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Quote:
Originally Posted by tzucc
what are the video codecs for HD DVD and Bluray?
I haven't kept up with the latest information, but the last I heard was:


MPEG2

MPEG4

H.264

VC-1


John is probably more up to speed on this though.
 

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Quote:
Originally Posted by amillians
Some clarifications...


Neither the Sony nor the Pioneer BD deck has onboard decoding for anything beyond DD/DTS. Unofficially, they can pass DD+ and lossy DTS-HD MA over HDMI (both are HDMI 1.2a compliant);
Technically speaking, this is out of spec, since DTS-HD (to lossless) is a mandatory part of the Blu-ray Audio specs.


Quote:
it's HDMI 1.3 that's necessary for passing DTHD (AKA Lossless Dolby) and lossless DTS-HD MA streams.
Streams yes.


I'm incredibly disappointed that everyone is falling flat on their face and not doing lossless PCM output over HDMI. DTS and Dolby were touting this as a great feature of the new codecs for initial compatibility with HDMI 1.1 equipped receivers.


Quote:
Pioneer seems more adventurous in doing whatever is necessary to support the unofficial passing of DD+ and lossy DTS-HD MA...Sony is playing it safe.
Sony is staying in spec for HDMI, Pioneer is not. So if it doesn't work it's aggravating, frustrating etc etc etc and in the hand out of spec.


Never mind that there's nothing to pass this to yet, and I'm not sure how they're going to get around this interoperation issue with the various HDMI levels.


Following specs is how you get interoperation to work on a large scale (think Ethernet, the 802.11 family of protocols etc).

Quote:
That said, the Sony is capable of extracting the legacy streams (using simple profile decoders) of the new codecs, as available (e.g., although it can't decode DD+, it can ferret out the IS0 core DD 5.1 stream if DD+ encoding was used).
That's actually part of a DD+ decode, the ability to output a DD stream. Perhaps this is a semantic distinction?

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The specs on the Toshiba decks were apparently altered at the last minute to note that DTS-HD decoding is *only* for the core DTS 5.1 stream.
That's not clearly documented in available specs. Where are you getting the information from?

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I would argue this violates the HD DVD spec, but apparently it doesn't.
I'm disappointed for a number of reasons, including the lack of full Dolby TrueHD support.


Add the (apparent) lack of support for DTS-HD in lossless mode and you're talking about a major failure vs. the promise of the format.

Quote:
This "issue" is still kind of up in the air...how the A1/XA1 actually "decode" DTS-HD is still the subject of much debate (e.g., is it an actual full decode, or just a partial decode of the core a la DD+ simple decoding of the core?).
DTS-HD specs state that the output from even a lossless stream in the decoder can be a std DTS 1.5 Mbit output via S/PDIF in addition to lossless PCM on HDMI 1.1 (or higher) and D/A of that stream and output via analog.

Quote:
Lossless DTS-HD MA maxes out at a whopping 24.5Mbps VBR as spec'd for Blu-ray.


Blu-ray supports (optional in the player) 27.648Mbps CBR LPCM.
Realistically speaking, we will never see discs at these rates with LPCM. 27.6 Mbits/second equates to 6x 24/192K.

Quote:
In-player decoding is the only way to take advantage of the new audio codec mixing features as well as the new format interactive features (e.g., menu button sounds, etc.). DD+, for example, supports up to 8 independent substreams...and they can be mixed willy nilly if so authored (e.g., director's commentary in substream IS1 is mixed into the main IS0 track). The days of passing raw unencoded streams to pre/pros or AVRs--assuming disc authors take advantage of the new capabilities--might be coming to a close...as Michael noted, LPCM via HDMI is the "right" way to handle audio for both formats. Whether audiophiles adapt to the new world order, though, remains to be seen. :)
You won't see me arguing about that. I've owned DVD-Audio players for 4 years now that handle decoding in player, then pass the decoded PCM streams down to the processor.


It allows you to cut down on the amount of DSP horsepower in the processor and get solutions to market faster.


Cheers,
 

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Quote:
Originally Posted by Mr.Poindexter
I haven't kept up with the latest information, but the last I heard was:


MPEG2

MPEG4

H.264

VC-1


John is probably more up to speed on this though.
More specifically, it's MPEG-4/AVC which is based in part on H.264. I think H.264 might be part of VC-1 too, but I haven't studied the guts of that spec.


So drop H.264 from the list and you're spot on.


