Talk:Blu-ray

Wavelength - Disk space

If infrared has a wavelength of 650 nm and violet has 405 (60% shorter) then how would that permit 21 more gigabytes to fit? Shouldn't the number be 7.5? What am I miscalculating?--Spectatorbot13 (talk) 13:57, 11 April 2009 (UTC)

You are calculating incorrectly. First, take 4-inch ruler that is long enough to hold four one-inch-long one-dimensional objects. How many half-inch-long one-dimensional objects can it hold? Now take 4-inch by 4-inch sheet of paper large enough to hold 16 one-inch-square two-dimensional objects. How many half-inch-square two-dimensional objects can it hold? (There are other changes as well, so the above is just a starting point for your calculations, but you do need to start with two-dimensional density calculations, not one-dimensional.) 72.251.90.229 (talk) 21:12, 26 July 2009 (UTC)

To put it more succinctly -- you're calculating by length, not area. A smaller laser spot makes possible not only more information along the track, but more-closely spaced tracks. The areal density of information varies roughly as the inverse square of the wavelength. WilliamSommerwerck (talk) 23:13, 23 October 2009 (UTC)

"Six times more..."

The introductory text says,

The name Blu-ray Disc refers to the "blue laser" used to read the disc, which allows for six times more storage than on a DVD.

If it offers six times more, then it offers seven times as much; correct? "More than" means "in addition to what already exists"; true? I'm still in the early stages of learning about Blu-Ray, and don't yet know the numbers. "Times more" and "times less" seem to be a very popular, but logically-sloppy shorthand that shouldn't be in an encyclopedia, where strict language is especially significant. For instance: A three-yard-wide fence (or, make that three meters long) is two yards/meters wider than a one-yard/meter fence, right? That would make it two times wider. (To lessen obfuscation, I'll use "yards" only from here on.)

When writing (or editing), in particular, please carefully avoid "times smaller" or the equivalent! It's appropriate for describing the smile of the Cheshire Cat, provided the numbers are right (two times smaller than the cat's face), but "times smaller" and such typically leads to logical absurdity. The one-yard fence is not three times smaller (or narrower) than the three yard fence. It is, however, one-third the width of the three-yard fence. In more detail, the narrow fence is two yards narrower. If you say it's three times narrower, then "times" implies multiplication. Multiplication of what? The width of the three-yard fence, of course. Three times that is nine yards. If it's nine yards smaller, it's minus six yards wide! This suggests that the fence has been obliterated, leaving a double-size negative ghost image.

Regards, Nikevich (talk) 15:52, 17 November 2010 (UTC)

8-bit or 10-bit color depth

Is Blu-Ray video 8-bit or 10-bit in color depth? I could not find this info anywhere. DORC (talk) 12:07, 20 April 2009 (UTC)

A Blu-ray disc can store 10-bit color depth but it depends of the panel of your TV and your blu-ray player. —Preceding unsigned comment added by 201.78.42.31 (talk) 12:19, 20 July 2009 (UTC)

What is the 12-bit per component so-called "deep colour" that's offered by many (even budget priced) Blu-Ray players around at the moment? I doubt that the information exists on the disc as the highest quality HD recording format I know of (HDCAM SR) only records with 10-bit precision and most of the lesser formats only record with 8-bits of precision, and that includes most of the file-based, as well as tape-based, recording systems. I suspect therefore that it's a bit of a con, rather like the 20-bit and 24-bit DACs used by some CD player manufacturers. MegaPedant (talk) 09:15, 30 November 2009 (UTC)

Attacks on the DRM

"The first known attack relied on the trusted client problem. In addition, decryption keys have been extracted from a weakly protected player (WinDVD)". Please explain what an attack relying on the "trusted client problem" is, and what's the difference is between that and extracting keys from a PC software (WinDVD). Unless somebody can add more info I suggest we change this. Has any attack relied on something else than extracting single device keys from software or hardware players? -- LM, 6 June 2009. —Preceding unsigned comment added by 213.100.57.46 (talk) 18:54, 4 June 2009 (UTC)

The program DumpHD, along with some supporting software is known to cirumvent versions of the BD+ protection. Read main article for more (citated) information! ("BD+" section)

Removed some un-cited marketing propaganda found in the article

From the BluRay article

". This technology enables content and service providers to offer value-added interactive features that can be initiated and managed by consumers via their disc player remote control directly from their living rooms "

Needless to say, this is un-necessary and un-cited marketing propganda (propably inserted there by the marketing dept of the BluRay Disc assosiation. Especially the "via their disc player remote control directly from their living rooms" part, is pure marketing language, full of misleading content (you don't have to have a remote control or to be in your living room, you can do it from a PC in your bedroom), and generally, it is not of encyclopedic content in any way. Improved with facts (someone to add a citation, too). —Preceding unsigned comment added by 195.130.121.48 (talk) 07:37, 18 June 2009 (UTC)

Also, added some improvements to the "BD+" —Preceding unsigned comment added by 195.130.121.48 (talk) 07:40, 18 June 2009 (UTC)

Greetings, and thanks for your contributions, I agree with your position on the marketing lingo in the article. However, you made about 10 consecutive edits in one day. I don't mean to be a dick, but Wikipedia policy discourages more than 3 edits per day so try to make up your mind on what you want to edit in the article and do it all in one edit, then if you forget something you edit again. Making too many minor edits is considered counterproductive and a waste of bandwidth.--Spectatorbot13 (talk) 14:48, 18 June 2009 (UTC)

Speaking of marketing propaganda, whats about the "PLAYSTATION®3", with registered trademark, all caps and everything, doesn't look too neutral to me. 62.107.158.115 (talk) 23:30, 24 June 2009 (UTC)

You are right. Obviously, these guys at the BluRay Disc Association are suffering from the "EA syndrome". EA Syndrome: The act of "improving" encyclopedic articles referring to your company, by removing the unfavorable parts, inserting marketing language full of ambiguous sentences and shoving trademarked buzzwords all over the place.—Preceding unsigned comment added by 195.130.121.48 (talk • contribs) 06:03, 7 July 2009

Wrong URL

When searching bluray disc in google or even in wikipedia's built in search this link is returned as the best result: http://en.wikipedia.org/wiki/Blu-ray_Disc Also this very article's link points to this link. Sadly this link only shows a 404 not found error. Is there a way to make it redirect to this article?

