Userful™: Frequently Asked Questions
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- 1 Installation
- 2 Userful Host
- 2.1 Q: What PCs are compatible with Userful™?
- 2.2 Q: How much content can I store on my Userful server?
- 2.3 Q: What are the different ports used by Userful software appliance?
- 2.4 Q: Can you recommend or sell a compatible rackmount server?
- 2.5 Q: Can Userful be run from a virtualized instance, or a cloud-hosted environment such as Amazon EC2 or Microsoft Azure?
- 3 Zero Clients
- 4 Network Requirements
- 4.1 Q: Does Userful™ require constant Internet connection? Can an Internet connection be over wireless network or cellular modems?
- 4.2 Q: Can I deploy a video wall using a wireless Ethernet connection?
- 4.3 Q: When do I need to use a 10Gbps ethernet uplink?
- 4.4 Q: Can I use server-side scaling for the video wall configuration?
- 4.5 Q: How can I optimize my network?
- 5 Displays
- 5.1 Q: How should I select my displays?
- 5.2 Q: Does Userful appliance support touch screen displays?
- 5.3 Q: What kind of warranty comes with the displays?
- 5.4 Q: What kind of displays can I use to setup my Video Wall? Are professional displays (vs consumer TVs) worth the extra cost?
- 5.5 Q: Will buying 4K displays improve the visual impact and image quality of my video wall?
- 5.6 Q: Can I create a video wall using 4K displays with the Userful solution?
- 5.7 Q: Can I use different displays (sizes and aspect ratios) within the mosaic-style (artistic) video wall (e.g., creating a heterogenous video wall)?
- 6 Nvidia Offload
- 6.1 Q: When do I need an Nvidia Offload Card?
- 6.2 Q: Which Nvidia card is compatible?
- 6.3 Q: Can I use an AMD GPU in place of an Nvidia GPU?
- 6.4 Q: Can I use an Nvidia GT 620, 730, or other similar lower-priced cards?
- 6.5 Q: How do I enable the Nvidia Offload support for content synchronization?
- 6.6 Q: Do I need to restart the Userful host after enabling or disabling the Nvidia Offload Card?
- 6.7 Q: How do I see if the Nvidia Offload Card is in use?
- 7 Control Center
- 7.1 Q: What is the Control Center?
- 7.2 Q: How can I change the language of the Control Center GUI?
- 7.3 Q: How can I create a Control Center launch icon on my mobile device?
- 7.4 Q: Can I control my video wall via a mobile device or laptop?
- 7.5 Q: Can I access the Control Center remotely from over the WAN / Internet?
- 7.6 Q: How can I give users access to control and change the content and/or active session containers on the video wall without giving them access to the Control Center?
- 7.7 Q: Does Userful™ support multi-level permission system? Can I have a separate login for unprivileged staff access where they can control mapping of stations but not admin level functions?
- 7.8 Q: Do I need a specialist to help me with routine configuration of the system?
- 8 Station Mapping
- 8.1 Q: How do I map content to the video wall?
- 8.2 Q: What kind of content can I play on a video wall?
- 8.3 Q: How can I display a Powerpoint presentation on the video wall?
- 8.4 Q: What are the supported video codecs and image formats for Signage Player?
- 8.5 Q: Does your solution support 3D games?
- 8.6 Q: When should I turn on the Mirror Groups feature?
- 9 Network Streamer
- 10 Content Management Solution
- 11 Capture and Playback
- 11.1 Q: Does your solution support multiple HDMI capture cards? What is the upper limit on the number of simultaneous inputs?
- 11.2 Q: Can I mirror my laptop to a video wall in a conference room?
- 11.3 Q: My media player does not have an HDMI output, how can I run it to a video wall?
- 11.4 Q: How can I connect an external media player (PlayStation, Xbox, Apple TV, Chromecast, Laptop) to the video wall?
- 11.5 Q: How can I update firmware for the Blackmagic Capture Card?
- 11.6 Q: Is there any lag time between capture and playback?
