Reality check: reading the blu-ray spec. - AVS Forum
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post #1 of 52 Old 03-11-2005, 12:06 PM - Thread Starter
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Since I basically view the BD format as being the ideal (like many here), I thought
I would peruse the BD spec. What can we expect from the first BD discs ?

First, the supported formats at the highest resolution are:

1080@60i, 1080@50i, 1080@24p

So anyone who expects a 60p format (a non-interlaced, 60 cycle), this is not going
to occur. BD is going to back the current broadcast formats (ATSC) as is.

Second, the run length of a mpeg-2, HDTV movie on single layer format is 135 minutes,
or just over 2 hours. The length of a dual layer disc is 3 hours.

Last, the "bonus" length is 2 hours at STANDARD resolution on a single layer disc.

========================

Now, lets examine some of these facts. First, just as for DVDs, the single layer discs are
going to be the prevailing disc that is made for a while after the BD introduction. Just as
for the DVD, this is going to mean that movies will be:

1. Cut down in length for the discs.

2. Shipped on multiple discs.

3. Shipped with "lite" bonus materials.

Again, all of this happened with standard DVDs. The problem ended when dual layer
discs became the norm. But even single layer BDs are going to be hard to manufacture,
so its perfectly reasonable to expect a multi-year delay before dual layer discs appear.

The fact that the spec mentions standard resolution bonus materials I find slightly
disturbing. Here is the most advanced format that is being proposed, and they
clearly envision having NO high defintion bonus materials EVER. Even the MPEG-4
"pie in the sky" part of the spec lists the bonus features as SD.

Lastly, neither BD, nor any other format, is proposing a progressive, 60p format.
This issue seems to be dead on arrival.

==========================

One issue that I predict will occur is related to the dual layer vs single layer nature
of the discs.

If the HD-DVD people are correct about their ease of manufacture, it certainly may
occur that HD-DVD may be made in dual layer format before BD discs appear in
dual layer format.

If this DOES occur, HD-DVD could end up actually having MORE capacity than the
BD for years, even if BD eventually passes the lower capacity format in the long run.

I think this is an important point to remember when "assuming" that BD discs will
have higher capacity/better quality.

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post #2 of 52 Old 03-11-2005, 02:38 PM
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Quote:
Originally posted by samiam95124
So anyone who expects a 60p format (a non-interlaced, 60 cycle), this is not going
to occur. BD is going to back the current broadcast formats (ATSC) as is.
People are looking for 1080p@24 encodings output to 1080p@60 video. Not 1080p@60 encodings.

What purpose does having a 1080p@60 encoding serve if the content is 24fps based?

Gary


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post #3 of 52 Old 03-11-2005, 03:24 PM
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1080i is fine with me, you can't get better than D-Theater tapes, if you can I would like to see it

I am so excited about Blu because I want to record movies from my 169time setup on blank media, also transfer all my d-vhs recording's

bonus features suck :D

-Gary
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post #4 of 52 Old 03-11-2005, 08:38 PM
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Quote:
Originally posted by samiam95124
[b]Since I basically view the BD format as being the ideal (like many here), I thought
I would peruse the BD spec. What can we expect from the first BD discs ?

First, the supported formats at the highest resolution are:

1080@60i, 1080@50i, 1080@24p

So anyone who expects a 60p format (a non-interlaced, 60 cycle), this is not going
to occur. BD is going to back the current broadcast formats (ATSC) as is.
To do 1080i at 60 fps (fields per second) is gonna take a new generation of display hardware. Even the digital cinema system being employed currently don't have that in ther spec, I believe.

However, wanting to go that way is fine as technology eventually improves. I think at 60 frames per second, that's coming close to the way Imax presents their movies. That'll be great, but let's save that for 20 years from now.

Quote:

Second, the run length of a mpeg-2, HDTV movie on single layer format is 135 minutes,
or just over 2 hours. The length of a dual layer disc is 3 hours.

The probably most BD releases won't use MPEG-2. There are two more vudeo codecs to used there, ya know.

Quote:

Last, the "bonus" length is 2 hours at STANDARD resolution on a single layer disc.

