Talk:High-Definition Multimedia Interface

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Contents 1 DRM 2 Extent of Backwards Compatibility 3 Next-Generation consoles 4 Clarification 5 Is HDMI Type B equivalent to double cabled DVI 6 Licensing 7 Improvement over other Interfaces 8 Compatibility 9 Merge with Unified Display Interface 10 First version 11 HDCP 12 More HDCP 13 TIME CODE 14 Cable Costs 15 HDMI versus Component 16 Picture request 17 Manier? 18 Confusion? 19 New table problems 20 hdmi versions 21 Common connecting examples... 22 Vista? 23 Unclear how DVI signal is helped by using HDMI cables 24 1440P Confusion 25 Cable costs - explanation? 26 HDMI Flashing Picture Problem

[edit] DRM

Is it related with the DRM/encryption? I keep hearing about it...

Yes. HDMI supports HDCP, which is a form of DRM. HTH. --Heron 20:36, 30 January 2006 (UTC)

Yes. It's called HDMI-CP, and will be required to view HD-DVD/Blu-ray movies in Windows Vista.

Wulf 02:49, 22 March 2006 (UTC)

This should be (and now, 1 Sept 2007, is) clearly stated. The wording has a lot of pro-DRM indirect propaganda. —Preceding unsigned comment added by 81.38.118.205 (talk) 05:12, 1 September 2007 (UTC)

[edit] Extent of Backwards Compatibility

Since DVI connections can support analog and digital signals, it has been unclear to me whether or not one could use a VGA-DVI adapter and a DVI-HDMI adapter in serial in order to connect a VGA source with an HDMI receiver. It now seems to me that this would not work at all, given that HDMI is apparently digital-only. I think that this article would be a good place to put a clarification of this for people like me. I don't want to do the editing myself, though, because I don't really know anything for sure. --Jmacaulay 15:15, 15 March 2006 (UTC)

---

ANSWER: HDMI is digital only, so no, a VGA source cannot be connected to a digital display via HDMI. As for a DVI source, as there are 2 types of DVI connectors - digital only (DVI-D) and digital+analog (DVI-I), either will drive an HDMI display using a DVI-to-HDMI cable if the source is digital. For further reference, try http://www.hardwarebook.net/connector/av/dvi.html

[edit] Next-Generation consoles

The PS3 will have 1 HDMI connections, I hope the Microsoft will add it soon to their console. (201.145.144.97 22:14, 20 April 2006 (UTC)).

The port on the back of the Xbox 360 is proprietary, so it is conceivible that it can connect to a wire with a HDMI output. However, HDMI is NOT neccissary for any video game, under the realization that you can't just watch a video game like you can watch a movie, and that leting people use a fully HD signal with componet cables or a moniter's cable would actually boost publicity, and thus profits, by advertising for your games. One great example of this is Red vs. Blue. - 68.228.33.74 04:51, 9 October 2006 (UTC)

I dont know about the xbox, but PS3 will support HDMIver1.3 (both consoles)--sin-man 03:00, 30 October 2006 (UTC)

[edit] Clarification

It is independent of the various DTV standards such as ATSC, DVB(-T,-S,-C), as these are encapsulations of the MPEG data streams, which are passed off to a decoder, and output as uncompressed video data, which can be high-definition.

Is this how the other standards work or hdmi?

Reference of Image Constraint Token lacks, but,I may have gone over the article too quickly [1]

[edit] Is HDMI Type B equivalent to double cabled DVI

Could someone please provide a photo of the new HDMI Type B connector? HDMI Type A is equivalent to DVI Dual Link; Is HDMI Type B equivalent to the double cabled connections used for large digital monitors i.e. Apple and Dell's 30" widescreen models? Will we see latched HDMI (part of UDI (Unified Display Initiative))) replace DVI on computers?

