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Old 13th November 2008, 00:45   #6961  |  Link
nautilus7
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I was playing around with the new floating point output and i wonder which offers better quality: AC3 decoded with nero (24 bit output) or AC3 decoded with libav to floating point?
What do you think? Is floating point output preferable over nero decoder? For sure the difference will be very small, but i don't have that much expensive equipment to test my self. Can anyone tell?

Last edited by nautilus7; 13th November 2008 at 01:13.
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Old 13th November 2008, 01:08   #6962  |  Link
Snowknight26
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What is the difference between 2 channel AC3 Surround, 2 channel AC3 Headphone and just normal 2 channel AC3?
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Old 13th November 2008, 01:16   #6963  |  Link
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I guess dolby surround is the old "analog" dolby surround pro logic (center and surround channels matrixed into left and right), while dolby headphne is something similar (equivalent), but specially developed for headphones.
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Old 13th November 2008, 02:02   #6964  |  Link
Jeff Flowerday
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Quote:
Originally Posted by Jeff Flowerday View Post
Evan Almighty HD-DVD rip:

When I run eac3to on the rip it doesn't list the feature movie for some reason. All I get is the following:

C:\Users\FlowerdayJ\Videos\EVANALMIGHTY>eac3to .
1) WATERRISING_1.EVO+WATERRISING_2.EVO+RU_GIRAFFE.EVO+RU_ELEPHANT.EVO+RU_LION.EV
O+RU_GORILLA.EVO+RU_WOLVES.EVO+RU_EAGLE.EVO+RU_KOALA.EVO+RU_OTTER.EVO+RU_CHEETAH
.EVO+RU_SURFEIT.EVO+RU_AUSTRALIA.EVO+RU_CHIMP.EVO+RU_GRIZZLY.EVO+RU_LLAMA.EVO+RU
_PEACOCK.EVO+RU_CAMEL.EVO+RU_ORANGUTAN.EVO+RU_ARMADILLO.EVO+RU_GOAT.EVO+RU_ANACO
NDA.EVO+RU_EXITBEFORE.EVO+RU_OUTRO.EVO+RU_EXITAFTER.EVO+RU_END.EVO, 0:04:50
"Animal Round Up"
- VC-1, 1080p (16:9)
- E-AC3, 2.0, 48khz
When I go straight at the drive I get the same result.

Not sure what you use to find the information but I assume the xpl files so I've zipped them up.

http://www.flowerdayconsulting.com/Misc/vpl.zip
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Old 13th November 2008, 04:32   #6965  |  Link
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Quote:
Originally Posted by htpc@rischer.at View Post
Problem 1 (bruce-lee 1.0 ac3)
Sorry, obviously something went wrong. Here the 10mb-file:
http://rapidshare.com/files/161846249/bruce10MB.eac3
This now decodes properly with libavcodec from FFmpeg's current SVN.

Thanks madshi for contacting me directly about this file. It does use spectral extension. I had implemented the feature in the "sandbox" repository from the original Google Summer of Code project, but had not merged to FFmpeg SVN because I only had 1 sample file to test... until now!! With this sample and another (also provided by madshi) working properly, I decided to merge the changes to FFmpeg SVN.
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Old 13th November 2008, 05:02   #6966  |  Link
jruggle
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Quote:
Originally Posted by nautilus7 View Post
I was playing around with the new floating point output and i wonder which offers better quality: AC3 decoded with nero (24 bit output) or AC3 decoded with libav to floating point?
What do you think? Is floating point output preferable over nero decoder? For sure the difference will be very small, but i don't have that much expensive equipment to test my self. Can anyone tell?
Listening tests aside, I doubt the quality is noticeably different. The internal dynamic range for AC3 is 24-bit.

First of all, we don't know what the Nero decoder does internally. It might be completely fixed point, or maybe it uses floating point everywhere and just converts to 24-bit at the end. The lavc decoder uses 24-bit fixed point for everything up to the IMDCT and downmixing in each block. If I had a 24-bit fixed-point IMDCT implementation it would not use floating point at all. The only reason the downmixing is floating point is because it's sometimes done after the IMDCT.
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Old 13th November 2008, 08:31   #6967  |  Link
sehgal.v7
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@Madshi
Do you want sample of Iron Man Audio in TrueHD & DTS HD-MA?
I saw sometime back you needed sample of Same track in two Lossless Formats..
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Old 13th November 2008, 08:50   #6968  |  Link
madshi
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Quote:
Originally Posted by Snowknight26 View Post
What is the difference between 2 channel AC3 Surround, 2 channel AC3 Headphone and just normal 2 channel AC3?
Quote:
Originally Posted by nautilus7 View Post
I guess dolby surround is the old "analog" dolby surround pro logic (center and surround channels matrixed into left and right), while dolby headphne is something similar (equivalent), but specially developed for headphones.
Yep, that's correct. Dolby Headphone I believe is 5.1 downconverted to 2.0 in such a way that it is supposed to still sound like surround when played back by a headphone...

