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  #381  
12-22-2002, 08:52 PM
kwag kwag is offline
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Quote:
Originally Posted by SansGrip
I've always had a lot of luck with SCMPX -- it seems to produce really good quality even at low bitrates. I've never tried it lower than 128 though.
I think SCMPX is as good as HeadAC3he, but it's a slower encoder. Still it's excelent.

-kwag
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  #382  
12-22-2002, 08:53 PM
kwag kwag is offline
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Quote:
Originally Posted by kwag
Quote:
Originally Posted by SansGrip
I've always had a lot of luck with SCMPX -- it seems to produce really good quality even at low bitrates. I've never tried it lower than 128 though.
I think SCMPX is as good as HeadAC3he, but it's a slower encoder. Still it's excelent.
Only problem is tht if you want to encode "Surround 2" sound, you need to convert AC3 to WAV with Mediator, in order to encode with SCMPX

-kwag
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  #383  
12-22-2002, 08:54 PM
kwag kwag is offline
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Quote:
Originally Posted by SansGrip
I've always had a lot of luck with SCMPX -- it seems to produce really good quality even at low bitrates. I've never tried it lower than 128 though.
I think SCMPX is as good as HeadAC3he, but it's a slower encoder. Still it's excelent.

Edit: Only problem is if you want "Dolby Surround 2" audio, you need to convert the AC3 audio to WAV in order to use SCMPX to encode .

-kwag
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  #384  
12-22-2002, 08:59 PM
SansGrip SansGrip is offline
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Quote:
Originally Posted by kwag
Only problem is if you want "Dolby Surround 2" audio, you need to convert the AC3 audio to WAV in order to use SCMPX to encode[/color] .
I always encode audio through TMPGEnc (external encoders), and it makes a temporary wav anyway.
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  #385  
12-22-2002, 09:02 PM
kwag kwag is offline
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Quote:
Originally Posted by SansGrip
Quote:
Originally Posted by kwag
Only problem is if you want "Dolby Surround 2" audio, you need to convert the AC3 audio to WAV in order to use SCMPX to encode[/color] .
I always encode audio through TMPGEnc (external encoders), and it makes a temporary wav anyway.
But you're not retaining the dolby surround 2 mode, AKA: Dolby Prologic II. That's the beauty of HeadAC3he. It encodes the .mp2 with that feature. SCMPX doesn't do that. The sound is very close to Dolby 5.1 if you encode with this mode turned on.

-kwag
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  #386  
12-22-2002, 09:06 PM
jorel jorel is offline
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about:
"It would be useful, but I'm guessing it would be quite hard to determine borders automatically. It sounds easy but I don't think it would be . "

i post this link before,but don't remember where......
it's about autoboarder.....:
neopholus (in doom9) make a script for me to make vcds.
maybe it could help!

http://forum.doom9.org/showthread.ph...6&pagenumber=2
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  #387  
12-22-2002, 09:16 PM
SansGrip SansGrip is offline
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Quote:
Originally Posted by kwag
But you're not retaining the dolby surround 2 mode, AKA: Dolby Prologic II.
I've never even heard of that . How does it differ from regular ProLogic? Why does resampling as PCM not retain the surround information?
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  #388  
12-22-2002, 09:31 PM
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Quote:
Originally Posted by SansGrip
Quote:
Originally Posted by kwag
But you're not retaining the dolby surround 2 mode, AKA: Dolby Prologic II.
I've never even heard of that . How does it differ from regular ProLogic? Why does resampling as PCM not retain the surround information?
It is retained. The problem is in the encoding. There is a difference between regular "Dolby Surround" and "Dolby Prologic II". I'm not sure what is the algo used, but I tested a regular WAV encoded with TMPEG at 160Kbps, and the same thing encoded with HeadAC3he as "Dolby Surround 2" and I couldn't believe the sound effects. I think it has to do with the actual separation of rear channels, where in regular surround, rear speakers are one channel. Don''t flame me here . I'm no audio expert :P . This is what I've read, but my ears tell me a HUGE difference between the encodes. BTW: If you run DVD2SVCD, you'll notice that on the Audio tab and then click on the down arrow besides the little folder besides BeSweet, you get a popup dialog that let's you select "Stereo downmix type" . It defaults to "Surround." But you'll see that it has a "Surround 2" option

