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Old 7th July 2005, 17:46   #41  |  Link
plonk420
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Quote:
Originally Posted by SeeMoreDigital
To be honest I would not know about this, as I have not studied the intricacies of the DolbyDigital codec.

Okay, AC3 audio is not in the same league as the audio stream on an DTS CD or even an DTS DVD but as long as the frequency range is something like 20Hz to 18-20kHz and the dynamic range extends to a min of 90db, I reckon given the bitrate, AC3 should work perfectly well.

Can anybody else confirm though?
not entirely sure about the dynamic range, but the "stereo coupling" frequency varies by bitrate (Joint Stereo-like feature, i'm guessing?)
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Old 7th July 2005, 18:45   #42  |  Link
Andrey
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Quote:
not entirely sure about the dynamic range, but the "stereo coupling" frequency varies by bitrate (Joint Stereo-like feature, i'm guessing?)
Dolby is rather secretive on the ac3 specs.
Something with dynamic compression is used by encoder to make movie sound more "natural", something related to "holman expiriment", I think.
But this operation may be(?) optional...
Stereo couling, As far as I know, works different from joint stereo. While js uses only another representation of stereo signal (converting from L/R to M/S) stereo coupling means that above some frequensy (10Khz usually) only one channel (as sum) is encoded.
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Old 7th July 2005, 19:35   #43  |  Link
rubycon
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Those guys at H.F. are rather hypocrite, don't you think?

"as High Fidelity Review does not condone the theft of intellectual property or music piracy, we will not be posting a link to the Rarewares download site at this time. Readers who are looking for further information are advised to check one of the popular search engines or a high-resolution discussion forum for applicable URLs."

Piracy is an issue, but what happens with ligitimate uses?

What happens when the industry rip off our right to make copies? What happens with our right to make a copy to a friend, including your girl-( or boy-) friend ?( maybe not in the US, but in some countries this is a legal use according to the local copyright law)

what will happen when the copyright time has ended ? will verance and other cppm measures stop acting? ( they, for sure, will try to get a forever copyright time, such as the 100 year that is currently lobbying to get legislated in Eurpe)

This world is too weighted toward the rights of content publishers and now this ideology is so deep inside people that everything that defends peoples rights is consider piracy tools. But wait!, we, at H.Fidelity, are not condining it!. Just look yourelf for "Rarewares" in your favourite seach engine!!!.

meanwhile I've moved back to the exciting rediscovery of vinyl. But that's another story.


Rub
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Old 7th July 2005, 19:48   #44  |  Link
mpucoder
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Quote:
Originally Posted by Andrey
Dolby is rather secretive on the ac3 specs.
Not at all, the specs have been available for a long time as part of the ATSC suite of specs. You can download it here Look for A/52A "Digital Audio Compression (AC-3) Standard, Rev. A"
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Old 7th July 2005, 20:12   #45  |  Link
SeeMoreDigital
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Quote:
Originally Posted by rjamorim
...and it's gone
And just when it was starting to get interesting

The idea of converting multi-channel DVD-A to a multi-channel lossless format, such as FLAC, was definitely flagging my attention!


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Old 7th July 2005, 20:40   #46  |  Link
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mpucoder
Big thanks for the link !
Some times ago I searched for such a specs on dolby site and failed...
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Old 7th July 2005, 21:13   #47  |  Link
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Interesting article on DMCA

http://www.wise-intern.org/journal02/maxvilimpoc.pdf

Rub
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Old 7th July 2005, 21:56   #48  |  Link
rubycon
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Analysis on the constitutionality of the DMCA

http://serg.us/paper/dmca_thesis.htm

Interesting how the DMCA is intruding into free speech rights, and how it is actually used to cesor thought and stop free publishing in the internet.



Rub

PD: This thesis states that DMCA complies with US constitution, as oposed to the view of my previous post, that is the document in wich it's author states his doubts regarding its use against free speech and, also, in an international context.