Regards,
 

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Quote:
Originally Posted by Mr.Poindexter
John, I was unaware that BluRay was 48 Mbit. While I am not assuming that 22MBit MPEG2 is better than 14 Mbit VC-1 or MPEG4, I am just thinking in terms that I am familiar with. I haven't worked with MPEG4 enough to know what rates I would need to be satisfied with the results. I do know that I never complain about having too high a bit rate when it comes to final image quality.
There are two portions to bit rates anyway, average and peak.

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I do know of some production that is planned to be mastered in 24/96 for a special anamorphic HD project but I agree that Hollywood isn't about to send us the best quality yet.
Right. Note that this is outside the realm of std movie production channels.


In defense of the movie studios, they deliver the best that they can with the equipment they have. They have significant expense in their 48K infrastructure and it's going to cost more than a few $$$ to replace all the gear with 96K in the staging and scoring studios. I haven't even talked about location work yet.


Regards,
 

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Quote:
Originally Posted by ChrisWiggles
Yes, that's my point, but that hinges on a non-fixed bitrate. You can't take advantage of that in a plain DD/DTS environment because they have fixed bitrates, so when there's not much going on you're wasting data. I don't see how this can be taken advantage of in a fixed-bitrate encode at all.
I haven't gotten into this level of the codecs, but it is possible to take advantage of this in a fixed rate environment by marking channels with no data as null and reusing the bits for channels that have activity.


Whether it works this way with the actual codecs or not, I can't say.
 

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John what do you make of the Thomas Norton comments on the HDMI,"A recent listen to two-channel stereo via HDMI did not impress me; it sounded noticeably inferior to a standard coaxial digital connection." Care to speculate as to what's happening? Any first hand experience with HDMI and audio? Do you think there is any validity to the statements that HDMI does not "sound good." I'm baffled as to why an HDMI connection would be inferior to the coax. I've been told that it has something to do with audio being tied to the video clock or whatever that means? I have no idea. http://ultimateavmag.com/news/032106sonylineshow/
 

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Quote:
Originally Posted by John Kotches
I haven't gotten into this level of the codecs, but it is possible to take advantage of this in a fixed rate environment by marking channels with no data as null and reusing the bits for channels that have activity.


Whether it works this way with the actual codecs or not, I can't say.
I could understand that, I just don't know of any soundtracks where a channel completely cuts out. Anyway, my point was just that with a non-fixed bitrate, the newer iterations off DD and DTS, either lossy or lossless, will allow for much more efficient storage, so we should be able to get (just like with the video) the same quality we get now with less data, or better quality with the same data rates as now, and even way better with higher data rates of course.
 

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Quote:
Originally Posted by John Kotches
More specifically, it's MPEG-4/AVC which is based in part on H.264. I think H.264 might be part of VC-1 too, but I haven't studied the guts of that spec.


So drop H.264 from the list and you're spot on.


Regards,
Mpeg4/AVC/H.264 are all commonly used interchangeably. I see H.264 used more often though. This is not related to VC-1.
 

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Alex,
Quote:
Pioneer seems more adventurous in doing whatever is necessary to support the unofficial passing of DD+ and lossy DTS-HD MA
No surprise there. My first DVD player was a Pioneer, which passed a 96/24 signal from its S/PDIF outputs. I'm sure Pioneer was breaking some rules there, as other players back then all padded down the signal to 48/24 for their digitial outs. Nice to see they're still rebels.


BTW, thanks for your post. As informative as it was, by the end I was frustrated by what a mess of inconsistent specs the situation was. If either of these delivery formats catch on with the general public, I'll be amazed.


Sanjay
 

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I'll be checking out whatever solution Meridian has with regard to these new formats. I want it done right though. I agree with those saying the decoding s/b done in the players, with the gain and bass mgmt, room correction, et al done in the pre/pro.


But I really think the bottom line right now is to see how this shakes out for a year or so.
 

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Quote:
Originally Posted by ChrisWiggles
I could understand that, I just don't know of any soundtracks where a channel completely cuts out. Anyway, my point was just that with a non-fixed bitrate, the newer iterations off DD and DTS, either lossy or lossless, will allow for much more efficient storage, so we should be able to get (just like with the video) the same quality we get now with less data, or better quality with the same data rates as now, and even way better with higher data rates of course.
Chris,


I'll have to check out a few when I have some time. There's not a lot of free time right now as we're moving in two weeks ;)


One I'm pretty sure that will do just that is Good Night, and Good Luck.
 