I believe using the more advance MPEG-4 codec, you can squeeze in more minutes than 120 of bonus material in SD. You could probably have the bonus in HD too but I'm fine at putting bonus material in HD on a seperate disc.

Having said that, not all of the supplementary materials that were produced for DVDs were recorded on either film or HD format. They could be upconverted to 4:3 HD but it would still be upconverted. I'd rather have something than nothing.


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post #5 of 52 Old 03-11-2005, 11:39 PM
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"Second, the run length of a mpeg-2, HDTV movie on single layer format is 135 minutes,
or just over 2 hours. The length of a dual layer disc is 3 hours.

Last, the "bonus" length is 2 hours at STANDARD resolution on a single layer disc."

Not too sure folks who would buy into either HD optical format care about much else other than the best PQ possible (of the actual MOVIE), in other words it needs to be as good as D-Theater, which has no bonus material at all, notice NO ONE whines about that, some bitch about the player(s), but all love the movies PQ / Audio. Yes I know it's tape, but it's here right now and works, not vapor or terror of any kind.

YMMV........

It is "WOW" TV!
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post #6 of 52 Old 03-12-2005, 12:52 AM
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Here is a link to the Blu-ray technial papers page. The second paper under the BD-ROM section is called the BD ROM - Audio Visual Application Format Specifications. This paper provides all the information on the BD-ROM format not related to hardware. This information does not include the recent audio additions of MLP and Dobly Digital Plus to the format.


Quote:
Originally posted by samiam95124
So anyone who expects a 60p format (a non-interlaced, 60 cycle), this is not going to occur. BD is going to back the current broadcast formats (ATSC) as is.
It would have been nice for Blu-ray to support 1080p at 60 fps but it would have also doubled the cost of the decoder. That is why neither Blu-ray or HD-DVD includes 1080p at 60 fps support. Also Blu-ray does include 720p at 60 fps support.


Quote:
Originally posted by samiam95124
Second, the run length of a mpeg-2, HDTV movie on single layer format is 135 minutes,
or just over 2 hours. The length of a dual layer disc is 3 hours.

Last, the "bonus" length is 2 hours at STANDARD resolution on a single layer disc.
These numbers mean little and using the ATSC data rate of 19.8 Mbps you could fit 5.5 hours of content on Blu-ray. Using MPEG-4 AVC HP or VC-1 at 16 Mbps that could can go up to 7 hours at the best quality possible. Acheiving quality equal to ATSC takes only 8 Mbps with the new video codecs so if you compromise quality to ATSC level you could hold 14 hours of HD content. Granted these estimates do not include lossless audio which could add up to 9 Mbps, but Blu-ray can certainly hold more than 4 hours of HD even with lossless audio on a dual layer disc.


Quote:
Originally posted by samiam95124
Now, lets examine some of these facts. First, just as for DVDs, the single layer discs are going to be the prevailing disc that is made for a while after the BD introduction.
It is expected that dual layer Blu-ray discs will be only slightly more than single layer discs. Unlike DVD we are likely to see many Blu-ray releases that use dual layer discs even within the first year of launch. The main cost of Blu-ray discs will initially be the hard coating and that doesn't change on whether you use one layer or two.


Quote:
Originally posted by samiam95124
Again, all of this happened with standard DVDs. The problem ended when dual layer discs became the norm. But even single layer BDs are going to be hard to manufacture, so its perfectly reasonable to expect a multi-year delay before dual layer discs appear.
Out of curiousty where did you hear this information from? I know much about Blu-ray and some of this sounds unlikely. The latest figures estimate a 99% yield for single layer Blu-ray discs and 92% yield for dual layer discs. To say the least if this can be acheived in the first year of Blu-ray disc manufacturing the price difference between dual layer and single layer discs would be small.


Quote:
Originally posted by samiam95124
The fact that the spec mentions standard resolution bonus materials I find slightly disturbing. Here is the most advanced format that is being proposed, and they clearly envision having NO high defintion bonus materials EVER. Even the MPEG-4 "pie in the sky" part of the spec lists the bonus features as SD.
I am guessing that your talking about page 4 of the BD-ROM physical specs. If so these figures are to say the least old and don't really make much sense today. To say the least many of the HD estimates both from Blu-ray and HD-DVD used SD extras to make it easy for studio executives to understand the numbers. Blu-ray can store 3.5 hours of HD content on a single layer Blu-ray disc (7 hours for dual layer) at the best quality possible.


