using gnot, each pass is taking about 4-5 hrs and I have my machine running at 3.0gig!

[manono]

Hi-

So, what codec and at what settings? If, for example, you're using XviD with VHQ4, that could account for the difference all by itself.

[Fabrian]

I'm using divx5 with the exception of two pass w/gknot instead of single pass with dvdx. Settings are usually set to 2 cd in gknot usually leading to about 1400megs. Maybe I'm doing something wrong, but when I used to use dvdx at a file size of roughly 700-800 megs, the image looked as good if not better. The other thing is when ripping with gknot, I always get a low volume rip, how do I fix that?

Thanks

[manono]

Hi-

GKnot uses VDubMod as the encoder. So I would say that any differences in encoding time or quality of the result would have to do with the settings.

but when I used to use dvdx at a file size of roughly 700-800 megs, the image looked as good if not better.

Unless you're talking about the same movie done at the same settings with both programs, what you said is meaningless. Do you run a compression test in GKnot before running the 2 passes?

I always get a low volume rip, how do I fix that?

You said that you make 2 CD rips, so I'll assume this is the AC3 audio you're talking about? If so, then GKnot has nothing to do with the audio volume. Check your Filter settings. If not, then let me know what audio you make, and exactly how.

[Fabrian]

To keep my response short and sweet, I followed the doom9 gknot guide to a tee HERE (http://www.doom9.org/index.html?/gknot-main2.htm)

**Edit - maybe there's a better guide to follow? I have some other strange things that I'm not sure of either, like in the working folder for the rip, I always wind up with two movies, one with sound and one without. I know I could give you much more info here, but maybe there's a more simple way to get a rip accomplished? Sorry for the vague reply...thanks for you help.

[manono]

Hi-

The guide to which you pointed is for DivX 3.11 SBC, and you said you're using DivX 5. But that's OK, they're similar.

I always wind up with two movies, one with sound and one without.

That's normal. GKnot first encodes the video, and afterwards muxes in the audio and splits.

but maybe there's a more simple way to get a rip accomplished?

You might try AutoGK (http://forum.doom9.org/showthread.php?s=&threadid=64266).

As for your soft audio problem; you still didn't say if it was the AC3 that's too quiet. But if so, and you have the AC3 Filter installed, then go Start->Programs->AC3 Filter->AC3 Filter Config. Then in the lower left corner, where you see Preset, change it to Loud.

And you said that you're following closely the guide, but again, you didn't answer my question. Are you running a Compression Test (Doom9 calls it a compressibility check) before doing the encoding. Following what the results tell you will help insure top quality results.

[Fabrian]

Originally posted by manono
And you said that you're following closely the guide, but again, you didn't answer my question. Are you running a Compression Test (Doom9 calls it a compressibility check) before doing the encoding. Following what the results tell you will help insure top quality results. [/B]

Yes, I'm running a compressability test. I guess I just never understood why some movies can be ripped with really good quality at 700 megs and I'm getting rips that appear equivalent with double the file size.

I used autogk once and it didn't work well at all, but it was still in beta at the time..

I did look at the ac3 settings, which I am using (sorry for not answering that before) and I did see the volume setting you were talking about, that is infact my audio problem..thanks!

[jggimi]

If you're using .ac3 sound in your 2-CD rips, but were using .mp3 in your 1-CD rips, the capacity requirements difference is certainly one reason why you may not see significantly improved video.

A 5.1ch DD soundtrack typically has a bitrate of 448kbps, whereas a typical MP3 soundtrack has a bitrate of 128kbps. For two hours of content, that DD soundtrack is 385MB, while the MP3 soundtrack is 110MB. Using the MP3 soundtrack rather than DD would free up 275MB that could be used for video bitrate improvements. (There are 3 extra MB in overhead for .mp3 compared with .ac3, accounting for the extra overhead would mean 272MB is available for video.)

I understand that your 1-CD rips prior to using Gknot were acceptable to you, and that your 2-CD rips with Gknot are not. But, since you haven't shared any specifics about your encodings, we can only conjecture as to possible reasons. If you have logs (or even samples of .avi files you could share) we might be able to point to specific reasons for the trouble. In the mean time, be sure you're not trying to compare apples and ... diving boards.