The the correct URL seems to be: http://en.wikipedia.org/wiki/Bluray_Disc

--200.115.64.250 (talk) 16:50, 28 October 2009 (UTC)

Region code map errors / inconsistencies

I changed the world-map image for the "Region Codes" section from "Blu-ray regions with key.png" to "Blu-ray regions without key.png". The "...with key.png" image shows incorrect information for some countries according to the reference map on the Blu-ray Disc Association web site (BDA FAQ link).

The Blu-ray Disc Association (BDA) web site provides only very general information on which countries "belong" to which BD region codes. However, the BDA does provide a low-resolution, color coded map of the world showing the three regions - A, B and C - and from this map one can identify the correct BD region for most countries.

A (previously used?) wikipedia map already exists in wiki commons that is more correct / more consistent with the BDA web site information so I have changed the article to link to that more correct image ("Blu-ray regions without key.png").

The areas of "Blu-ray regions with key.png" that were inconsistent with the BDA map include:

• Papua New Guinea: BDA map indicates Papua New Guinea is Region 'B' like its neighbor Australia, not Region 'A' like its neighbor Indonesia
• French Guiana: The BDA map indicates French Guiana is Region 'B', unlike its South American neighbors which are all Region 'A'
• Belarus: The BDA map indicates Belarus is Region 'B' not 'C'
• Ukraine: The BDA map indicates Ukraine is Region 'B' not 'C'

There appears to be one small error remaining in the new map but I don't have the graphic editing tools necessary to fix it:

• Although not unambiguously marked on the BDA map, the small, non-contiguous part of Russia (the part 'sandwiched' between Lithuania and Poland) presumably is Region 'C' (Russia), not 'B' (Rest-of-Europe)

This issue has been discussed before (Talk:Blu-ray_Disc/Archive_9#Inconsistency_in_region_code_map) and there appear to be a lot of incorrect maps "out there". Of course it is possible that the BDA map itself is incorrect - but unless someone can find a more reliable / authoritative source for region-code information, this BDA map seems to be the best reference available. Pugetbill (talk) 15:08, 29 October 2009 (UTC)

My apologies - either I was using an old link or the BDA has updated their map. The region code map at www.blu-raydisc.com/en/Technical/FAQs/Blu-rayDiscforVideo.html is not (no longer?) as I described above. I will revert the article map to the previous graphic.

In trying to verify the accuracy of the BDA map, I have had no luck finding alternate sources / references. There seems to be very little written about what the correct region code is for some "region-border" countries like Belarus, Ukraine, Papua New Guinea, etc. But since the BDA map is all we have, I will assume it is correct. Pugetbill (talk) 16:34, 29 October 2009 (UTC)

According to BD spec (Region B: - Europe) Belarus and Ukraine are Region B. I think last update on this map which included them to C wasn't correct. --DmitriyR (talk) 14:02, 3 March 2010 (UTC)

How to rip Blu-ray ？

<Comment has been removed>

This is an encyclopedia not a guide to pirating commercial recorded material. Also: the above comment is not a discussion of the article which is what this discussion page ism provided for. 20.133.0.13 (talk) 14:26, 24 November 2009 (UTC)

The problem is advertising not pirating.205.250.255.227 (talk) 20:41, 22 January 2010 (UTC)

I removed the original comment to prevent search engines from picking up the name of the product that had been advertised. Mikus (talk) 17:45, 8 June 2010 (UTC)

Reception

There is nothing about the reception of Blu-ray, either by the public or the industry. I have read an article by an independent film publisher slating the costs of working with the format and I have also read complaints by the public about the performance of the players and their concerns about DRM. —Preceding unsigned comment added by 212.188.161.10 (talk) 13:24, 24 November 2009 (UTC)

See Blu-ray_Disc#End_of_the_format_war_and_future_prospects. Cochonfou (talk) 13:11, 12 January 2010 (UTC)

Technical Specification

The section under the above heading says that Bluray supports up to 25fps progressive at 1920x1080; the cited pdf only specifies up to 24fps and consensus elsewhere is that 24fps progressive is the correct limit. Is there any vaguely official source showing that 1080p25 is supported? http://en.wikipedia.org/w/index.php?title=Blu-ray_Disc&action=historysubmit&diff=327667159&oldid=327354568 is the change, any reason this hasn't been reverted? TNC (talk) 23:28, 27 November 2009 (UTC)

Mandatory vs. optional codec support

I understand how all players have to support a minimum subset of the available codecs and I understand that all discs have to use one of the mandatory codecs for its primary audio tracks. However, the article doesn't explain how a low cost player that lacks support for, say, DTS-HD Master Audio manages to output analogue sound from its stereo audio phono connectors when playing a disc that only purports to have a DTS-HD Master Audio sound track. Is there a backup audio track in one of the mandatory formats that's hidden away and not selectable by the user or advertised on the packaging? MegaPedant (talk) 09:32, 30 November 2009 (UTC)

Cartridges?