Quote:
Originally posted by samiam95124
Lastly, neither BD, nor any other format, is proposing a progressive, 60p format. This issue seems to be dead on arrival.
720p at 60 fps is in the Blu-ray specs.


Quote:
Originally posted by samiam95124
If the HD-DVD people are correct about their ease of manufacture, it
certainly may occur that HD-DVD may be made in dual layer format before BD discs appear in dual layer format.

If this DOES occur, HD-DVD could end up actually having MORE capacity than the BD for years, even if BD eventually passes the lower capacity format in the long run.

I think this is an important point to remember when "assuming" that BD discs will have higher capacity/better quality.
Sam, I have to admit I knew you were attacking Blu-ray just from the title of this thread. But to say that Blu-ray won't have dual layer discs ready for years is to put it bluntly a lie. Dual layer Blu-ray discs will be available by next spring which is when Blu-ray is going to launch.
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post #7 of 52 Old 03-12-2005, 01:57 AM
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so what will happen to MPEG-4 AVC/h.264 and VC-1 that the BR specs also support?

These codecs are more efficient than the old mpeg2 which needs lots of bitrate....
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post #8 of 52 Old 03-12-2005, 07:33 AM
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Anything mentioned about 1080p30? That would be reasonable and it is an ATSC format.
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post #9 of 52 Old 03-12-2005, 06:00 PM
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Quote:
Originally posted by Health Nut
Anything mentioned about 1080p30? That would be reasonable and it is an ATSC format.
As of yet I don't think anything has changed in regards to the video rates. Richard Doherty has mentioned a new Blu-ray spec will be released soon so I occasionally check Blu-ray's technical page to see if the BD-ROM Application specs are updated.
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post #10 of 52 Old 03-13-2005, 01:41 AM
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Good comparison link -

http://www.disctronics.co.uk/technology/hddvd/
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post #11 of 52 Old 03-13-2005, 11:31 AM
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Quote:
Originally posted by Richard Paul
It is expected that dual layer Blu-ray discs will be only slightly more than single layer discs.
Minor point: the cost target for any DL disc is 40% over what it costs to manufacture an SL disc...this holds true for DVD, HD-DVD and BD. DVD is obviously there, it looks like HD-DVD is there, and BD will get there.

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post #12 of 52 Old 03-13-2005, 02:09 PM
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Quote:
Originally posted by amillians
Minor point: the cost target for any DL disc is 40% over what it costs to manufacture an SL disc...this holds true for DVD, HD-DVD and BD. DVD is obviously there, it looks like HD-DVD is there, and BD will get there.
One of the only real cost differences between Blu-ray discs and HD-DVD discs is the hard coat that will be put on Blu-ray discs. This hard coat will not change whether the disc is single layer or dual layer. Still it is hard to know for sure since Blu-ray/HD-DVD discs have not been mass manufactured yet.
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post #13 of 52 Old 03-13-2005, 07:37 PM
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Quote:
Originally posted by Richard Paul
...
These numbers mean little and using the ATSC data rate of 19.8 Mbps you could fit 5.5 hours of content on Blu-ray. Using MPEG-4 AVC HP or VC-1 at 16 Mbps that could can go up to 7 hours at the best quality possible. Acheiving quality equal to ATSC takes only 8 Mbps with the new video codecs so if you compromise quality to ATSC level you could hold 14 hours of HD content. Granted these estimates do not include lossless audio which could add up to 9 Mbps, but Blu-ray can certainly hold more than 4 hours of HD even with lossless audio on a dual layer disc.
...
I agree. If one wants to practically discuss the storage capacity of these new disks then it needs to be done in the context of MPEG 4 AVC or VC-1. By the time that these players will finally hit the market it would be inconceivable that these players won't support at least the AVC codec. Especially since the DBS companies have promised implementation of AVC due to their bandwidth constraints faced with having to supply local station HD content. If anything, DBS's AVC push, even on its own in my thinking should cause enough production capacity and interest in AVC to bring it to the price point where it will be cost effective to include it in new high definition DVD players. Maybe if HD-DVD or BD had already come out at this point then talking about AVC would not be relavent but seeing that mass production of these devices is still a ways off, one can not ignore the new codecs and their impact on the new high def DVD's.