• According to the article, Type A HDMI is compatible with single link DVI-D and Type B HDMI is compatible with dual link DVI-D. If this isn't true, the article needs to be fixed. Herorev 07:59, 9 August 2006 (UTC)

[edit] Licensing

I think there should be some discussion of licensing, and how that has triggered the DisplayPort and UDI efforts. --Belltower

That would be a fairly complex issue and some of it is less than clear cut. For instance DisplayPort is currently license/royalty free but at any time the companies that made it could exert there patents on it. Furthermore HDMI licensing is $10,000 yearly with only a 4 cents royalty per HDMI device (regardless of the number of HDMI connections) so except for the smallest of companies it is not even an issue. Also as of May 2008 the UDI website has been down for several months and looks to have been dead for at least the last year. UDI was basically just a stripped down version of HDMI 1.3 that tried to remove some of the features to reduce the licensing costs. When several of the computer companies though decided they wanted it completely license/royalty free and joined up with DisplayPort I think all development on it died. Personally I don't see any problem with that since HDMI 1.3 is perfectly capable of being a computer interface. Whether it will end up being widely used as one though is another matter. --GrandDrake (talk) 16:30, 6 May 2008 (UTC)

[edit] Improvement over other Interfaces

I need a technical explanation for why any other interface (specifically HDMI) on the DTE side of a cable box would be better than the standard coax connection. The cable feed arrives through a coax connection, so how can a different interface from the cable box to the HDTV provide a better quality picture and sound?

ANSWER: The cable box is tuning digital cable not analog this is the key to why these interfaces are better than standard coax. With new display technologies such as DLP, LCD, LCoS, and plasma able to recieve digital signals and DVI and HDMI able to transmit uncompressed digital signals the TV is receiving the most error free signal possible. If you were to use the RF output or even sVideo or baseband outputs of a cable box the box must first receive and decode the digital signal, than do a digital to analog conversion and remodulate the signal for use on an analog input on a television. As you can guess you lose information in doing that, not to mention these outputs are not capable of high definition. Even though the YPbPr outputs are capable of 1080i output there is a D-to-A conversion that has inherent signal degradation. With HDMI able to transmit multi-channel digital audio as well as HD video, not to mention the use of EDID handshaking, I think I would use it over remod coax. —The preceding unsigned comment was added by 129.188.33.222 (talk • contribs) .

Even a cable box which takes in video content in analog form (the cheaper subscription to cable TV!) will benefit the user in the picture on the screen. The analog signal is converted one time, in the set-top box, and then sent to the TV in digital form over HDMI (as the previous append explains). The analog-to-digital conversion in the set-top box is quite good, in most cases, even though the incoming analog content is limited to SDTV, and not HDTV.Calbookaddict 05:38, 30 March 2007 (UTC)

This is true, however it needs to be said that SD content on an HD TV looks terrible. This is because the TV or STB is forced to interpolate (intelligently make up) pixels that dont exist in the video signal. In reality analog sevices look the best on 480i analog TV's. I have seen too many people spend 2000 dollars on a TV and refuse to get HD cable service, this is an enormous waste of money. —Preceding unsigned comment added by 129.188.69.145 (talk) 15:32, 14 December 2007 (UTC)

With regard to "SD content on an HDTV looks terrible"... "Everything looks better on an HDTV. Even non-HD broadcast TV looks better, thanks to a technial marvel called "upscaling," plus several other technical innovations. -Bill Machrone (columnist/contributing editor PC Magazine), writing in The Wall Street Journal, Jan 7, 2008, page s1. -Dawn McGatney, Jan 7, 2008. —Preceding unsigned comment added by McGatney (talk • contribs) 23:02, 7 January 2008 (UTC)

[edit] Compatibility

Will an HDMI 1.3 cable work to its fullest using an HDMI 1.2 female connector?

[edit] Merge with Unified Display Interface

Why? --Heron 17:10, 1 August 2006 (UTC)

[edit] First version

Was 1.1 the first version, or was there a 1.0? -- Mattbrundage 19:35, 5 September 2006 (UTC)

Added 1.0 specs -- Mattbrundage 15:19, 21 November 2006 (UTC)

[edit] HDCP

Any knowledgeable person knows that HDMI is just a part of the CARROT (High Definition) that the ones in the business (Hollywood, MPAA, "content providers" and others) are putting in front of the ASS (the consumer), to lure it to the PATH (enforcing draconian DRMs and limiting the consumers' freedom) they want.