Next to footnote 15, the article talks about cartridges no longer being necessary. What cartridges is the article refering to? I'm assuming that in the early days the discs had to be protected from scratches using some sort of cartridge but the article doesn't make that clear.Jimindc (talk) 07:13, 11 December 2009 (UTC)

The original BD spec included cartridges similar to DVD-RAM or to PFD. Cartridges were dropped because they increased the price. Hardcoating is used instead to protect disc surface. Mikus (talk) 17:42, 8 June 2010 (UTC)

Cost of blank discs

Why is Blu-ray media so expensive? —Preceding unsigned comment added by 74.100.52.87 (talk) 18:19, 11 January 2010 (UTC)

Because the technology required to manufacture blank bluray's is expensive and relatively new. CD-Rs, DVD-Rs. DVD-R DLs were expensive too during the first years of their existence —Preceding unsigned comment added by 195.130.121.48 (talk) 18:42, 21 February 2010 (UTC)

Storage Capacity in the Infobox

In the infobox it says for storage capacity:

25 to 50 GB (single layer)
50 to 100 GB (dual layer)
(1 TB to 10 PB) Future 2010 afterwards

My qualms:

• "Future 2010 afterwards" does not seem grammatically correct. Is it trying to say "Late 2010" maybe?
• "1 TB to 10 PB" seems very high to me. I know technology progresses very fast, but 10 petabytes? This year? That is a lot of data. I mean how is 10 PB or 10000 TB supposed to fit on a volume so small? Perhaps it meant 10 TB instead? I not changing because I'm truly iffy on the issue, so I'm looking for clarification to make the edit.

-- Melab±1 ☎ 18:00, 20 January 2010 (UTC)

The limit for DVDs was 2 layers, but with HD-DVD and Blu-Ray companies are experimenting with having several layers. It would be good if there were a citation, but my assumption is that they would reach 10PB using extra layers. It doesn't seem likely that so many layers would be economically viable though. —Preceding unsigned comment added by 96.241.202.243 (talk) 12:38, 18 March 2010 (UTC)

It looks like multi-layer is now more feasible than before. (BDXL announce from BDA via businesswire) http://www.businesswire.com/portal/site/home/permalink/?ndmViewId=news_view&newsId=20100403005024&newsLang=en --205.233.8.190 (talk) 15:01, 5 April 2010 (UTC)

MakeMKV

I was wondering what's about that one. It claims to circumvent any known BD+ and AACS protection. Due my lack of BluRay drives, I am unable to test it, but it's OpenSource [1] and runs on Windows, Linux and Mac. [2] --Mewtu (talk) 03:30, 12 February 2010 (UTC)

Java support

Does this mean that we could see Java games played on Blu-Ray players? —Preceding unsigned comment added by 173.58.251.147 (talk) 05:58, 25 March 2010 (UTC)

Bias for or against + vandalism on article

I've discovered there's a certain bias for or against different companies who worked with this invention (and for that matter, the same is true for the CD & DVD articles here on Wikipedia), particularly Philips and Sony, who where the major contributors to both the CD, DVD and now the Blu-Ray, remain relatively under appreciated in the articles, and thus implying that instead of European and Asian companies, US and other American companies played the main roles in the inventions.

Point 2: There appears to be a great deal of vandalism going on on these articles and topics, this suggesting the need for at least a simi or partial lock on the articles. DaveFlash (talk) 22:16, 26 April 2010 (UTC)

Suggestion: replace "Blu-ray Disc" with "BD" in the article

Why don't we make it very clear at the beginnig of the article what the official acronym is and that henceforth this will be used throughout the article?

Meaning we would replace every instance of "Blu-ray Disc" and "Blu-ray Discs" with "BD" and "BDs" – except where the written out form is necessary (like, when is explained what the acronym stands for, in official product names and such) –, in the same way "CD" / "CDs" and "DVD" / "DVDs" is used instead of the cumbersome "Compact Disc" / "Compact Discs" and "Digital Versatile Disc" / "Digital Versatile Discs", respectively?

That would save A LOT of space, would make the article more readable and do away with or at least clear up some of the confusion with regards to wrong forms such as "Blu-rays" und "BD discs".

What do you all think? – ὁ οἶστρος (talk) 16:42, 5 May 2010 (UTC)

Not acceptable. Not every link goes to the top of the article, thusn anyone linking into a sub section within the article would be forced to guess what 'BD' stands for. 86.182.66.217 (talk) 07:54, 19 May 2010 (UTC)

Well, wouldn't they be "forced" to do that with CD and DVD, too...? I don't get it. (And if this Wikipedia thing somehow isn't about facts – I sorta had the impression it was... – but popular belief, then we should scrap the term "Blu-ray Disc", too, because most people erroneously speak of "Blu-ray Players" and "Blu-rays" in the context of hard- and software, respectively) – ὁ οἶστρος (talk) 16:17, 22 May 2010 (UTC)

Links can take the reader to part way through an article with no clue as to what the whole article is about - especially if that link comes from another article that may have no obvious relationship. For example: Try this link. Although Blu-ray is not abbreviated, 'DVD' is and anyone who didn't know what DVD actually stands for (and a surprising number of people don't) the article provides no clue. The same argument applies to any abbreviation that is scattered through any article. 86.182.66.217 (talk) 16:35, 29 May 2010 (UTC)

This feels like talking to a wall. Did you even READ what I wrote? Four questions, before I give up:

1. Did you ever READ the article Blu-ray Disc? (please, do)
2. Did you ever look at the logo for the format "Blu-ray Disc" / "BD"? (hint: it consists of a "B" and a "D")
3. To be consistent, shouldn't you go here and exchange every instance of "CD" for "Compact Disc" (or rather "Compact", analogous to your insistence on using the wrong form "Blu-ray")?
4. If some people who don't know any better started using the word "cow" for what we (I assume you, too) today call "horse", would you then go here and exchange every instance of "horse" for "cow"?