Quote:
Originally Posted by Jeff Flowerday View Post
When I go straight at the drive I get the same result.

Not sure what you use to find the information but I assume the xpl files so I've zipped them up.

http://www.flowerdayconsulting.com/Misc/vpl.zip
For whatever strange reason the "VPLST000.XPL" file only contains some extra stuff. The movie is in the "VPLST001.XPL" file. Never seen that before yet! You can "fix" the problem by deleting "VPLST000.XPL" and renaming "VPLST001.XPL" to "VPLST000.XPL", because eac3to always only checks "VPLST000.XPL".

Quote:
Originally Posted by jruggle View Post
This now decodes properly with libavcodec from FFmpeg's current SVN.
Great - thanks!

Quote:
Originally Posted by jruggle View Post
Listening tests aside, I doubt the quality is noticeably different. The internal dynamic range for AC3 is 24-bit.

First of all, we don't know what the Nero decoder does internally. It might be completely fixed point, or maybe it uses floating point everywhere and just converts to 24-bit at the end. The lavc decoder uses 24-bit fixed point for everything up to the IMDCT and downmixing in each block. If I had a 24-bit fixed-point IMDCT implementation it would not use floating point at all. The only reason the downmixing is floating point is because it's sometimes done after the IMDCT.
Ah, that's interesting...

Quote:
Originally Posted by sehgal.v7 View Post
@Madshi
Do you want sample of Iron Man Audio in TrueHD & DTS HD-MA?
I saw sometime back you needed sample of Same track in two Lossless Formats..
Yes, why not! Such samples never hurt...
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Old 13th November 2008, 12:55   #6969  |  Link
deathlord
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Quote:
Originally Posted by deathlord View Post
madshi

I have a question on the new ac3 ex feature. Dolby digital ex has a 6th channel built in for use in 6.1 or 7.1 setups. Can eac3to decode those tracks to 7.1?


Quote:
Originally Posted by madshi View Post
No.
Any plans on implementing it, or do you intentionally keep these tracks at 5.1 only?
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Old 13th November 2008, 15:34   #6970  |  Link
Jeff Flowerday
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Quote:
Originally Posted by madshi View Post
For whatever strange reason the "VPLST000.XPL" file only contains some extra stuff. The movie is in the "VPLST001.XPL" file. Never seen that before yet! You can "fix" the problem by deleting "VPLST000.XPL" and renaming "VPLST001.XPL" to "VPLST000.XPL", because eac3to always only checks "VPLST000.XPL".

Thank you! Will do.
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Old 13th November 2008, 16:01   #6971  |  Link
htpc@rischer.at
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Quote:
Originally Posted by jruggle View Post
This now decodes properly with libavcodec from FFmpeg's current SVN.

Thanks madshi for contacting me directly about this file. It does use spectral extension. I had implemented the feature in the "sandbox" repository from the original Google Summer of Code project, but had not merged to FFmpeg SVN because I only had 1 sample file to test... until now!! With this sample and another (also provided by madshi) working properly, I decided to merge the changes to FFmpeg SVN.
Great work. bruce10.eac3 was my example-track.
So, when and how can I get this changes in order to convert my track?
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Old 13th November 2008, 19:35   #6972  |  Link
Jeff Flowerday
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Quote:
Originally Posted by madshi View Post
For whatever strange reason the "VPLST000.XPL" file only contains some extra stuff. The movie is in the "VPLST001.XPL" file. Never seen that before yet! You can "fix" the problem by deleting "VPLST000.XPL" and renaming "VPLST001.XPL" to "VPLST000.XPL", because eac3to always only checks "VPLST000.XPL".

Just an FYI, the VPLST001.XPL is formatted weird as well, eac3to wasn't showing any chapters, so I went and deleted the <ScheduledControlList> sections in both Main Movie titles and copied the <ChapterList> section from Title 1 down into Title 27 where it was missing. After doing that eac3to showed me only one Main Movie and it had chapters.

I googled the movie and some people were having trouble with the HD-DVD player freezing on chapter operations with the particular movie. This may very well explain the problems they were having.