Last edited by rubycon; 7th July 2005 at 22:13.
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Old 8th July 2005, 03:11   #49  |  Link
Nedfu
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I tried burning with Gear Pro but it still hangs when selecting the dvd-a 5.1 or 2 channel mixes. I have to press stop and then restart the disc to access the menu again. The only thing that works is the menu and the dolby digital/video rubbish on the disc.
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Old 8th July 2005, 19:00   #50  |  Link
rubycon
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Flac

Although I'm happy about that FLAC initiative, I think DVD forum is weighted toward MLP lossless.

It would be fantastic to have some free tools to do MLP compliant wave files to be used in DVD-A, but I think MLP doesn't allow free tools. I don't know if the DMCA allows reverse engineering on MLP to allow program interoperability. At least in practice this is being heavyly prosecuted by the lawyers of the media companies, so that DMCA provision is practically useless.

It really socks that the DVD-A standard is not 100% open.

Rub
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Old 8th July 2005, 23:35   #51  |  Link
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Quote:
Originally Posted by rubycon

Piracy is an issue, but what happens with ligitimate uses?

What happens when the industry rip off our right to make copies?

Rub
What happens to me is I stop buying!!! (I hope the pilgolopolists are monitoring this forum!) I bought a couple of DVD-As once, but stopped as soon as I realized the fomat was completely unfair. Ditto for iTunes! If the pigos won't play fair and if the pigos, with their big legal budgets, can shut down the 3rd party tools that enable fair options for the consumer, I won't open my wallet. (Thanks for hosting, however briefly, rjamorim! )

Okay, I know a rant is getting a bit off thread, but this is the thread the pigos will be monitoring and they need to hear how they are killing a major consumer base. Face it, mp3 file sharers don't care about audio quality! Who is buying your DVD-As, you stupid pigos! (DVD-As are not exactly flying off the shelves!) It's not the mp3 file sharers. Get a clue!
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Old 9th July 2005, 09:12   #52  |  Link
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I had a play with the tools and found them partially successful, but obviously in need of more development - maybe this will never happen.

Using dvdaripper you can create the file structure again on your HDD, and assuming that the AUDIO_TS and if you want it VIDEO_TS directories are under 4.38 Gb (I'm too mean to waste dual layers on this) you can burn a compliant disc using GEAR Pro Mastering. This disc will play fine on a pc, or if you mount the files as an iso image on your HDD, without burning the disc. However, when played in a standalone dvd-A player, because of the watermarks, all the functionality is there but when you play a track it either 'mutes' or stops as soon as a watermark is reached.

If you look at the programme dvdaexplorer, this looks at the structure of the disc and allows each mlp track to be seperated out - I'm assuming that the watermarks are still in place. There is an option to convert to a wav file, but this is always greyed out - perhaps a future enhancement. Technically there are programmes, such as Sonic DVD-Audio Creator, which will process mlp files. It has a function that takes each track and creates a RAW and xms? file for each mlp track, but I haven't got a clue how to use this and so have stopped there - I don't know if after this processing that the watermarks are cleaned out.

ppcmripper extracts wav files from the original dvd-audio disc. This seems to work okay but only extracts 2 channel wav files. The documentation says that if the disc is first ripped (I'm assuming using dvdaripper) that the multichannels can also be converted to wav. However, the programme does not have the option to select an input directory (it defaults to the disc drive), so you have to either convert the ripped files to an iso, or burn a disc. I tried this but even then the programme still only produced 2 channel waves.

I'd be interested to hear if anyone else has had a play.
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Old 9th July 2005, 11:10   #53  |  Link
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@calinb Yes me too. I stopped buying DVD's from these ripoff merchants a good while ago. I wait for them to come on Skytv, record them complete with AC3 surround and make my own dvd's. As For Audio theres nothing of interest for me on them. The only CD's I buy these days are direct from the Musician ( I am into Irish trad music and I know most of the musicians anyway being one myself). That way the Musician actually gets paid for his work.
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Old 9th July 2005, 14:12   #54  |  Link
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If anyone had yet to download the tools before they and all traces of their info disappeared from Rarewares you can have a second chance at getting them here.