(by the way, I did reply to the message you left on my talk page) – ὁ οἶστρος (talk) 18:47, 29 May 2010 (UTC)

This is patently absurd. Nobody uses the acronym BD for any reason. CD and DVD are generally accepted abbreviations that everyone understands. Nobody uses BD. Seriously, this is absurd. We want WP to be generally understandable. We don't want to force anyone to read any particular section. But CD and DVD are generally understood, yet BD is simply not. Once again, this whole discussion is absurd. 68.194.226.80 (talk) 04:16, 18 May 2011 (UTC)

"Nobody uses the acronym BD [...]" (68.194.226.80, 2011-05-18)

Not true – simply and patently not so... For Wikipedia to benefit from your contributions, you might want to learn the difference between personal opinions and facts as well as the terms quantity and quality. – ὁ οἶστρος (talk) 15:33, 20 May 2011 (UTC)

Although 'BD' is the official abbreviation of 'blu-ray disc', nobody uses the abreviation in normal everyday speak, unlike 'DVD' or 'CD'. Everyone refers to a 'CD player' or a 'DVD player', but nobody talks about a 'BD player' prefering to call it a 'blu-ray player' (and seldom a 'blu-ray disc player' which would be more technically accurate). DieSwartzPunkt (talk) 11:00, 11 December 2011 (UTC)

That's just not true. Please don't claim things that are not factual but instead pulled out of thin air.

Often, player manufacturers even use the abbreviation in model names.

And you can call me nobody all you want, but there are many other people who use the term "BD", both among everyday consumers and industry professionals (Harris, for example, seems to have stopped using it, though).

It's obvious that they are in the minority, but since when is popular usage a criterion for encyclopædic articles? (again, quantity doesn't equal quality)

"Blu-ray" is informal – slang, if you want –, and there's nothing wrong with that, but that doesn't mean reference texts should employ it. If there's a certain usage threshold reached, a word – whatever its genesis – belongs in a dictionary, but that's it.

And, yes, "Blu-ray 3D" is a correct form, however, "Blu-ray" is not – or not yet: if common misuse persists (covers often read "BLU-RAY + DVD" – right below the "BD" logo –, fora write and commercials speak of "Blu-ray"), at some point in time, the BDA might give in and change the official definitions, but it's not Wikipedia's business to predict the future. – ὁ οἶστρος (talk) 15:43, 11 December 2011 (UTC)

And just this very afternoon, I purchased a portable burner for use with my laptop (Samsumg SE-506). It is described on the box in 1 inch letters as a "Blu-ray writer". The only place 'disc' appears after 'blu-ray' anywhere on the box is in the Blu-ray disc logo. Everywhere else it is either 'BD' or just 'blu-ray'. The minority of people that you refer to, are a majority - at least here. No-one that I know of refers to the format as 'BD' (unless specifically to a BD-R or BD-RW blank disc). Even my brother-in-law (who works for 20th Century Fox marketing - and thus probably talks about them every waking hour of his working life) calls them 'blu-rays'. So I haven't pulled anything out of thin air. Oh yes, and in the 'model name' that you linked to, Panasonic have not used 'BD' in the model name, having spelt out "Full HD 3D Blu-ray Disc Player" in full. DieSwartzPunkt (talk) 17:00, 12 December 2011 (UTC)

Since you obviously couldn't be bothered to properly read what I wrote (assuming you would be able to), I don't think this warrants a response, but, oh well...

• The first few sentences up to "The minority of people..." and the statement regarding your brother-in-law confirm, for example, what I wrote in the last paragraph in brackets.
• I agree, the people using the correct terms are in the minority. That's what I wrote. Reading helps. And yet, minority (even tiny friggin' minority) isn't the same as nobody as you so kindly call me and them (see also the quality vs. quantity argument, which... – gee, enough repetition already...).
• The linked model's name: "Panasonic DMP-BDT210 Full HD 3D Blu-ray Disc Player" (emphasis mine) – also, in the navigation bar above, they [unfortunately] write "Blu-ray & DVD".

You are against using the abbreviation "BD". Understood. I just kindly asked you not to pull things out of thin air (or your behind or wherever you get that stuff from). Regards – ὁ οἶστρος (talk) 21:40, 12 December 2011 (UTC)

Firstly, Don't be so condescending and abusive when replying to others on Wikipedia (doing so is good way to an editing block - See WP:CIV). Wikipedia requires that you treat others with respect and courtesy.

That you believe something to be true does not necessarily make it so. You seem to believe that a model number and a model name are the same thing. In the example that you cited, the model number is DMP-BDT120. No manufacturer spells out 'blu-ray' as part of their model number. The model name is "Full HD 3D Blu-ray Disc Player". Using the model number to bolster a claim that 'BD' is a much used abbreviation in everyday speak comes under the heading of lost causes. DieSwartzPunkt (talk) 12:53, 13 December 2011 (UTC)

You can't be serio..., well, let's make this easier: You win, I lose. [Good heavens! He disintegwated.] Happy holidays – ὁ οἶστρος (talk) 13:53, 13 December 2011 (UTC)

Standard DVDs?