-kwag
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  #389  
12-22-2002, 09:35 PM
SansGrip SansGrip is offline
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Quote:
Originally Posted by kwag
It is retained. The problem is in the encoding. There is a difference between regular "Dolby Surround" and "Dolby Prologic II".
Ok, so assuming I demux the AC3 with DVD2AVI as usual, what do I need to do to encode the audio with ProLogic II? I really want to try this because I have a nice surround setup and regular ProLogic just doesn't really cut it for me after AC3 .
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  #390  
12-22-2002, 09:45 PM
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Quote:
Originally Posted by SansGrip
Quote:
Originally Posted by kwag
It is retained. The problem is in the encoding. There is a difference between regular "Dolby Surround" and "Dolby Prologic II".
Ok, so assuming I demux the AC3 with DVD2AVI as usual, what do I need to do to encode the audio with ProLogic II? I really want to try this because I have a nice surround setup and regular ProLogic just doesn't really cut it for me after AC3 .
Get HeadAC3he, and when you run it, select "Surround 2" on downmix type on the channel configuration screen ( At the bottom ). Also make sure you select "Dual Channel" NOT STEREO. It makes a hell of a difference on the surround signals being carried to your receiver. If you encode as "Stereo", the small adjacent channel interference from one channel to the other can dampen your dolby surround signals, and your receiver may not detect your channel separation signals correctly. When you encode as "Dual Channel" each channel is 100% independent of each other. That is, adjacent channel rejection is i believe >100db, so basically it's like two independent mono channels.

-kwag
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  #391  
12-22-2002, 10:12 PM
SansGrip SansGrip is offline
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Quote:
Originally Posted by kwag
Get HeadAC3he, and when you run it, select "Surround 2" on downmix type on the channel configuration screen ( At the bottom ). Also make sure you select "Dual Channel" NOT STEREO.
And then just encode as mp2?

Does this only work for AC3 sources? Do all AC3 sources contain ProLogic II information, or just some? If just some, how can I tell which do and which don't? Do I need the 5.1 AC3 or can I use the 2-channel AC3, assuming the DVD contains both?
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  #392  
12-22-2002, 10:24 PM
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Quote:
Originally Posted by SansGrip
And then just encode as mp2?
Right!
Quote:

Does this only work for AC3 sources? Do all AC3 sources contain ProLogic II information, or just some? If just some, how can I tell which do and which don't? Do I need the 5.1 AC3 or can I use the 2-channel AC3, assuming the DVD contains both?
What it's doing is down mixing the AC3 ( Digital 5.1 ) channels to Dolby Surround Mode 2. If your DVD has a DD 3/2 channel, use that channel. Just make sure you pick the right channel, as viewed on DVD2AVI preview. That's the channel I always convert to .mp2, usually Channel 1

-kwag
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  #393  
12-22-2002, 10:32 PM
SansGrip SansGrip is offline
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Quote:
Originally Posted by kwag
What it's doing is down mixing the AC3 ( Digital 5.1 ) channels to Dolby Surround Mode 2. If your DVD has a DD 3/2 channel, use that channel.
Ok. I usually pull off just the 2-channel version if there is one, since it's smaller. But if the ProLogic II information is only in the 5.1 version then I'll make sure to get that. Maybe it's time to ask Dr Google about ProLogic II .
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  #394  
12-22-2002, 10:35 PM
muaddib muaddib is offline
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Quote:
Originally Posted by kwag
If your DVD has a DD 3/2 channel, use that channel. Just make sure you pick the right channel, as viewed on DVD2AVI preview. That's the channel I always convert to .mp2, usually Channel 1
Are you saying that a 3/2 channel is better for mp2 than 5.1 channel?
It is something that I always feel… but never knew.
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  #395  
12-22-2002, 10:35 PM
kwag kwag is offline
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Quote:
Originally Posted by SansGrip
Maybe it's time to ask Dr Google about ProLogic II .
Prologic != Prologic II

-kwag
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  #396  
12-22-2002, 10:37 PM
SansGrip SansGrip is offline
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Quote:
Originally Posted by kwag
Prologic != Prologic II
I'll make sure I'm reading about the right version .
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  #397  
12-22-2002, 10:37 PM
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Quote:
Originally Posted by muaddib
Are you saying that a 3/2 channel is better for mp2 than 5.1 channel?
It is something that I always feel… but never knew.
No, it's not better than 5.1. That's impossible
But Dolby Prologic II is way better than regular surround

-kwag
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  #398  
12-22-2002, 10:39 PM
SansGrip SansGrip is offline
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Quote:
Originally Posted by muaddib
Are you saying that a 3/2 channel is better for mp2 than 5.1 channel?
I might be wrong but I assumed they were the same thing. 3 front channels, 2 rear. The only difference is that a 5.1 has a separate sub-woofer channel.
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  #399  
12-22-2002, 10:39 PM
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http://www.kvcd.net/forum/viewtopic....light=prologic
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  #400  
12-22-2002, 10:44 PM
muaddib muaddib is offline
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Quote:
Originally Posted by kwag
No, it's not better than 5.1. That's impossible
But Dolby Prologic II is way better than regular surround
Yes, I know that 5.1 is better, but we can't have 5.1 with .mp2, can we?
So, if my DVD has both 5.1 and 3/2... Which should I choose to convert to mp2 with surround 2 downmix?
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