The other parts would be, of course, Blu-ray, HD-DVD or whatever other stupid format with a bazillion times more storage capacity, while the bitrate of the content (movie) is also raised to a bazillion times more (to keep one movie per disk), and all the HD paraphernalia (TVs, BD players...). And, of course, they'll come with DRMs built-in.

To me, HDCP should be much more predominantly mentioned in the article. The whole point of the HD "revolution" is to enforce DRMs (and sell in Blu-ray format movies that where already sold in DVD, and before that in VHS). At least the VHS->DVD step WAS revolutionary. Blu-ray and their kind ONLY offer higher resolution, at the price of unacceptable DRMs. This should be made prominent! Isilanes 20:12, 6 September 2006 (UTC)

It is useful to point out that, as of the HDMI 1.3a Specification, with its Compliance Test Spec, there is a requirement that any HDMI system which implements HDCP must do so in a way fully-compliant with the HDCP Specification. Earlier versions of the HDMI Spec did not explicitly require that HDCP implementations be tested to be fully compliant, in order to attain compliance to the HDMI Spec itself. This enhancement in HDMI 1.3a will greatly improve interoperability among HDMI systems (those tested to HDMI 1.3a), so that the end user's experience improves. Ideally, the end user should never see HDCP turning on or off, nor any visual or aural effects of HDCP.Calbookaddict 05:44, 30 March 2007 (UTC)

It should also be noted that there are no commercially available Compliance Test Equipment devices. There is one company, Simplay Labs LLC (a subsidiary of Silicon Images, who holds the market for HDMI chips) that offers HDCP compliance testing based upon their own SimplayHD Compliance Test specification (EETimes article, Consumer testing hijacked?). The SimplayHD Compliance Test Specification is not available for free or for purchase. The downside that I see is that without having the SimplayHD CTS, there is no assurance that it is compliant to the HDCP Compliance Test Specification. --IlliniFlag 17:17, 9 November 2007 (UTC)

Note that the HDCP Compliance Test Specification used by the authorized test centers worldwide is available on the web at http://www.digital-cp.com/specs/HDCPSpecificationComplianceTestSpecification1_1.pdf. Intel wrote the original HDCP Spec, and continues to maintain it. They have provided this compliance test spec in recent months. It is true, as stated earlier, that test equipment to perform the tests in the CTS is not available. But the definitions of the test in the referenced PDF file (133 pages) go a long way to showing how compliance is checked.Calbookaddict 02:41, 10 November 2007 (UTC)

High-bandwidth Digital Content Protection) An encryption system for enforcing digital rights management (DRM) over DVI and HDMI interfaces. The copy protection system (DRM) resides in the computer, DVD player or set-top box. If it determines the video material must be protected, it encrypts the signal via HDCP and transmits it to the display system, which decrypts it. HDCP enforces copyrights of content that flows through HDMI/DVI connections. HDCP is essentially a way to get the device makers follow the wishes of content providers. Device makers must get licenses that will equip their devices with licensed keys. These keys will enable them to receive and display encrypted content. To get the license, they agree to honor flags in the content that will generally limit the storage and re-transmission of content. HDCP was originally developed by Intel Corporation. It is now published and maintained by Digital Content Protection. There is an incompatibility between HDCP enforcing transmitters and receivers that are not HDCP enabled. Now as the standard evolves, each generation will continue to see the same compatibility problem —Preceding unsigned comment added by 202.162.160.31 (talk) 19:22, 3 October 2007 (UTC)

[edit] More HDCP

It's also worth noting that HDMI doesn't require that content be encrypted. The content provider (Blu-Ray disc, cable company, etc.) has to set a flag to instruct the source to encrypt content. For instance, plain old DVDs do not need to be copy protected. I've come across several HDMI-enabled up-converting DVD players that don't support/require HDCP. Then again, there are other players out there that just take the "safe" route and HDCP-protect everything.