Throughout the article, BD technology is compared to "standard DVD" technology. Why not just refer to DVD as DVD? The current wording carries the implication that a BD is a non-standard DVD. Considering how common the misconception is, the article should clarify the distinction, not reinforce it. A DVD is not a type of CD, and a BD is not a type of DVD, but it's common to hear people talk about Blu-ray DVDs. If the purpose of the phrase is to distinguish between DVD and HD DVD, it's not necessary. If you consider an HD DVD a non-standard DVD, the HD already makes that distinction. Is there any reason that anybody would think that "the ... system used on DVDs..." would be referring to a non standard DVD of some sort? I can't see why "standard DVDs" would be needed in such a phrase. Hagrinas (talk) 00:52, 17 May 2010 (UTC)

Agreed. But then, it looks as if some people here seem to be all FOR reinforcement of misconceptions, if only they are common / widespread enough or even prevalent (see the previous paragraph), and in that "spirit", you probably should stop using the correct acronym for that technology and start calling it "Blu-ray" and "BR" as well... – ὁ οἶστρος (talk) 16:28, 22 May 2010 (UTC)

Actually, although pre-mastered Blu-rays are close to standard DVD technology, they differ in many respects such as encryption and scripting not to mention interactive language. Recordable Blu-ray (both BD-R and BD-RE) are not standard DVD technology as they are really DVD+R and DVD+RW technology. 86.182.66.217 (talk) 16:41, 29 May 2010 (UTC)

Again, it's "Blu-ray Discs" or "BDs", NOT "Blu-rays". Also, please see this. – ὁ οἶστρος (talk) 18:47, 29 May 2010 (UTC)

Blu-ray recordable and blu-ray rewritable discs are sold as "BD-R" and "BD-RE" respectively (says so on every manufacturers' packaging), thus "BD" would seem to be a legitimate abbreviation. Also most people seem to refer to the discs collectively as "blu-rays" avoiding the unnecessary mouthful of "blu-ray disc". 109.157.161.93 (talk) 13:55, 7 December 2011 (UTC)

"Standard DVD" may make some sense when discussed along with 8-cm DVDs ("MiniDVD") or DVD-video-on-CD. "Standard DVD" makes no sense in relation to BD.

On the other hand, there should be made a clear distinction between BD media and BD video standard. It does not help that the video spec is called Blu-ray Disc, or is it called Blu-ray Disc Video? It is a bit clearer with DVD, where media is called DVD, while the video on disc spec is called "DVD-Video". "DVD" by itself does not imply a disc with video programming and should not be used in this context.

I suggest splitting this article into two: one about media and another about video + media package. The article intro says: "Blu-ray Disc is an optical disc storage medium designed to supersede the standard DVD format". So, is this article about storage medium? If yes, then codecs, containers, DRM and other BD-video related stuff does not belong to this article. Mikus (talk) 17:37, 8 June 2010 (UTC)

What is this supposed to mean ?

"In fact, there was no medium with the storage required to accommodate HD codecs, "

makes no sense. The "codec" is the piece of software which encodes and decodes the stored video data. The piece of software is small and it is in the player, not on the disk. Eregli bob (talk) 13:10, 8 June 2010 (UTC)

Title change

I suggest the article be moved to Blu-ray. This article isn't limted to describing the optical media itself, but talks about the whole format specification (codecs, DRM, Java, BD-Live, BD-J, etc), and so it should be renamed accordingly. --uKER (talk) 14:59, 17 September 2010 (UTC)

Sounds good to me. PRRfan (talk) 16:25, 17 September 2010 (UTC)

Not just the medium itself is called Blu-ray Disc, but THE WHOLE FORMAT as well, whereas the term Blu-ray DOESN'T EXIST IN ANY OF THE OFFICIAL DOCUMENTATION; please check for yourself and also see this discussion – ὁ οἶστρος (talk) 00:53, 30 September 2010 (UTC)

No, the correct title (which covers the entire standard; codecs, DRM, Java, etc) is "Blu-ray Disc". —Locke Cole • t • c 17:56, 2 October 2010 (UTC)

Lead section and scope of the article.

About this revert, I had changed the lead to say that Blu-ray is a high definition media format, and it was reverted to say it's a general purpose physical media. As the article stands, it talks about Blu-ray as a video standard, not the discs themselves, so I'd say the lead should be as it was before the revert. Blu-ray discs surely can be used to record whatever you want on them, and it can be made explicit if needed in the appropriate section (Physical Media) but this is not what whole the article is about. --uKER (talk) 04:31, 20 September 2010 (UTC)

Apologies for the late response. I see no reason to deviate from the standard opening set by CD and DVD, especially when the first sentence states that it's designed to supersede the DVD format. And the article does talk about the discs themselves and all its usages i.e. Section 2 - Physical Media. Msgohan (talk) 03:54, 27 September 2010 (UTC)

Well, in fact it was me who created that section in this edit. However, my argument stands. You can record Blu-ray movies (that is, movies compliant with the Blu-ray spec) in discs other than Blu-ray discs, so the article isn't really about Blu-ray discs. --uKER (talk) 13:48, 27 September 2010 (UTC)

Please, uKER, get your facts straight (consult the corresponding white papers). What you write (your perceived distinction in usage of the terms Blu-ray Disc and Blu-ray) is SIMPLY NOT TRUE, and just repeating it time and again won't make it so. See also above and the initial discussion you started about this. I agree with you that the article is not just about the physical disc medium used, but the format as a whole, but BOTH are called Blu-ray Disc (with captial "D"). As for the proper lead sentence, it think yours looked good (and as of this writing, something similar is being used in the article), although I'm not sure the term "medium" couldn't be applied in such a broad sense that it would accommodate the meaning of "format" as well – but I'm happy not to get involved in that discussion. – ὁ οἶστρος (talk) 00:53, 30 September 2010 (UTC)

I've restored the original lead. Not mentioning the data storage usage of Blu-ray Disc in the opening seems like a rather large omission IMHO. While the format is primarily used as a medium for movie distribution, it also has a large usage for data storage (more so with BDXL being available for storage applications). —Locke Cole • t • c 18:04, 2 October 2010 (UTC)

U-Control??