Last edited by Jeff Flowerday; 13th November 2008 at 19:43.
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Old 13th November 2008, 19:42   #6973  |  Link
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What about volume normalization, is there a chance we might see that in eac3to? Sometimes tracks that are downmixed from multichannel to stereo are rather low on volume.
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Old 13th November 2008, 21:33   #6974  |  Link
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@Madshi

Quote:
Originally Posted by madshi View Post
First of all it depends on the decoder. I patched libav so that it gives me the full floating point decode. But Nero and Sonic decoders internally downconvert to 24bit PCM. Now with libav eac3to by default downconverts to 24bit PCM if you ask it to create a WAV file. The reason for that is that 24bit PCM is usually plenty good enough. The main purpose of keeping things in floating point is if you want to do further processing on the data or if you want to feed the data to an encoder which wants floating point data. If that is the case, simply use the "-full" switch. Then eac3to will create floating point WAV files (if floating point data is available).
In the educational purposes could you tell please how do you perform (for example) 24 bit to 16 bit downconverting? Just throw out 8 lower bits or doing some sort of companding (applying dynamic compression to dynamic range) similar to mu-law etc?
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Old 13th November 2008, 22:30   #6975  |  Link
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before few month i reported that:

http://forum.doom9.org/showthread.ph...14#post1158014

Sonic Audio Decoder version 5.0.0.203 (from Sonic CineVision 2.5.0) doesn't decode DTS-HD extension and decodes the DTS core only and that version 4.3.0.169 (from Sonic CineVision 2.0.2) is the last one that decodes the DTS-HD extension.

now, Sonic CineVision 2.6.1 is out, it includes version 4.3.0.230 of the decoder.

Sonic has strange version numbering:

Sonic CineVision 2.0.2: Sonic Audio Decoder version 4.3.0.169
Sonic CineVision 2.5.0: Sonic Audio Decoder version 5.0.0.203
Sonic CineVision 2.6.1: Sonic Audio Decoder version 4.3.0.230

maybe, only the last 3 digits are important and they are the build number. anyway, the new version 4.3.0.230 doesn't work with the DTS-HD extension too.

btw, while testing the new version 4.3.0.230 of Sonic i found out something that looks like a bug in eac3to: the same DTS core decoded with Sonic in eac3to and GraphEdit produce different output (not byte by byte indentical), which doesn't seem right.
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Old 13th November 2008, 23:59   #6976  |  Link
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I have a DTS hi-res 7.1 track @ 2084 kb/s I am about to remux for BD playback, however my HT setup is only 5.1. Is the extra kb/s only assigned to the rear surround channels or would there be "hi res" data on the other 6 channels as well?

Basically will I be getting just the core because I have a 5.1 setup? I have an HD audio amp and it is hooked up via HDMI.

Also, when demuxing a DTS HD or DTS HR track should the output be ".dtshd/hr" and would setting it as .dts write a new dts track and leave out the HD data?

Thanks.
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Old 14th November 2008, 00:07   #6977  |  Link
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HD data are used for all channels.

To demux a DTS-HD track you need .dtshd or .dts or even .dtsma/.dtshr (i have never used the last though). To get the core you need the -core switch.
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Old 14th November 2008, 00:20   #6978  |  Link
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Quote:
Originally Posted by nautilus7 View Post
HD data are used for all channels.

To demux a DTS-HD track you need .dtshd or .dts or even .dtsma/.dtshr (i have never used the last though). To get the core you need the -core switch.
So using .dts on a DTS HD/HR would in fact demux all HD data rather than just writing a new DTS track, goo to know.

I was only concerned with the fact that my setup is 5.1, and the DTS HR track I have is 7.1... and was I going to get the extra HD data.

Thanks.
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Old 14th November 2008, 02:09   #6979  |  Link
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Madshi, this may have been asked before so please excuse me if that is the case...

Since Nero 9's filters are once again accessible (as opposed to Nero 8's being locked) through direct show, do you have any plans to incorporate usage of these filters into EAC3to?

I would love to be able to upgrade my version of Nero. I am still using Nero 7, simply because I want to retain full use of your fantastic application. It just seems a shame to not be able to replace an entire multimedia suite due to this.
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Old 14th November 2008, 06:24   #6980  |  Link
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Hey Madshi,

I was wondering if you could add an option to downsize from 8 channels to 7 channels in addition to downsizing from 8 to 6 by combining the Lsr(BL) and Rsr(BR) into Cs(BC?).

When combining this option with extracting to "wavs" would take an 8 channel 7.1 stream and downsize it to 6.1 and output 7 separate wav files which you can then manually feed into a DTS-ES encoder to create a 6.1 DTS-ES track.

What do you think?

Last edited by lithiumus; 14th November 2008 at 06:35.
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