[edit] TIME CODE

Unlike HD-SDI, HDMI does not provide time coding within the protocol. One could time the transfer of video data by counting frames (of course, also knowing the frame rate). the InfoFrame Packet structures specified in HDMI do include a generic InfoFrame, which could be loaded with time-stamp data, but this would be a vendor-specific solution and not compatible among different, disassociated vendors. Calbookaddict 00:04, 23 March 2007 (UTC)

—Preceding unsigned comment added by 202.162.160.31 (talk) 19:15, 3 October 2007 (UTC)

[edit] Cable Costs

I keep hearing from technically inclined friends that since HDMI uses a digital signal, your TV will either work perfectly or not at all. They say that a $5 cable will work as well as the argon-filled, platinum plated, precision balanced, fairy dust sprinkled $80 ones. Maybe some one should comment on that in the article. —The preceding unsigned comment was added by 209.217.75.174 (talk) 20:49, 22 January 2007 (UTC).

Since the article is not a buyers guide, it seems inappropriate to make a generic claim, even though it might be helpful to people considering buying equipment. Its worth nothing the article does already mention that any cable which can meet the transmission specs is appropriate (it just doesn't explicitly say "regardless of the cost"). - Davandron | Talk 22:34, 25 January 2007 (UTC)

I added a couple of sentences to the criticisms section addressing the cost issue. The difference in cable prices is extreme enough that it's made it to some major blogs. If you google for "hdmi cables", 3 of the top 10 links talk about the cost issue. Searching for "hdmi cable scam" gives 300K results. I think it belongs in the article. Being helpful to buyers is just a little bonus.68.8.110.219 06:38, 16 March 2007 (UTC)

[edit] HDMI versus Component

I think it would be helpful if their could be a section that compares HDMI to Component. I think this is something that people, including myself, often wonder about. While I realize HDMI is digital while component is analog, it's not clear what kind of difference this makes to image quality. Attila226

I came here to ask the same question. -Indolences 16:01, 1 May 2007 (UTC)

Think abou it. You picture is in digital format on your DVD or Blu-Ray disk, it's then got to be converted to analog component parts to be sent up a component cable, assuming you have a digital panel, you then need to recompile the picture and resample it back into a digital picture to display on your digital panel.. Lots of conversion and messing around with signals.. For HDMI, it's a pure digital signal path.. —The preceding unsigned comment was added by Mgillespie (talk • contribs) 09:47, 14 May 2007 (UTC).

I have verified with Sony that at least on their Bravia LCD HDTVs, Closed Captioning cannot be interpreted by their HDTV if the signal is supplied through an HDMI input. Their Knowledge Articles referencing this lack are C352674 and C83284. Unless the set-top box or the DVD player interprets Closed Captioning themselves and passes it on in the video output, the HDTV will not perform this function with HDMI as input. The suggestion if the set-top box or the DVD cannot do this, one must use a Component, S-Video, or Composite connection. I have seen little discussion of this problem elsewhere in HDMI discussions, and since Closed Captioning can be very important to the hearing-impaired, I'm passing what I've learned along. Perhaps someone else can comment further on this or discuss when and if an HDMI Closed Caption Standard and implementation will be forthcoming. This may be one reason to choose a Component connection instead of HDMI presently. Jwdening (talk) 22:17, 24 February 2008 (UTC)

[edit] Picture request

Can you add a close-up picture of the end connector to the article along with something to compare its size to like a USB or (a context appropriate) DVI end connector or even just a ruler? Even better would be the inclusion of a picture of a HDMI female port. Just saying because based on the pictures included in the article right now I would be hard pressed to recognize it instantly in the wild if I were to come across it in a context free situation. --70.51.229.95 23:08, 18 May 2007 (UTC)

Sorry about the lack of focus - a limitation on my camera - but here's a picture with a ruler. The HDMI plug is on the left, the USB plug is on the right.Calbookaddict 01:12, 19 May 2007 (UTC)

HDMI plug (left) compared to USB plug (right)

Even out of focus, the image looks right as a thumbnail. I've added it to the article. That was really quick response! Great job! --70.51.229.95 01:51, 19 May 2007 (UTC)

What units is the ruler measuring in? Looks too big to be cm, must be some archaic unit :-) TiffaF 06:17, 21 May 2007 (UTC)

The units are inches. I would have thought that the finer divisions of length, being into eighths and sixteenths, would be a dead giveaway that it's not centimeters and millimeters. Sorry, American-centric habit, I suppose. Can someone explain to me why IC packages have dimensions in metric units, while PCB dimensions are in English units? Go figure.Calbookaddict 05:47, 22 May 2007 (UTC)

Note that there is also a Type C connector (and plug) defined in the HDMI 1.3 Specification. It's smaller than the Type A shown in the picture. I don't have one here at home, but they're available already.Calbookaddict 05:52, 22 May 2007 (UTC)

FYI, the original 1970's Texas Instruments 7400 series chips had 0.1 inch pin spacing, and it stuck as a standard, though it is now quoted as "2.54 mm". Newer smaller chip designs are in metric.