Of course this will help not only HD content but SD as well, meaning that with AVC you could store entire seasons of SD TV programs on a single disk without having to ship multiple DVD's of such full-season programs today.
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post #14 of 52 Old 03-14-2005, 07:02 AM
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Richard,

My point was that the manufacturing cost of a DL BD-ROM should be about 1.4x that of a SL BD-ROM...not at first (it will be more than 1.4x), but over time, since if they cost over 1.4x to do, DL will die on the vine. This math applies to HD-DVD as well. I was simply responding to your "slightly more" comment.

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post #15 of 52 Old 03-14-2005, 09:03 AM
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Alex, I think his "slightly more" comment was WRT "its perfectly reasonable to expect a multi-year delay before dual layer discs appear." there is nothing reasonable in that conclusion, DL would need to be at least 2x (and more like 3x and 4x) for that to be a reasonable conclusion. and so 1.4x is slightly more in that respect :)


I think if they need 25-50 it is more reasonable to go 2l then 2 disks even on day one
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post #16 of 52 Old 03-14-2005, 10:58 AM
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What surprised me about HD-DVD is the dual-layer R format. There is none. The only answer for increased capacity for HD-DVD would be the dual-layer RW format, which would costmore.

In terms of pre-recorded movies, that's meaningless. But if you want to archive your HD shows that are bigger than 15GB, you've got no choice in that regard but to go RW.

The HD-DVD group could only counter this negative effect by trying to lower the cost of manufacturing HD-DVD-RW single and dual-layer format.


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post #17 of 52 Old 03-14-2005, 11:17 AM
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Quote:
Originally posted by WriteSimple
The HD-DVD group could only counter this negative effect by trying to lower the cost of manufacturing HD-DVD-RW single and dual-layer format.
The media are coming from conventional manufacturers, so unless the HD-DVD group subsidizes every blank disc, how can they get the price down?

Would they be allowed to subsidize media?

Gary


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post #18 of 52 Old 03-14-2005, 11:33 AM - Thread Starter
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Quote:
Originally posted by WriteSimple
To do 1080i at 60 fps (fields per second) is gonna take a new generation of display hardware. Even the digital cinema system being employed currently don't have that in ther spec, I believe.
My Sony 10wht projector is progressive at 60 (and higher). Thats a 5 year old
projector.
Quote:
The probably most BD releases won't use MPEG-2. There are two more vudeo codecs to used there, ya know.
The Blu-ray group has several times touted the advantages of being able to stay with
mpeg-2, and the spec I read from the BD web site for this article states that again.

The assumption here is that the Blu-ray people mean what they say. This is pretty much the
gist of my posting here, which is "on reading the blu-ray spec, what can we expect".

I want HDTV 'cause I'm nearsighted !
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post #19 of 52 Old 03-14-2005, 11:51 AM - Thread Starter
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Quote:
Originally posted by Richard Paul
[b]
These numbers mean little and using the ATSC data rate of 19.8 Mbps you could fit 5.5 hours of content on Blu-ray. Using MPEG-4 AVC HP or VC-1 at 16 Mbps that could can go up to 7 hours at the best quality possible. Acheiving quality equal to ATSC takes only 8 Mbps with the new video codecs so if you compromise quality to ATSC level you could hold 14 hours of HD content. Granted these estimates do not include lossless audio which could add up to 9 Mbps, but Blu-ray can certainly hold more than 4 hours of HD even with lossless audio on a dual layer disc.
Again, this relies on if the Blu-ray people don't mean what they themselves wrote.
The spec on the BD site clearly says Mpeg-2 will be the first decoder to be used,
and 133 is the single layer play time. I'm sure that "if sony pulls a rabbit out of a hat"
is a cool discussion, but what I posted was "if we read what the blu-ray web site
actually says".