Need some explain for U-Control in article. —Preceding unsigned comment added by 187.66.86.250 (talk) 14:44, 2 October 2010 (UTC)

• U-Control isn't a technology inherent to BD. It's just a branded type of software exclusive to Universal Pictures discs. It just covers a lot of different types of bonus feature-type interactivity for the feature (storyboards, picture in picture, etc). --Sujayt (talk) 15:04, 2 October 2010 (UTC)

Community Screening

I were a bit fast to link to this new article: http://en.wikipedia.org/wiki/Wikipedia_talk:Articles_for_creation/Articles_List_of_Blu-ray_Community_Screening_releases

But I really think it is an important part of the Bluray spec. That differentiate it from DVD very direct, interactive versus non-interactive.

Maybe it should be mentioned here as well: http://en.wikipedia.org/wiki/Blu-ray_Disc#BD-Live

--85.227.250.36 (talk) 11:38, 19 October 2010 (UTC)

Maybe something like this in the BD-Live section: "Community Screening" enables the film distributor to allow its customers an interactive movie experience, often by a live chat with the film director while watching the movie. This is currently only available on some films and require a Bluray player supporting the Bluray 2.0 Profile or greater.

--85.227.250.36 (talk) 11:48, 19 October 2010 (UTC)

If you could establish a foundation for the concept in the article, that would be great. Then it would be fine to proceed with a link to a list. Could you provide references for the proposed text? --Bsherr (talk) 12:27, 19 October 2010 (UTC)

Here is a better BD-Live(http://www.sonypictures.com/homevideo/bluray/bdlive.html) ref. imo, for the community screening part, i thought that the references within the list would be sufficent. --85.227.250.36 (talk) 00:32, 20 October 2010 (UTC)

The references in the list give specific examples, but it would be best to have a reference that explains what community screening is. --Bsherr (talk) 02:06, 20 October 2010 (UTC)

Community Screening allows a viewer(the host) to invite other viewers with the same film to watch it together via the internet. The host become a moderator and is the one controlling functions during the film like paus, fast forwarding or rewinding. The precipitants can also chat with each other. There is also a variant of Community Screening were the film distributor hosts a public event were anyone with a copy of the film can join the director hosting. http://wblive.warnerbros.com/registration/faq.html --85.227.249.2 (talk) 23:14, 5 November 2010 (UTC)

Picture quality: 2D vs. 3D?

The article doesn't mention if there are any differences in picture quality between 2D Blu-ray and 3D Blu-ray. Is the bit rate for one eye in 3D Blu-ray as high as the bit rate in 2D Blu-ray? If it is, how can they manage to put a full length 3D movie in one disc? Urvabara (talk) 19:45, 3 December 2010 (UTC)

This would be better asked on a forum. From personal experience I can say that the quality thus far has been equivalent. For the most part 3D discs are lacking in special features, which frees up space for the 50%+ added bitrate needed for the MVC extension. Additionally, most 2D releases use 40GB or less of the 50GB available. As far as sources that could be added to the article, I can only think of disc reviews which mention comparing the two releases. Msgohan (talk) 19:31, 13 December 2010 (UTC)

Since the left frame and right frame are placed side by side on a regular 1920x1080 field, the actual horizontal resolution of the combined 3D image is halved, so the image for each eye is 960x1080. I have always had a great interest in 3D technology and have a fairly extensive personal museum of 3D material. Having attended a major 3D television demonstration, I felt no desire whatsoever to obtain one. The poor resolution and flickering picture would drive me nuts. 109.157.161.93 (talk) 13:39, 7 December 2011 (UTC)

Blu-ray 3D uses the full resolution and doubles the number of frames. It doesn't store images in side-by-side format. Since you have a great interest in the tech, research and you will find this to be true. Msgohan (talk) 21:28, 7 December 2011 (UTC)

You may be confusing blu-ray 3D with some broadcast 3D (and I wonder if that is what you saw demonstrated). Broadcast TV is forever striving to keep the bandwidth within ridiculously narrow bands largely because their driving factor is maximising the number of channels broadcast not in providing the best picture quality. Blu-ray 3D does indeed store two full resolution (i.e. 1920x1080) frames per frame (if you see what I mean). Thus the data rate read from the disc for 3D material is (slightly greater than) double that for 2D material. This does provide a problem for PC based blu-ray drives connected via a USB2 interface (as most current portable drives are). The 3D data rate is pushing the USB2 interface to its limit and thus it only works (if at all) if the blu-ray drive is directly connected (i.e. not via a hub) and then if no other USB devices are connected (possibly mouse and keyboard excepted). Even then stuttering of the image is not unknown. Whether the picture flickers or not does depend on the actual manner in which the 3D is presented to the viewer. Early sets did have a tendency to flicker, but the best of the current sets seem to have eliminated that problem. DieSwartzPunkt (talk) 17:33, 9 December 2011 (UTC)

Actually, to be stricly accurate, there are three methods by which the 3D content can be stored, and Blu-ray supports all three.

• Side by side as correctly described by 109.157.161.93 above. Usually the province of broadcasters, but Blu-ray 3D players are required to support it. Has half the horizontal resolution of regular HD material.
• Two full resolution frames stored one after the other as described by DieSwartzPunkt above. Obviously full resolution.
• The left frame stored above the right frame similar to the first option but split horizontally instead of vertically. Again Blu-ray 3D players are required to support it. Has half the vertical resolution of regular HD material.