BTW, I looked up this article because I noticed all the flat screen TVs and DVD players in my local shops suddenly now have HDMI connections, and at least one DVD player did not have a Scart output. Looks like analogue Scart is being phased out in favour of digital HDMI. TiffaF 07:05, 22 May 2007 (UTC)

[edit] Manier?

Just for clarification, in the criticism section is "manier" supposed to be "more"? This is not an English word, and I can find no reference to this through an online search (except that it appears to be a word in other languages).

He's just trying to say "more many", since "many" is obviously an adjective (note the -y ending). Points for trying, I guess. "plugfest events (i.e. manufacturer conferences)" seems like a false appositive.

[edit] Confusion?

I have an HDMI labelled Toshiba progressive-scan DVD (and a bajillion other formats) player. I do NOT have any HDMI capable receivers or television. The DVD player has HDMI, component (RGB), S-Video, and A/V (yellow) video outputs, as well as RCA, Digital and Optical audio outputs. The RCA and Optical audio outputs work normally, but I can't seem to get a signal out of the video to save my life. Am I out of luck without an HD tv or receiver? --Snicker^|¥°^€| 03:01, 4 July 2007 (UTC)

This question is not related to the article itself. Ask the question in an A/V forum (such as this. -- Mattbrundage 17:56, 6 August 2007 (UTC)

[edit] New table problems

The max color depth information is inaccurate, it is true that RGB is limited on earlier versions to 24 bits but AFAIK all versions of HDMI can do 30 and 36 bit 4:2:2 component. --Ray andrew 04:43, 31 July 2007 (UTC)

This is consistent with what I have read, and also some of the text elsewhere in the post: "Pixel encodings: RGB 4:4:4, YCbCr 4:4:4 (8-16 bits per component); YCbCr 4:2:2 (12 bits per component) " but someone changed my table.

The General Notes state that "8-channel uncompressed digital audio at 192 kHz sample rate with 24 bits/sample". I interpret this as 8 ch, 192kHz, 24 bits is available at the same time. Is this true? In that case, the table could be simplified.

The table originally was supposed to display why and when anyone would need HDMI 1.3 with all exceptions, but now that clarity is lost.

You are correct about the audio, 8 ch of 192kHz @ 24bit is available with any video mode. I agree that the table has been made to complicated, and I would suggest if there is no objections that we trim it to just the major revisions (1.0,1.1,1.2,1.3) --Ray andrew 18:48, 31 July 2007 (UTC)

________________________________________________________________________________________

New problem...

I have a HD ready tv, a dvd player that can support high definition. If i connected each other by a hdmi cable does that mean i can watch dvds in high definition if i put a high defintion dvd in. Plus if i can is it true i can only play hd movies on blu ray? Finally if i cannot do i have to by a dish for it?

Thanks

_____________________________________________________________________________________________ —Preceding unsigned comment added by 79.73.214.192 (talk) 16:51, 17 February 2008 (UTC)

[edit] hdmi versions

the hdmi versions on the article doesnt make any sense to me. Hope this helps....

Specifications, Versions, and Capabilities

HDMI version 1.0 met the goals of the HDMI Working Group and provided a true one-cable solution for uncompressed HD video and multi-channel audio including Dolby Digital and DTS bit streams (more on format support later).