Quote:
It is expected that dual layer Blu-ray discs will be only slightly more than single layer discs. Unlike DVD we are likely to see many Blu-ray releases that use dual layer discs even within the first year of launch. The main cost of Blu-ray discs will initially be the hard coating and that doesn't change on whether you use one layer or two.
I hope you are correct, but respectfully, I doubt it. BD discs are, as admitted by the
Blu-ray group, more difficult to manufacture than current DVDs, and it is clear that
BDs will trail HD-DVDs by a significant margin.
Quote:
Out of curiousty where did you hear this information from? I know much about Blu-ray and some of this sounds unlikely. The latest figures estimate a 99% yield for single layer Blu-ray discs and 92% yield for dual layer discs. To say the least if this can be acheived in the first year of Blu-ray disc manufacturing the price difference between dual layer and single layer discs would be small.

I am guessing that your talking about page 4 of the BD-ROM physical specs. If so these figures are to say the least old and don't really make much sense today.
As my original post said, I speculated that dual layer production will be sometime
after single layer, because that is what happened with DVDs. If there is some magic
that allows dual layer and single layer to happen at the same time, thats great.

However, there is no reason to expect that, nor does the Blu-ray site say that. They
just said they could test manufacture the dual layer discs. "can make" does not
equal "is cheap to make".

I want HDTV 'cause I'm nearsighted !
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post #20 of 52 Old 03-14-2005, 12:25 PM
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Quote:
Again, this relies on if the Blu-ray people don't mean what they themselves wrote.
The spec on the BD site clearly says Mpeg-2 will be the first decoder to be used,
and 133 is the single layer play time. I'm sure that "if sony pulls a rabbit out of a hat"
is a cool discussion, but what I posted was "if we read what the blu-ray web site
actually says".
1) since all three codecs are required for the player whomever makes the decision on the movie has the last say not the BR group no matter what they want

2) the original BR spec only had MPEG-2, how old is that info you are looking at? if it was before they added the other two then that might be the reason.

3) MPEG-2 is the worst of all three codecs, so it works well as a limitting factor


Quote:
I hope you are correct, but respectfully, I doubt it. BD discs are, as admitted by the
Blu-ray group, more difficult to manufacture than current DVDs, and it is clear that
BDs will trail HD-DVDs by a significant margin.
no one knows and there is nothing clear about it, but what does it even havce to do with the market for SL/DL BR disks?
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post #21 of 52 Old 03-14-2005, 03:34 PM
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Quote:
Originally posted by amillians
My point was that the manufacturing cost of a DL BD-ROM should be about 1.4x that of a SL BD-ROM...not at first (it will be more than 1.4x), but over time, since if they cost over 1.4x to do, DL will die on the vine. This math applies to HD-DVD as well. I was simply responding to your "slightly more" comment.
I understand your point and in truth I do not know how dual layer Blu-ray discs will cost compared to single layer since neither have been mass manufactured yet. Out of curiosity where did you get the 1.4x number from? Also isn't the difference between dual layer and single layer DVD less than that now?


Quote:
Originally posted by WriteSimple
What surprised me about HD-DVD is the dual-layer R format. There is none. The only answer for increased capacity for HD-DVD would be the dual-layer RW format, which would costmore.
At the moment dual layer HD-DVD-RW is not a possibility considering the cost of the laser needed. The problem is that a HD-DVD-RW writer needs ten times the laser power to write dual layer discs compared to a dual layer Blu-ray writer. Because of that a dual layer HD-DVD-RW laser would currently cost over $10,000. The DVD Forum understands that it would be a publicity advantage for Blu-ray so they have no current plans to make a dual layer HD-DVD-RW format.


Quote:
Originally posted by samiam95124
The Blu-ray group has several times touted the advantages of being able to stay with mpeg-2, and the spec I read from the BD web site for this article states that again.

The assumption here is that the Blu-ray people mean what they say. This is pretty much the gist of my posting here, which is "on reading the blu-ray spec, what can we expect".
It will be the studios that will decide what video/audio codecs to use. Basically your seeing the worse that can be done with the format and using that as an example. It would be like me looking at the DVD Forum articles about using red laser HD-DVD, which is basically a DVD using the new video codecs, and saying that is what HD-DVD will be. Both formats can look great if they are done well but both can look bad if they are done poorly. The reason I support Blu-ray is that it has a greater potential than HD-DVD.