I have not (so far) encountered any 3D discs that use anything other than the second option. 86.169.33.6 (talk) 15:23, 22 May 2012 (UTC)

Region code visual appearance

FYI, on product packaging, the region codes look like this: [3]. Is there a free version of this, or should we scan in some packaging? -- Beland (talk) 21:19, 18 December 2010 (UTC)

If by free you mean libre, scanning in a cover doesn't make it public domain. The source of that image is [this PDF]. The BDA licenses its usage under the same agreement as the BD logo itself, which this article displays with a fair use notice. Msgohan (talk) 12:09, 23 December 2010 (UTC)

Blue-ray not trademarkable?

"The name Blu-ray Disc refers to the blue laser used to read the disc, which allows for six times more storage than on a DVD. The term Blu was used instead of the correct Blue which is commonly used in English (and therefore not registrable as a trademark)."

But common English words are sometimes trademarked. Take Apple and Sandals for instance. Does this mean:

• those two aren't registered trademarks?
• some difference in law between jurisdictions is in play here?
• the law has changed?
• the technology is too close to the literal English meaning of "blue ray" for its developers to be able to claim a trademark on it?

Incidentally, I just read on Compact Disc a mention of the "trademarked Compact Disc Digital Audio logo". That's just as well using common English words with more or less the literal meaning. Do I rightly deduce the point here is that BDA did this in order to trademark the name and not just the logo? -- Smjg (talk) 20:02, 3 January 2011 (UTC)

In most jurisdictions you can trademark a common word (aka something you find in the dictionary) providing the context is not common. "Apple" is one of the most usual examples - you can't trademark it for fruit products because it's common but applied to computers it has no common meaning outside of the products it's TMed for. Bear in mind that trademark law contains a lot of uncertainties and also different companies take different levels of risk. I think "Blue-ray Disc" would have been defensible because it's a compound term that isn't likely to be in much generic use for anything other than this product, but by using a variant spelling the trademark is significantly stronger. Timrollpickering (talk) 03:07, 9 December 2011 (UTC)

For what it is worth, you cannot trademark or copyright a logo. You can only trademark the actual words. If you wish to claim intellectual property rights on a logo, then you need to register it as "a registered device". DieSwartzPunkt (talk) 17:36, 9 December 2011 (UTC)

Huh? Trademark: "A trademark is typically a name, word, phrase, logo, symbol, design, image, or a combination of these elements." Msgohan (talk) 00:39, 10 December 2011 (UTC)

It occurs to me that I am talking about the situation in the UK. Other jurisdictions may vary. DieSwartzPunkt (talk) 10:51, 11 December 2011 (UTC)

3D Specifications Should Be Added

Much of the article applies only to 2D Blu-ray. Blu-ray 3D specifications have been published in section 6 of the specification at http://www.blu-raydisc.com/assets/Downloadablefile/BD-ROM_Audio_Visual_Application_Format_Specifications-18780.pdf. These should be added, or added to a separate 3D-only article. The current article may need to be restructured to make it clear which parts apply only to 2D. It is difficult to integrate the 3D specifications into the existing structure. --NPHope (talk) 16:34, 21 January 2011 (UTC)

Blu-ray (software) players

The article should at least link to a list of software players. Or is there a reason there is not a single mention of the (un)availability of software players on various platforms? bng 90.179.239.97 (talk) 16:27, 27 January 2011 (UTC)

Poorly Written Article; Ambiguous in many areas

Can someone who is technical and knowledgeable about BRD's please read the material and edit it for the many ambiguities and possibly mis-stated information? Here is an example: "Blu-ray recorders are not being sold in the U.S. due to fears of piracy. Personal computers with Blu-ray recorders are commonplace." Which is it? Also, the order of the presentation of material is so confusing and illogical that it is very difficult to follow. Wikipedia does not need to have this kind of poorly written article displayed. If you are interested in keeping this article, please clean it up 71.41.155.82 (talk) 18:03, 28 February 2011 (UTC)jonathan ayres

Instead of complaining, why not have a go yourself? 86.182.71.209 (talk) 16:33, 5 March 2011 (UTC)

Fully agree. The article is a mess. The text in the introduction to the History section is NOT a history of Blu-Ray technology, is is a fuzzy & unscientific tale about 'blue lasers', with no reference at all to Blu-Ray. If this article is ever to get serious, this text must be completely replaced by a knowledgeable account. --AVM (talk) 13:48, 4 May 2011 (UTC)

Agree. I removed the detail pertaining to blue laser diodes - it's covered elsewhere, e.g. blue laser. Kbk (talk) 00:13, 26 May 2011 (UTC)

Compression

I was looking for the compression ratio for Blu-ray codec; if it is in this article, it is not easy to find. This would be a useful thing to add. Geoffrey.landis (talk) 18:51, 8 March 2011 (UTC)

Blu-ray photo in the infobox

I think the Blu-ray Disc photo in the infobox is a bit misleading... Most of the Blu-rays for sale today are a silver color that is very similar to a DVD or CD. The disc in the photo is probably either a BD-R or a BD-RE. The reason I think the photo is misleading is because somebody might go to Wikipedia to see what a Blu-ray disc looks like, and they'll get the impression that it's purple/blue, especially with the name of the standard being "Blu[e]-ray". — Alex Khristov 17:53, 12 March 2011 (UTC)

It's a pressed single-layered movie disc; note the "BVSS" serial number. Part of the reason for the milkiness is likely light shining through the top label. You're welcome to improve the article by scanning a silver disc yourself, of course. Msgohan (talk) 20:54, 14 March 2011 (UTC)

status of term Blu-ray

In the first line (in parantheses) of this version, it reads

"[...] and official shortened name is Blu-ray"

