Clock Stretching Problem, Definition & Solution
Custom installers need to extend HDMI signals for several reasons – mostly to conceal source devices in an equipment rack that may be 100-200 feet away from that beautiful new UHD projector or display – nobody wants a mess of wires and boxes cluttering their home theater! Installers have come to rely on devices called baluns or extenders which enables them to deliver an aesthetically pleasing system to their customer requiring no more than an iPad to control several unseen sources being displayed – on demand, on that 80 inch flat panel in the living room – and the display is not even visible unless it’s being used. HDBaseT has become the go-to technology to solve this requirement with its “5-Play” capability to carry – 1 – Audio, 2 – Video, 3 – Control Signals, 4 – Ethernet and 5- Power – all over a single CAT6a cable.
So….what’s the issue?
Actual interaction on a Cable Company Website
I am trying to use HDBaseT to run video/sound from the Comcast cable box to a TV. I have found out that the SA and Cisco boxes do not support this. Any other box will work.I called tech support and found out they have Motorola boxes at the Picket St location in Alexandria, VA. I went there only to be told, sorry we can't help you because you have a business account. Okay, sounds dumb, but they set up a truck roll for the next day. He shows up and says sorry we don't install anything but Cisco and SA boxes in this area because the other boxes won't work. When asked why they have Motorola boxes at Pickett St. he played dumb and stuck to his story. Sooooo I call business support and get a great guy on the line who assures me that YES the Motorola boxes will work just fine, they will send another guy out with a note to bring a Motorola box. I just spoke with the tech (the courtesy call which I love) and he is telling me that the Motorola boxes won't work. Who is telling me the truth?????
Hello XXXXX and welcome, Just for the general forum : " HDBaseT, promoted and advanced by the HDBaseT Alliance, is a consumer electronic (CE) and commercial connectivity standard for transmission of uncompressed high-definition video (HD), audio, power, home networking, Ethernet, USB, and some control signals, over a common category (Cat6a or above) cable with a standard connector (RJ45). ". Please refer to this link ( http://www.cepro.com/article/comcast_beta_testing_custom_xfinity_integration_cxi_dealer_program/K296 ) regarding Comcast support of this standard Alliance implementation. It is my understanding that Comcast only supports this on their X1 cable boxes and this is a residential only offering at this time. Hope this helps you out.
The issue is that Cisco and Scientific Atlantic set top boxes have-sub version 1.3 HDMI chips that do not support clock stretching, part of the HDCP handshake and can and will manifest itself as an HDCP issue. If possible, see if the local cable company has a different cable box manufacturer such as Samsung, Motorola, Aries, Pace, etc. These should not have any issues with HDBaseT outputs.
The Issue – Clock Stretching
When HDBaseT extenders are used, they packetize the content and this includes the DDC (Display Data Channel) data at the source, and then reverse the process at the TV. This process causes a delay that can take too long for the sources, such as set-top boxes that are more sensitive to the DDC timing, and will stop HDCP content if the EDID isn’t received in time.
EDID (Extended Display Identification Data) is the data that passes over DDC and tells the source what resolution, refresh rate, color space, etc. that the display will support.
HDCP (High-bandwidth Digital Content Protection) is copy protection for the content being delivered to prevent copying and/or distributing material that is owned by the studios.
Hand-Shake to Communicate. First the source (Set Top Box in this case) will request the HDCP key from the display and validate the data, second the source sends the encrypted audio/video content over the 4 TMDS wire pairs and the decryption keys over the DDC wires.
Some products experience timing issues with the I2C and DDC. There is one pair of wires on an HDMI cable called DDC that supports two types of data (HDCP and EDID). When the timing is not correct and out of sync, these signals collide which results in loss of audio/video, flashing picture, wrong resolution or pink and blue abnormal colors.
Houston, we have a failure to communicate. Devices that do not support “clock-stretching” may result in no picture (or other issues mentioned above) since this was not a requirement until HDMI 1.3 and not all HDMI 1.3 devices support it. HDMI 1.2 is still used in many older set top boxes and it is recommended to update your devices to newer technology. If you suspect you have an incompatible device, check with the manufacturer or service provider to see if they have a firmware update that addresses this problem before changing or replacing your equipment. Unfortunately, the problem is usually hardware. You really want to be installing devices with HDMI 1.3a or higher chipsets if you plan on extending.