Quote:
Originally posted by samiam95124
Again, this relies on if the Blu-ray people don't mean what they themselves wrote. The spec on the BD site clearly says Mpeg-2 will be the first decoder to be used, and 133 is the single layer play time. I'm sure that "if sony pulls a rabbit out of a hat" is a cool discussion, but what I posted was "if we read what the blu-ray web site actually says".
Where does it say that MPEG-2 will be the first decoder to be used? Also once again I would recommend reading the BD-ROM specs which may answer many of your questions. BD-ROM can use MPEG-2, MPEG-4 AVC HP, and VC-1 for video along with Dolby Digital, Dolby Digital Plus, Doby Digital Lossless (formerly called MLP), DTS, DTS-HD Lossy, DTS-HD Lossless, and PCM for audio. Both Blu-ray and HD-DVD have the exact same video/audio codecs.


Quote:
Originally posted by samiam95124
I hope you are correct, but respectfully, I doubt it. BD discs are, as admitted by the Blu-ray group, more difficult to manufacture than current DVDs, and it is clear that BDs will trail HD-DVDs by a significant margin.
So was DVD when it came out and now it is cheap and easy to manufacture. Believe it or not this format war is very similar to the DVD format war with SD and MMCD. If this turns out the same way then Blu-ray will win.


Quote:
Originally posted by samiam95124
As my original post said, I speculated that dual layer production will be sometime after single layer, because that is what happened with DVDs. If there is some magic that allows dual layer and single layer to happen at the same time, thats great.
The difference between now and then is that layer bonding is now a very well understood procedure, while back when DVD first came out it was very new. Granted the disc structure of Blu-ray is different then DVD, but the procedure to bond multiple layers is the same. Why then you do believe that it will be hard to do? What information makes you believe that it will be harder to bond two Blu-ray layers then two DVD layers?


Quote:
Originally posted by samiam95124
However, there is no reason to expect that, nor does the Blu-ray site say that. They just said they could test manufacture the dual layer discs. "can make" does not equal "is cheap to make".
At the moment they are test manufacturing both single layer and dual layer Blu-ray discs. Actual manufacturing will begin this fall and by spring we should begin to know how much it will cost to manufacture Blu-ray discs.
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post #22 of 52 Old 03-14-2005, 04:34 PM
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Quote:
Originally posted by Richard Paul
At the moment dual layer HD-DVD-RW is not a possibility considering the cost of the laser needed. The problem is that a HD-DVD-RW writer needs ten times the laser power to write dual layer discs compared to a dual layer Blu-ray writer.
I've heard the laser power is the reason they are only talking about single-layer HD-DVD-R. But, does it hold for HD-DVD-RW (the claim is 32GB dual layer is under development)?

If it is 10x for RW, then "never-gonna-happen" comes to mind.

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post #23 of 52 Old 03-15-2005, 10:52 AM - Thread Starter
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Quote:
Originally posted by AnthonyP
[b]1) since all three codecs are required for the player whomever makes the decision on the movie has the last say not the BR group no matter what they want
Where did you see "all three codecs are required" ?
Quote:

2) the original BR spec only had MPEG-2, how old is that info you are looking at? if it was before they added the other two then that might be the reason.
The spec mentions mpeg-4, but several times mentions the "advantage" of having
BD use mpeg-2.
Quote:
3) MPEG-2 is the worst of all three codecs, so it works well as a limitting factor
Well, I would put that "mpeg-4 is the best of all codecs", since it is completely
compatible with mpeg-2.

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post #24 of 52 Old 03-15-2005, 11:01 AM - Thread Starter
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Quote:
Originally posted by Richard Paul

The difference between now and then is that layer bonding is now a very well understood procedure, while back when DVD first came out it was very new. Granted the disc structure of Blu-ray is different then DVD, but the procedure to bond multiple layers is the same. Why then you do believe that it will be hard to do? What information makes you believe that it will be harder to bond two Blu-ray layers then two DVD layers?