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Quote:
Originally Posted by Bulldogger
John what do you make of the Thomas Norton comments on the HDMI,"A recent listen to two-channel stereo via HDMI did not impress me; it sounded noticeably inferior to a standard coaxial digital connection." Care to speculate as to what's happening?
I don't make much of it at all. I prefer forming my own opinions :)


Quote:
Any first hand experience with HDMI and audio?
Not yet. I've had difficulty getting HDMI DVD players and receivers together at the same time.


My reference receiver for the 2nd system (Denon AVR-4306) has the capability but nothing's come through with HDMI audio out that I've been able to work with yet.

Quote:
Do you think there is any validity to the statements that HDMI does not "sound good." I'm baffled as to why an HDMI connection would be inferior to the coax. I've been told that it has something to do with audio being tied to the video clock or whatever that means? I have no idea. http://ultimateavmag.com/news/032106sonylineshow/
No experience yet, so I can't say. The data is passing across an encrypted link if HDMI is invoked, which means you have to buffer to decrypt at which point you can easily reclock to get very low jitter.


Regards,
 

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Quote:
Originally Posted by John Kotches
Chris,


I'll have to check out a few when I have some time. There's not a lot of free time right now as we're moving in two weeks ;)


One I'm pretty sure that will do just that is Good Night, and Good Luck.
Interesting. I could see that to be the case on a film like this one. I had never heard this as a possibillity though, as this would be different than say going to 1.0 DD which would dedicate everything to one channel (or fewer than 5.1). In any case, this advantage should be hugely beneficial to increase the efficiency of bit allocation in the newer formats.
 

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Quote:
Originally Posted by John Kotches
Technically speaking, this is out of spec, since DTS-HD (to lossless) is a mandatory part of the Blu-ray Audio specs.
Not the BDA specs I have seen. :)


Mandatory BD player decoding is DD 5.1 640Kbps and DTS 5.1 1.524Mbps. PCM is along for the ride, 18.432Mbps player mandatory, with 27.648Mbps 6 x 192/24 player optional.


DD+ up to 4.736Mbps, Dolby Lossless up to 18.64Mbps, DTS-HD MA lossy up to 24.5Mbps lossless are player optional.


That was the message screamed loud and clear at the last BDA Japan event, along with secondary streams having to be DD+ (5.1 48/24 256Kbps max) or DTS-HD LBR (5.1 48/24 256Kbps max), but decoding there is optional.


I think this mandatory/optional breakdown is one area where Sony really painted their whole team into a corner...they planned on 50GB DL to be readily available day one, so LPCM was their answer on the high end audio front. Time to pay that piper, and MPEG-2 encoding isn't helping their cause. I can only hope that full-on player decoding solutions prevail in short time if 50GB remains somewhat elusive...it seems silly to devote that many bits to uncompressed audio.

Quote:
Originally Posted by John Kotches
Never mind that there's nothing to pass this to yet...
Panasonic pre-announced the SA-XR700 AVR at a recent roadshow, which Panny hopes dealers will sell as a package with the DMP-BD10 BD deck come September, for an "end-to-end" solution in audio. It's implied it's HDMI 1.3, with DD+, DTHD/Lossless and DTS-HD MA decoding onboard...but that's not confirmed. No price yet, and no specs. Just hints.

Quote:
Originally Posted by John Kotches
That's actually part of a DD+ decode, the ability to output a DD stream. Perhaps this is a semantic distinction?
Very much so. When discussing "output" there's a fine line between "extraction" and "ignore," and it differentiates (in theory) the two optical formats.

http://www.avsforum.com/avs-vb/showt...&post7378358


(excuse the rambling...I was on a journey of discovery, apparently involving peyote)

Quote:
Originally Posted by John Kotches
That's not clearly documented in available specs. Where are you getting the information from?
A lame disclaimer started to appear in their ads and marcom recently, noting that for the XA1 and A1, there was "DTS-HD support for up to 5.1 channels of DTS core only." That's not decoding in my book, that's ignoring, a la a simple DD+ IS0 AC-3 grab. Boo...this is what the Sony deck does with DTS-HD MA. I still can't accept it as fact, though...I just don't want to. :)
 

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Alex,


I don't like the way this is working out at all.


Paper tiger, real life lamb from an audio perspective.
 

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Quote:
Originally Posted by amillians
Not the BDA specs I have seen. :)


Mandatory BD player decoding is DD 5.1 640Kbps and DTS 5.1 1.524Mbps. PCM is along for the ride, 18.432Mbps player mandatory, with 27.648Mbps 6 x 192/24 player optional.


DD+ up to 4.736Mbps, Dolby Lossless up to 18.64Mbps, DTS-HD MA lossy up to 24.5Mbps lossless are player optional.