Known Affected Products
Cisco Explorer 4742HDC and 8642HDC DVR cable boxes
Cisco RNG150 and RNG200 DVR cable boxes
Scientific Atlanta 8240 and 8300HDC cable boxes provided by Time Warner Cable or Comcast/Xfinity.
Samsung BD-ES6000 Blu-ray player
Zigen actually has a few solutions that will work.
1.All Zigen Matrix switches – if you use any of Zigen’s matrices for switching – connect the STB as a source input to the matrix – there will never be a clock-stretching issue. This includes modular switches with HDBT and HDMI outputs from 4x4 (in 2s) to 16x16 at 4K.
2.All Zigen Distribution Amps (splitters) including the new ZIG-DA14-UHD 18 GBPS will correct the issue if the STB is connected as follows: STBDA14-UHDHDBT TXCAT6a CableHDBT RXTV
3.The ZIG-POE-RXAV HDBaseT Receiver is designed to eliminate the clock stretching issue and can be used as the HDBaseT receiver for almost any HDBaseT transmitter. Zigen transmitters that are compatible include:
Connection: STBàHDBT TXàZIG-POE-RXAVàTV
Note: The ZIG-POE-RXAV includes other great features including a 20W per channel stereo amplifier, contact closure relays, Ethernet ports and more.
4.The New ZIG-BF AKA “The Buffer” – can be placed in line with any set up extenders and works up to 18 GBPS (full 4K UHD 2160P60 4:4:4) and has both HDCP correction and EDID management.
So there you go 4 solutions to solve the issue and headaches that follow.
Give us a call at Zigen if you would like additional information on our products and services.
The Zigen Team!
Install with Confidence
For Immediate Release
Zigen is showing and discussing products in a kiosk in the Valens Booth (HDBaseT.org) Hall 5, Stand U92 (5-U92)
Zigen is a leading provider of 4K HDMI connectivity solutions known for its credo "Field Tested - Installer Approved - Install with Confidence!" It's about reliability. No installer can afford go-backs and service calls. Zigen products are designed and engineered in the US and are made for 24/7 flawless operation. We are proud to announce the following products at ISE this year:
HAX-44/HDBT - 4x4 Matrix Switch 18 GPBS w/2 mirrored HDBaseT Ports and Audio Deembedding
Switching for High Value Content Made Simple!
HDMI 2.0 - 600 MHz HDMI matrix switch designed for switching in home and commercial environments where switching of high-value/high-bandwidth UHD (up to 2160P60 4:4:4) content is required. The HAX-44/HDBT features 4 HDMI 2.0 Inputs and 4 HDMI 2.0 outputs. All HDMI and HDBaseT Ports are HDCP 2.2 compliant enabling high value content playback and distribution.
The HAX-44/HDBT includes two 70-meter (228') HDBaseT mirrored ports (ports 2 & 4) with IEEE 802.11af POE (48V) and in compatible with the following receivers: ZIG-HVX-70R, ZIG-POE-RXAV and ZIG-POEWP-R70.
Digital and analog audio de-embedding - with volume control is provided for each output.
For installation and control an Ethernet port and WebOS are included providing access for switching, EDID management, firmware updates, remote reset and 3rd party control and more.
Bi-directional IR - The HAX-44/HDBT is controllable via built in IR receiver. Additionally, full bi-directional IR with IR global routing is included.
Bi-directional RS-232 - A serial connection is provided for 3rd party control connection and device control.
HAX-44/HDBT routes Ethernet and is compliant with the entire Zigen ecosystem of products by routing network commands and control in receiver nodes.
ZIG-SW42 - HDMI 2.0 (18 GBPS) 4x1+1 Switch w/POE, Audio De-embedding and Mirrored HDBaseT
HDMI 2.0 - 600 MHz HDMI switch designed for switching in home and commercial environments where switching of high-bandwidth UHD (2160P60 4:4:4) content is required – or just to be safe for future sources including the new UHD Blu-ray players The SW42 features 4 HDMI 2.0 Inputs and 1 HDMI 2.0 output, digital audio de-embedding of active channel and an Ethernet port and WebOS for setup, switching, EDID management, firmware updates and remote reset. Additionally, the SW42 is controllable via built in IR receiver or RS-232. The SW42 also has a mirrored HDBaseT 100 meter port (single CAT5e of higher). SW42 also routes Ethernet and is compliant with the entire Zigen ecosystem of products by routing network commands and control in receiver nodes.