If however this is now illegal and not allowed on here then I do apologise.
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Old 9th July 2005, 16:35   #55  |  Link
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Interesting development.

I've been doing this for a while though, a different way. Now please forgive the following ignorant question:

I work on a laptop with a Creative Audigy 2 PCMICA sound card - what's the difference between the results you get using this method and just recording "What U Hear" using the Audigy soundcard? Or perhaps a similar situation for someone not familiar with the card - using a digital output to a digital input on a separate computer and recording the result on that second computer?

Thanks,
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Old 9th July 2005, 20:02   #56  |  Link
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I'm not sure about computer sound cards but as I understand it the only way to get multi-channel sound from a dvd-audio is via seperate connections for each channel - if you have a dvd-audio or sacd player, then you have to connect them to your amp using 5.1 cables - you can't just use optical or coaxial as they can't carry the channels - with dvd-video you output an encoded signal, such as DD or DTS to the amp via a coaxial and it does the decoding to multi channels - this isn't the case with dvd-audio - I think. Therefore, if you're using a pc, you'd have to be able to output and input 5.1 channels to capture the necessary wav files. With this method, as it's all done 'internally' on disc, this isn't a problem, although watermarking is.
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Old 9th July 2005, 20:04   #57  |  Link
Morbo
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You can't...

First DVD-A software players KILL your digital out(they don;t work on standalones either).

Unless your uber rich and have access to a Denon Top of the line amp.....

And even then,the amp will only talk to Denon players for doing that purpose.

DVD-A is the most closed format EVER,bar none.

I do keyboards and sounds for bands,and I have access to ALOT of equipment.

And I can't make one either,....from scratch.

If your into the 6 channel format,go DTS or SACD........specifically DTS.

I love SACD(being a DSD fan).....it's closed too....but the stereo mix usually benefits from the remaster too.....

I gave up Hi FI for computers,and I still thank myself for never being interested in DVD-A or SACD really......and that's a shame,because I love audio gear.......and I have a really nice 5.1 system......but I only buy DTS discs.....because that's all I can play....and....It doesn;t use those analog cables....AT ALL.

Only my DIshTV is hooked up analog into my Onkyo.

Sorry for the rant......

BUt I feel even more sorry that DVD-a is staying shut....a waste really.
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Old 9th July 2005, 20:30   #58  |  Link
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No quite impossible. The present rippers will give you the wav files but they still contain the watermark - okay on pcs but cause muting on standalones. It would then be necessary to remove the watermarks from each wave file. This has been done by several 'groups' as a test by identifying the differences between wav files with and without the watermark. I'm not sure if there is an automated programme for removing them but it is possible - read technical papers such as:

"An Attempt on hacking HackSDMI by SnakeByte [ SnakeByte_at_kryptocrew.de ] "

I'm only technically interested in this topic, rather than someone who wants, or owns loads of dvd-audio discs, so can't be bothered to edit the wavs myself or write a programme using the techniques mentioned in the above document.
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Old 9th July 2005, 21:02   #59  |  Link
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So are we saying it's not possible just yet to convert a watermarked multi-channel DVD-A to a multi-channel lossless format... And then if we wanted, back to "un-watermarked" multi-channel DVD-A?


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Old 9th July 2005, 21:23   #60  |  Link
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Quote:
Originally Posted by drmih
<snip> However, when played in a standalone dvd-A player, because of the watermarks, all the functionality is there but when you play a track it either 'mutes' or stops as soon as a watermark is reached.
"Anti-piracy" measures and DRM is more about requiring consumers to buy the compatible hardware ($$$) than protecting copyrights! I won't buy a DVD-A player either!

@bern - agreed! what I will buy is music straight from the musician!
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