Version 1.0

HDMI v1.0 was the original format, released in December 2002. It took DVI's video signal format and added in the ability to carry a Dolby Digital or DTS bitstream or only two channels of PCM audio (48kHz, 24-bit). The two-channel PCM restriction worked fine for connections between cable/satellite receivers or DVD players and a stand-alone HDTV (which only supported two channels of audio) but it wouldn't be able to support the new audio formats that were slated to accompany HD optical discs (HD-DVD and Blu-ray). Adoption of HDMI v1.0 was sluggish, as DVI-HDCP had a headstart in the market. It didn't help that HDMI shares DVI's cable length restriction – anything more than about 15 meters violates the specification and is likely to require either a booster or a conversion to fiber optic.

2. Version 1.1

It was with Version 1.1 (released in May 2004) that HDMI was finally able to make a compelling argument for superceding DVI-HDCP. HDMI could now carry multichannel PCM audio (eight channels at 192kHz, 24-bit) in addition to Dolby Digital and DTS compressed bitstreams. Version 1.1 also added support for passing the bitstream data from DVD-Audio discs, which previously had to be decoded inside the player and output as six channels of analog or passed as a bitstream through IEEE-1394 (also called FireWire or iLink, a connection type that never saw widespread adoption). HDMI 1.1 was a relatively minor update. The primary feature was to add some packets of audio-related content protection information. These packets were required by DVD-Audio in order to permit DVD-Audio content transmission on HDMI. HDMI 1.0 had the audio and video bandwidth and capabilities and HDCP already had the content protection capabilities, but there was some data that the DVD-Audio folks wanted to send to HDMI/HDCP sinks to tell them not to send the DVD-Audio content elsewhere.

    3. Version 1.2

HDMI v1.2 was adopted in August 2005 (v1.2a was adopted in December 2005 and added some testing and certification language). The only notable difference between it and v1.1 is support for a DSD (one bit audio) digital bitstream. This means that a player can now send the raw digital signal from an SACD over HDMI to a receiver or processor, eliminating the need for decoding of the DSD signal at the player. As for HDMI 1.2, several companies have requested enhancements to the HDMI spec that are being considered by the HDMI Founders, but these items are, by agreement, not permitted to be discussed publicly until the specification is released. The HDMI Founders designed the HDMI specification to be dynamic. As such, HDMI has plenty of extra bandwidth to accommodate future audio and video requirements, and the Founders are committed to evaluating and updating the specification to accommodate new audio and video formats that may be introduced in the foreseeable future.

The HDMI 1.2 specifications are: • Support for One Bit Audio format, such as SuperAudio CD's DSD (Direct Stream Digital) • Changes to offer better support for current and future PCs with HDMI outputs, including: • Availability of the widely-used HDMI Type A connector for PC sources and displays with full support for PC video formats • Ability for PC sources to use their native RGB color-space while retaining the option to support the YCbCr CE color-space • Requirement for HDMI 1.2 and later displays to support future low-voltage (i.e., AC-coupled) sources, such as those based on PCI Express I/O technology