ZIG-POE-AHTX - HDBaseT Auto-Switch & Extender
HDMI/VGA/CVBS Auto-switching HDBaseT transmitter over single CAT5e/6/7 - 100m, IEEE POE Power Options, 4K, Audio, IR, RS232, LAN - WebOS
The ZIG-POE-AHTX is a 100-meter (328 feet) HDBaseT transmitter. The AHTX has 3 inputs with auto-switching – HDMI, VGA/Component and Composite. With switchable POE it can be set up to power upstream and downstream HDBaseT transmitters and receivers. The ZIG-POE-AHTX can be used stand-alone as an HDBaseT transmitter, but really shines when paired with the ZIG-POE-RXAV receiver/scaler & audio amplifier. A perfect “no-control” control system using “on-connection” technology to fire up projectors, drop screens and control lighting in small rooms – BYOD and in seconds collaborate with your colleagues with full audio and video in stunning 4K UHD. A must for conference rooms and huddle spaces.
ZIG-POEWP-70R HDBaseT Wall Plate Receiver 70 Meter (228') HDBaseT Wall Plate Receiver (RX) with bi-directional IR & RS-232. IEEE POE from HDBaseT TX or 5VDC Local Supply
A perfect "no-control needed" technology
New Zigen HDBaseT receiver is perfect for trim out behind a UHD display or projector in commercial and residential environments – standard 2-gang Decora wall plate. Simply connect up to 70 meters (228’) of category cable from the rack to the ZIG-POE-RX70 and you are all set. Additional capabilities include bi-directional RS232 and IR In and Out ports for added control capabilities. Elegant and cost effective – plus POE or optional 5 VDC direct power.
Not HDBaseT, But Still Ultra Cool
ZIG-BF - (Zigen Buffer) HDMI 2.0(a) - Advanced EDID Manager and Signal Reclocker
The Buffer specifically addresses:
- Clock stretching - corrects problems caused by several STB and BRP that utilize older HDCP chip sets
- Signal buffering & re-clocking - this insures a full strength signal is delivered to the display
- Advanced EDID manager via webOS
- Operation up to 18 GBPS
The ZIG-BF is a 4K60 4:4:4 600MHz 18Gbps capable device built for system integrators to solve the problem of compatibility as new 4K UHD content comes to market. By supporting the max bandwidth and data transfer rate of the HDMI2.0 standard addressing EDID, Clock-Stretching and Re-Clocking the signal before sending it to the display - the Buffer will solve all your UHD headaches. The ZIG-BF will save you time, money and the headache of explaining why the TV you sold to your customer doesn't work.
If you ever connected a UHD Satellite STB, Sony FMP-X10 UHD player or NVidia Shield UHD Netflix account and got the message: “Not Supported" make sure you never see it again with The Buffer!
ZIG-SW41 HDMI 2.0 (18 GBPS) 4x1 Switch w/Audio Deembedding HDMI 2.0 4 x 1 Switch
HDMI 2.0 / HDCP 2.2 / 600 MHz HDMI switch designed for switching in home and commercial environments where switching of high-bandwidth UHD (2160P60 4:4:4) content is required . The SW41-UHD features 4 HDMI 2.0(a) Inputs and 1 HDMI 2.0(a) output, digital audio de-embedding of active channel and an Ethernet port and WebOS for setup, switching, EDID management, firmware updates and remote reset. Additionally, the SW41-UHD is controllable via IR, RS-232 and Ethernet.
ZIG-DA14-UHD - 1x4 HDMI 2.0 Distribution Amplifier
HDMI 2.0 - 600 MHz HDMI distribution amplifier perfect for distributing high bandwidth (2160P60 RGB/4:4:4) HDCP 2.2 content to up to 25 UHD displays (cascading up to 8 units). Weather you need full bandwidth UHD content distributed in a retail environment or home the DA14-UHD-UHD is for you. Robust technology designed and engineered in the USA includes an Ethernet port and WebOS for configuration, EDID management (15 EDID presets & memory for more), and Firmware & Remote reset in a small footprint ½ RU.