I'd appreciate it if someone showed me an official source (something like a white paper by the BDA will do) for this, as don't think that's true. Blu-ray 3D is an official term, Blu-ray, as far as I'm aware, is NOT. If evidence can not be established, this should be changed back – ὁ οἶστρος (talk) 20:40, 10 April 2011 (UTC)

Yes, it is the official shortnened name. http://www.blu-ray.com/faq/#bluray_name

Kokken Tor 12:40, 11 April 2011 (UTC) — Preceding unsigned comment added by Kokken Tor (talk • contribs)

The site you mention is a great place for information about the different BD editions of a film out there and a nifty collection management tool, but you do realize it has nothing to do with the BDA, do you? Actually, most likely they chose the domain name Blu-ray.com because it isn't official and therefore was obtainable (by the way, the same site – as of 2011-04-11 – at the top of its homepage carries as its introduction the following: "Welcome to Blu-ray.com, your source for everything related to Blu-ray Disc (BD), sometimes incorrectly referred to as Blue ray, Bluray or Blu-ray DVD"). So, I'm still waiting for any validation of the above claim. – ὁ οἶστρος (talk) 14:12, 11 April 2011 (UTC)

This is taken from the official site of BDA. http://www.blu-raydisc.com/Assets/Downloadablefile/general_bluraydiscformat-15263.pdf

Under their trademark it says Blu-ray.19:00, 11 April 2011 (UTC)Kokken Tor — Preceding unsigned comment added by Kokken Tor (talk • contribs)

You are right, it is a trademark now and a term used several times throughout the paper you refer to, although I'd be curious about the history behind that, as I don't recall having seen it (not that that means much, but still) in any tech specs when the format was introduced (for example, it doesn't show up once here), and the fact that an independent company was able to secure the Blu-ray.com domain name also appears rather curious to me; maybe they just relented to incorrect popular usage? But then, by the look of it, in that document, Blu-ray doesn't seem to be used interchangeably and in the same sense as Blu-ray Disc: they now seem to be making (or have been making from the start?) a distinction between the format itself (Blu-ray Disc / BD) and the blue laser beam technology it is based upon (Blu-ray) – "seem" because I'm not in a position to really judge this, maybe someone else can clarify. If true, however, then referring to the format as Blu-ray and the movies as Blu-rays would still be wrong. Further, this then obviously might have implications for the way the article is to be worded and structured – maybe a separate article altogether should be created. What do you think? – ὁ οἶστρος (talk) 03:28, 12 April 2011 (UTC)

I don`t know but, i believe it`s the right shortened name. I say it should stay there. — Preceding unsigned comment added by Kokken Tor (talk • contribs) 13:58, 12 April 2011 (UTC)

OK, duly noted. I'm on the opposite side of the argument, I think the wording should be reverted back to the way it was up until last month. Would anybody else like to chime in, maybe the people who started and made the first few edits to the article? – ὁ οἶστρος (talk) 20:20, 12 April 2011 (UTC)

Video resolution chart

The chart found in http://en.wikipedia.org/wiki/Blu-ray_Disc#Video does not contain any 1920x1280 resolutions over 30fps, so it's easy to think that BD does not support 1080/50i or 60i. — Preceding unsigned comment added by 194.132.95.241 (talk) 10:29, 1 August 2011 (UTC)

This is explained in the very first note to the table ([a]) which explains that the the rates are interlaced and denoted as frame rates rather than field rates. Msgohan (talk) 22:17, 1 August 2011 (UTC)

Capacity verses Layers

The article states each layer contains 25GB. Yet the triple layer disk contains 100GB and quadruple layer 128GB. The article should explain this anomaly. -58.108.188.6 (talk) 06:21, 1 September 2011 (UTC)

Wavelength and Storage space

The article says - While a DVD uses a 650-nanometer red laser, Blu-ray Disc uses a 405 nm blue laser . This shorter wavelength allows for over five times more data storage per layer than allowed by a DVD. It is not described why and how this shorter wavelength allows for more data stoarage. It will be helpful if this technical information is provided. Thanks.
Anish Viswa 08:46, 1 September 2011 (UTC)

Storage capacity is proportional to the square of the laser's focussed spot size (itself proportional to the wavelength of the light). Remember that not only can you get more data along any track, you can also space the adjacent tracks closer together. 109.153.242.10 (talk) 17:53, 18 December 2011 (UTC)

Blu-Ray

Hi, i believe that the blue ray is not actually a blue laser but it;s a violet beam am i right? — Preceding unsigned comment added by Commando112p (talk • contribs) 12:28, 17 October 2011 (UTC)

Clearly stated in the article: http://en.wikipedia.org/wiki/Blu-ray_Disc#Laser_and_optics Msgohan (talk) 00:25, 18 October 2011 (UTC)

Number of available titles

The number of available titles in the lead section uses the Now Available page of blu-ray.com as its source. However, the number of titles does not seem to be available directly on that page, which is a big list. By checking the number of pages of the list, we can have an assessment on the number of titles listed: I find 6300+ in the US, and 3700+ in the UK, which is quite different from what is currently written in the article. Am I missing something, or is this information outdated ? Thanks for your help. Cochonfou (talk) 08:01, 31 October 2011 (UTC)

Using a blank search with my site preferences set to US only and unchecked "show all Region Free titles", I get 7552 US titles. But this counts things like "Africa 3-pack Blu-ray" separately from its constituent releases, collector's editions separate from regular, etc. I don't know how you would filter those out. Msgohan (talk) 07:43, 1 November 2011 (UTC)