That was the message screamed loud and clear at the last BDA Japan event, along with secondary streams having to be DD+ (5.1 48/24 256Kbps max) or DTS-HD LBR (5.1 48/24 256Kbps max), but decoding there is optional.
There idea of mandatory and my idea of mandatory are somewhat different. DTS-HD was supposed to be mandatory support in Blu-ray. All of the optionals are lossless.


Using LPCM (right now it's 20/48 and 24/48 for films) is very problematic for a 25GB disc or a 50GB disc. At the above rates we're talking about a max of ~9.2Mbits/second (7.1) or 1.15 Megabytes/second (base 10 for easy disc math). If we have a movie with a running time of 120 minutes, we're talking about ~8 GB of the total available 25GB on a single layer. Double the sampling rate and you've doubled the space requirements.


It simply is not practical to use LPCM on movie soundtracks. Could you imagine using 6 channels of 24/192K? Ay chihuahua. That's one layer of a dual layer disc just for audio.


Not good. Not good at all.


Politics aside, it's clear that the practical implementation of lossless audio (and LPCM is lossless ;) ) will require either of the HD codecs for audio.

Quote:
I think this mandatory/optional breakdown is one area where Sony really painted their whole team into a corner...they planned on 50GB DL to be readily available day one, so LPCM was their answer on the high end audio front. Time to pay that piper, and MPEG-2 encoding isn't helping their cause. I can only hope that full-on player decoding solutions prevail in short time if 50GB remains somewhat elusive...it seems silly to devote that many bits to uncompressed audio.
Don't you just love Sony for this type of stuff? See above.

Quote:
Panasonic pre-announced the SA-XR700 AVR at a recent roadshow, which Panny hopes dealers will sell as a package with the DMP-BD10 BD deck come September, for an "end-to-end" solution in audio. It's implied it's HDMI 1.3, with DD+, DTHD/Lossless and DTS-HD MA decoding onboard...but that's not confirmed. No price yet, and no specs. Just hints.
I'll see if my contact at Silicon Images can pass along some info. No guarantees of anything.


Quote:
A lame disclaimer started to appear in their ads and marcom recently, noting that for the XA1 and A1, there was "DTS-HD support for up to 5.1 channels of DTS core only." That's not decoding in my book, that's ignoring, a la a simple DD+ IS0 AC-3 grab. Boo...this is what the Sony deck does with DTS-HD MA. I still can't accept it as fact, though...I just don't want to. :)
I haven't seen the ads, then again my area is a high-tech hotbed :D
 

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Quote:
Originally Posted by Michael Grant
First of all: HD-DVD is 36Mbps max, but Blu-Ray is 48Mbps. Blu-Ray has a bit of an advantage there. Secondly, even if we grant your 15Mbps number, that leaves 21/33Mbps for video. For next-gen video codes (VC-9,H.264), that's more than enough; MPEG-2 might be a bit dicey at 21Mbps, but that's where Blu-Ray's higher bandwidth may come in handy.

[...]

Overall, I'd have to say I'm not too worried about high-quality audio eating into video quality---particularly if a next-gen video codec is used.
Michael --

IIRC, our beautiful OTA ATSC maxes out at 19.8 Mb/s, including a DD soundtrack (I can't check bitrates easily, but I believe it's mostly 384 or 448 Kb/s). I wouldn't call MPEG-2 at 21 Mb/s "dicey" unless you're looking for substantially better than HDTV quality.


Of course, there are some artifacts in (compressed) HDTV, so maybe we really do need a higher bitrate....


Drew Dean
 

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Quote:
Originally Posted by ddean
Michael --

IIRC, our beautiful OTA ATSC maxes out at 19.8 Mb/s, including a DD soundtrack (I can't check bitrates easily, but I believe it's mostly 384 or 448 Kb/s). I wouldn't call MPEG-2 at 21 Mb/s "dicey" unless you're looking for substantially better than HDTV quality.
I can't speak for Michael on his target PQ, but for me the lowest acceptable level is D-VHS level of quality.

Quote:
Of course, there are some artifacts in (compressed) HDTV, so maybe we really do need a higher bitrate....
The locals vary widely in PQ, often depending on subchannels running.


Also ~20 Mb/s is the maximum in the spec, it is not a CBR delivery. DD is 384K to minimize soundtrack footprint.
 

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Quote:
I wouldn't call MPEG-2 at 21 Mb/s "dicey" unless you're looking for substantially better than HDTV quality.
Then "dicey" it is.
 
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