    4. Version 1.3

The HDMI 1.3 specification more than doubles HDMI’s bandwidth and adds support for Deep Color technology, a broader color space, new digital audio formats, automatic audio/video synching capability (“lip sync”), and an optional smaller connector for use with personal photo and video devices. The update reflects the determination of the HDMI founders to ensure HDMI continues evolving ahead of future consumer demands. New HDMI 1.3 capabilities include: • Higher speed: HDMI 1.3 increases its single-link bandwidth from 165MHz (4.95 gigabits per second) found on Version 1.1 to 340 MHz (10.2 Gbps) to support the demands of future high definition display devices, such as higher resolutions, Deep Color and high frame rates. In addition, built into the HDMI 1.3 specification is the technical foundation that will let future versions of HDMI reach significantly higher speeds. • Deep color: HDMI 1.3 supports 30-bit, 36-bit and 48-bit (RGB or YCbCr) color depths, up from the 24-bit depths in previous versions of the HDMI specification. o Lets HDTVs and other displays go from millions of colors to billions of colors o Eliminates on-screen color banding, for smooth tonal transitions and subtle gradations between colors o Enables increased contrast ratio o Can represent many times more shades of gray between black and white. At 30-bit pixel depth, four times more shades of gray would be the minimum, and the typical improvement would be eight times or more • Broader color space: HDMI 1.3 removes virtually all limits on color selection. o Next-generation “xvYCC” color space supports 1.8 times as many colors as existing HDTV signals o Lets HDTVs display colors more accurately o Enables displays with more natural and vivid colors • New mini connector: With small portable devices such as HD camcorders and still cameras demanding seamless connectivity to HDTVs, HDMI 1.3 offers a new, smaller form factor connector option. • Lip Sync: Because consumer electronics devices are using increasingly complex digital signal processing to enhance the clarity and detail of the content, synchronization of video and audio in user devices has become a greater challenge and could potentially require complex end-user adjustments. HDMI 1.3 incorporates an automatic audio/video synching capability that allows devices to perform this synchronization automatically with accuracy. • New lossless audio formats: In addition to HDMI’s current ability to support high-bandwidth uncompressed digital audio and currently-available compressed formats (such as Dolby® Digital and DTS), HDMI 1.3 adds additional support for new, lossless compressed digital audio formats Dolby® TrueHD and DTS-HD Master Audio™. Its bandwidth will be upgraded from 165MHz to 225MHz (but can go up to 450MHz if necessary). The increased bandwidth enables displays to handle 1080i at 60Hz with 36-bit RGB color or 1080p with 90Hz refresh rate with 36-bit color. The new HDMI 1.3 will also support Dolby HD and DTS-HD audio standards (v1.2 only supports Dolby Digital 5.1 and DTS standards). —Preceding unsigned comment added by 202.162.160.31 (talk) 19:30, 3 October 2007 (UTC)

I would mention that two of the statements in that post are wrong. The statement that HDMI version 1.0 was limited to "only two channels of PCM audio" is a common misconception and HDMI has always been capable of up to 8 channels of PCM audio at 24-bits/192-kHz. The statement that HDMI cables over "15 meters violates the specification" is also wrong since there is no fixed limit for HDMI cables. --GrandDrake (talk) 16:46, 6 May 2008 (UTC)

[edit] Common connecting examples...

I would like to know when I need this kind of connection and what connects to what... now that I know what HDMI is...

Example... I have a Comcast digital cable box with a HDMI connector on it. I have a LCD TV that has a HDMI connector on it. Both devices also have coax connections. The signal arrives via the coax to the cable box. So, do I need the HDMI to get the best picture or is the coax connection from the cable box to the TV as equal to/better than/worst than the HDMI connection? If equal to or better than HDMI, then why is there a HDMI connection on the cable box in the first place?

Would the cable box HDMI be used to connect to the DVD-R to record movies in HD?

(long winded - sorry) So HDMI is used to connect: DVD/bluray player to TV only? cable box to anything?? DVD camera to TV?? —Preceding unsigned comment added by 209.98.246.21 (talk) 19:15, 15 October 2007 (UTC)

Your coax cable is carrying the "cable" content, either analog or digital, to the set-top box. I'm not sure about the purpose of the output coax cable from the cable box. But the HDMI output allows direct connection to the TV, to an A/V Receiver, to an HDMI switch, etc. A single HDMI cable carries the video and the audio, as well as control information.Calbookaddict 15:56, 7 November 2007 (UTC)

[edit] Vista?

It is mentioned in the article "a PC running Windows Vista". As I understand it, that is not really true. Since I am a Linux user myself, and interested in buying a laptop, I googled to find if this is true. A mailing list claims that, for example, a Linux box could also use HDMI. It is probably confused with HDCP, that runs over HDMI/DVI, which is 'supposed' to provide an encrypted link between the monitor and the signal source. So, an article on HDMI as an interface itself should be unrelated of HDCP, thus I find the quote "a PC running Windows Vista" misleading. Any PC could use it without HDCP. Am I wrong? - Ioannis Gyftos 146.124.141.250 11:41, 5 November 2007 (UTC) My source: http://groups.google.com/group/comp.os.linux.hardware/browse_thread/thread/ac75fd4c2a0bec2e/41bb694d8cb7f876

HDCP is not a requirement of HDMI. Content protection is a requirement placed by the content owners, and may apply only to certain video modes (e.g., high-definition). One's own video content can be sent without content protection.