ISE 2016 in Amsterdam - RAI Center ISE – 9-12 February Hall 5, Stand 5-U92 (Valens/HDBaseT.org) - For a FREE PASS unse Code: 913694
ZIG-HAVEX - One Bad Ass HDMI 4K Extender!
Just in time for the holidays - Zigen's top of the line 4K Extender and 4-Port POE switch with audio return channel is available to you at a very special price never offered before.
Typical application below:
ZIGEN 6934 Canby Ave Suite 107 Reseda, California 91335 United States
Today I wanted to update you on what's happening at Zigen and why you should start specifying Zigen on your projects. Zigen products are not for everyone - they were specifically designed for you - the professional systems integrator - who is concerned with exceeding customer requirements and demand.
Compliance - HDCP 2.2
Zigen is already HDCP 2.2 compliant on all of their 4K UHD matrices and extenders. From the modular (HX/HDBT 10.2 GBP/Sec Series) to the cutting edge new 18 GBP/Sec products like the HAX-44/HDBT, ZIG-SW42, ZIG-SW41 and ZIG-DA14-UHD.
HAX-44/HDBT HDMI 2.0 Matrix - 18 GBP/Sec HDCP 2.2
Controllable - Driver Support for 4K UHD Implementations
Zigen provides professional control driver support for most of the 3rd party control systems on the market including:
AMX | Crestron | Control 4 | URC | Savant | Bitwise | Elan | RTI
Click on the logos below for a driver request.
Most of the Zigen lineup includes HDBaseT ports - both 70 and 100 meter versions - this makes extending digital and analog signals over long distances with category cable simple and cost effective.
From point to point signal extenders to advanced matrices Zigen can be relied upon to give you the distance at 4K UHD with HDCP 2.2!
True 4K UHD
Our aim is to be true - The 4K (to some of you is a dirty word) rollout has been quite frankly a mess. It's been half baked to say the least.
Resolution - yes, everything for the most part now is running at 2160P (3840x2160) - lighting every pixel on the screen.
But, that's not the end of the story - to get these large signals into the home they have to be compressed over 100:1 to fit through that 15 MBP/Sec (USA average home Internet speed) Internet pipeline. Further there are different frame rates - 30 frames per second, 24, 60, etc. What does this mean to the picture? The quality? Motion artifacts abound today and upscaled 1080P blu-ray still looks better than most streamed 4K native content.
Our aim is to help you make the decisions that best suit your customers requirements on a particular job:
4K UHD HDMI 2.0 with HDCP 2.2 - running at 18 GBP/Sec - These products will produce the best visual and aural experience possible today. Backbones of this level should be employed in your highest end theaters and media rooms. The distances will be short (3-5 meters), and high-quality HDMI cables must be employed. These products can output video resolutions of 2160P60 @ 4:4:4 8-bit or 4:2:2 10-bit HDR.
4K UHD HDMI 2.0/1.4a Hybrid with HDCP 2.2 - running at speeds up to 10.2 GBP/Sec - These are great products for running over extended distances using HDBaseT technology and CAT 5e/6/6a and 7 cables. Solid copper and shielded cables produce the best results. This deployment method produces excellent picture quality but is limited to 2160P60 @ 4:2:0 8-bit, meaning 1/2 of the color pixels are lost in a compression methodology called chroma sub-sampling.
1080P HD HDMI 1.4a and earlier - running between 5-10.2 GBP/Sec - These products have plenty of bandwidth to reproduce excellent quality 1080P content - blu-ray 1080P24 @ 4:2:0 8-bit is native format and it's the same for cable and satellite set top boxes. Computers and gaming devices can output 1080P60 @ 4:4:4/RGB with headroom to spare and especially at the higher frame rates these devices produce less motion artifacts. A great choice for non-critical viewing environments like sports bars, conference rooms, dens, etc.
Zigen manufactures products in all 3 categories and you can find this information easily on our product pages at www.zigencorp.com - while you are visiting check out the CEDIA & Excite Best in Show Products!
In our own research this is not always the case - leading to frustration for integrators.
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