At the moment they are test manufacturing both single layer and dual layer Blu-ray discs. Actual manufacturing will begin this fall and by spring we should begin to know how much it will cost to manufacture Blu-ray discs.
The one thing that everone agrees on is that the BD process is going to be different, and
initially more difficult than, standard DVD. Right now, there is no BD shipping. Also,
DVDs are made widely now. You can pick up the required equipment on EBAY
(no, I am not kidding. Injection molding machines specifically designed to produce
CDs and DVDs appear on occasion). What happens in Sony labs does not immediately
ripple outwards.

Now what you appear to be saying is that anyone making a BD format will have no
incentive to produce SL discs instead of DL discs. I respect that opinion, I simply
believe there is every reason to think that, with a difficult new process as BD is,
producing a SL disk first is a perfectly reasonable thing to do.

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Where did you see "all three codecs are required" ?
for the players. It was mentioned all over the place try http://www.blu-raydisc.com/assets/do...0305-12955.pdf in section 3.3

Quote:
The spec mentions mpeg-4, but several times mentions the "advantage" of having
BD use mpeg-2.
where what?


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Well, I would put that "mpeg-4 is the best of all codecs"
until we have some video from all 3, Mpeg-2, AVC HP and VC-1 I don't think anyone knows what is the "best" also one might be better then others in different ways. It is known that AVC and VC1 is more efficient, but does it give something to get it?

Quote:
since it is completely
compatible with mpeg-2.
can't see why that is important
why is that
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The thing is, any arguments concerning BD-ROM production really point to a harmed by massive success scenario.

Initially neither BD-ROM nor HD-DVD will require sufficient manufacturing capacity to be a problem.

Pioneer and Sony made LDs.
JVC makes DTheater tapes.
Sony could manufacture all the BD-ROM required for several years.

It's an if and when a format takes off, and the production costs become an important issue. Then you have the capital cost of installing BD-ROM production versus the ease of flipping a current DVD production machine over to HD-DVD.

If (and I believe it is still a big if) PS/3's come with BD-ROM drives, then all the serious production capacity needed for movies is already in place for the games (games >>> movies).

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post #27 of 52 Old 03-15-2005, 12:40 PM
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Quote:
The one thing that everone agrees on is that the BD process is going to be different, and
initially more difficult than, standard DVD.
agree, but why is it important? do you build a standard on today or what you can do with it? if it is only today, then DVD is cheapest so why HD-DVD or BR. BR has the most potential for the future and the production advantage of HD-DVD could be short lived.


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Right now, there is no BD shipping.
there is no HD-DVD shipping either, and to be picky BD has been shipping for some time it is just preproduced BD-rom that has not
Quote:
Also,
DVDs are made widely now. You can pick up the required equipment on EBAY
(no, I am not kidding. Injection molding machines specifically designed to produce
CDs and DVDs appear on occasion).
but HD-DVD is not the same as DVD it is close but not the same

Quote:
Now what you appear to be saying is that anyone making a BD format will have no
incentive to produce SL discs instead of DL discs. I respect that opinion, I simply
believe there is every reason to think that, with a difficult new process as BD is,
producing a SL disk first is a perfectly reasonable thing to do.
no, I think what he is saying is that BD DL will not have as big a disadvantage as you think. I think they will both exist and used like today with DVD depending on what is needed
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post #28 of 52 Old 03-16-2005, 03:02 AM
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Quote:
Originally posted by samiam95124
Well, I would put that "mpeg-4 is the best of all codecs", since it is completely compatible with mpeg-2.
When they talk about MPEG-4, it is part 10, also known as H.264. Not related to MPEG-2 at all.

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post #29 of 52 Old 03-16-2005, 03:19 AM
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Quote:
Originally posted by Richard Paul
Richard Doherty has mentioned a new Blu-ray spec will be released soon so I occasionally check Blu-ray's technical page to see if the BD-ROM Application specs are updated.
It's up there now. The redline version showed the only changes were adding the new audio codecs.

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When they talk about MPEG-4, it is part 10, also known as H.264.
and AVC
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