PCs can provide HDMI outputs, with or without HDCP support. The mainline graphics card providers - ATi, nVidia and Intel - all provide graphics cards or motherboards with HDMI putputs. I have not kept up on the details, but googling "HDMI graphics card" resulted in this hit: http://www.tweaktown.com/articles/972/three_hdmi_graphics_cards_tested_on_lcd_tv/index.html

Of course, it must be said that these mainline providers may supply only Windows drivers. A search, or inquiries to those companies, should reveal if there are Linux drivers for their graphics solutions.Calbookaddict 15:54, 7 November 2007 (UTC)

The Linux kernel easily detects an HDMI output as DVI. And since my graphics card apparently isn't responsible for audio, I dont believe that HDMI through windows would be any different. Yesterday I bought that laptop and it works in displaying in my LCD-TV through HDMI. So I'll go ahead and remove the Vista restriction. Could provide photos, but I don't know if that would be convincing. - Ioannis Gyftos 146.124.141.250 09:52, 8 November 2007 (UTC)

[edit] Unclear how DVI signal is helped by using HDMI cables

In the HDMI page it mentions that HDMI cables can carry a DVI signal, via an adapter. Does using the HDMI cable overcome the DVI distance limitation, or are boosters still needed? Does using an HDMI cable have any other effects on a DVI signal? I am curious, but would also find this useful for the articles in question. --Alphastream 03:33, 3 November 2007 (UTC)

HDMI has the same limitations, but realisticaly its not much of a limitation. I have a good 50 foot run that works perfectly with no signal boosters or anything. --Ray andrew (talk) 21:09, 17 November 2007 (UTC)

[edit] 1440P Confusion

So what is 1440P and what is it used for? This page mentions it and has a link for it but it just redirects you to the hdtv page. Seems kind of pointless to do that considering 1440P is not even mentioned on that page. A page needs to be created specifically for 1440P just like all of the other resolutions already have. Dvferret (talk) 13:40, 10 January 2008 (UTC)

First time I heard about 1440p was back in 2006 when Chi Mei Optoeletronics, a Chinese CE company, said they would come out with a 47" LCD in the second quarter of 2007 that would have it for the native resolution. I don't think it was ever released to consumers and I can't even find a price for it. Currently there is no indication that it will be used in either consumer displays or computer displays. The most recent 1440p news I can think of was when Gateway made a bit of a stink by stating that their WQXGA (2560x1600) computer display was the world's first "Quad-HD" display which was a rather silly claim to make considering how many other WQXGA displays had been released. Also agree with you that the re-direction of 1440p to the HDTV page doesn't make any sense and that 1440p needs to be made into its own page. --GrandDrake (talk) 17:24, 6 May 2008 (UTC)

[edit] Cable costs - explanation?

At my local electronics store the other day I noticed that one brand of cables was separated by bandwidth - the cheaper cables only let you send low resolutions like 720p, but the more expensive ones went up to and past 1080p. Maybe this explains some of the cable cost differences? 138.38.154.9 (talk) 14:15, 14 January 2008 (UTC)

Sometimes it does but not always.Dvferret (talk) 00:38, 14 February 2008 (UTC)

[edit] HDMI Flashing Picture Problem

Digital Rights Management is partially achieved by detecting attempts to circumvent security established for a high-definition session between two devices. For example, a HDMI-jack-equipped DVD player sending a signal to a HDMI-jack-equipped TV over a HDMI cable involves a session during which the two devices continually exchange a security token, thereby permitting detection of the case where a session is hijacked and bits are diverted to a unsecure device. Well, it turns out sometimes this token does not arrive when or as expected. The DVD player and TV combination causes the picture to blink from picture-to-black-to-picture rapidly and continuously. This makes the program material unwatchable. The attempt by the electronics industry, working hand-in-hand with the large media companies, to protect copyright produces an effect that should only be seen by those who are attempting to steal high definition content. Probably because of different interpretations of the HDMI standard, incompatibilities arise that cause the all-or-nothing system to break down. Perhaps this issue deserves coverage in the wiki. Many users encounter this problem and do not know that its root cause is poor management of HDMI and DRM deployment. —Preceding unsigned comment added by 141.156.240.13 (talk) 12:06, 30 March 2008 (UTC)