- 11.7 Q: Do you support external Apple / Windows / Android / Playstation players?
- 11.8 Q Can I connect an existing matrix switch to the video wall?
- 12 Video Wall
- 12.1 Q: What is a Video Wall?
- 12.2 What is "Artistic" Video Wall?
- 12.3 Q: How do I configure my video wall?
- 12.4 Q: Is Userful’s integrated Color Calibration compatible with displays?
- 12.5 Q: Is 6k playback possible with Userful solution?
- 12.6 Q: How do I create content for an artistic video wall?
- 12.7 Q: Can I choose the size of the canvas for my video wall?
- 12.8 Q: I don’t have any 4K content. Why is it still important to invest in a video wall solution that is capable of playing 4K and higher source content?
- 12.9 Q: When you split 4K content to multiple displays, what filtering and processing are you doing on the scaled image before you send it out?
- 12.10 Q: Can I arrange my displays in an overlapping configuration?
- 12.11 Q: What are the different audio output options for the video wall solution?
- 12.12 Q: Can I use 1080p displays to play 6K or 8K content on my video wall?
- 12.13 Q: How can I get live video from a digital video camera to output to the video wall?
- 12.14 Q: Can the Zones feature display a video in the center of a 2x2 video wall, overlapping the other 4 screens, and have different content played in the unused areas around it?
- 12.15 Q: Can you split / subdivide individual displays into smaller zones?
- 12.16 Q: How can I use input devices such as a keyboard and mouse with the video wall?
- 12.17 Q: If I have an existing display management system (RS232 or Ethernet) how will it interact with Userful?
- 12.18 Q: Can I output multiple content sources on a single video wall screen at the same time?
- 12.19 Q: Does your solution handle blending to send overlapping images to adjacent projectors?
- 12.20 Q: What are the most efficient ways to get content onto the video wall?
- 12.21 Q: What color variation issues can I encounter when viewing a heterogeneous mix of displays (different display models) within a single video wall?
- 13 Virtual Desktop Infrastructure (VDI)
- 13.1 Q: How can I import a Virtual Machine to the Userful host?
- 13.2 Q: What is an OVA file?
- 13.3 How can I clone a Master VM?
- 13.4 Can I use Windows® 10 in the VDI solution?
- 13.5 Can I virtualize Windows 95 and Windows 98 with Userful?
- 13.6 Q: I want to copy file from VM environment to a USB key. How can I achieve this?
- 13.7 Q: My VM is sluggish and unresponsive, can I recreate the Master VM to improve performance?
- 13.8 Q: How do I install Guest Additions after creating a Master VM?
- 13.9 Q: Can I install Userful on a system with Windows Server as a base OS?
- 13.10 Q: Do I require a separate license for the integrated Hypervisor (Oracle VirtualBox)?
- 13.11 Q: Do I require a separate license for the optional Oracle VirtualBox Extensions?
- 13.12 Q: What VDI features depend on having the VirtualBox extensions?
- 13.13 Q: Can I successfully implement the VDI solution without buying the optional VirtualBox Extensions?
- 13.14 Q: Do I need to allocate an IP address for each VM as well as each zero client?
- 14 General
- 14.1 Q: What environments is Userful™ software appliance Ideal for?
- 14.2 Q: Do I need any license or maintenance support for Userful appliance?
- 14.3 Q: What video compression format (H.264/H.265) does your solution send from a Userful host to zero clients?
- 14.4 Q: Professional video wall mounts are expensive, can I just use ordinary TV mounts?
- 14.5 Q: Does the Userful host automatically restrict content playback by enforcing copyright restrictions?
- 14.6 Q: What is a Content Player device?
- 14.7 Q: Does Userful solution support 60fps at 4k and 6k resolution source content?
- 14.8 Q: Does Userful™ support 8k source content?
- 14.9 Q: Does Userful™ support projection mapping?
- 14.10 Q: Does the Userful support TV tuner cards?
- 15 Troubleshooting
Q: Can I install Userful on my Windows PC?
Userful™ is 100% browser managed product. Though the solution is built on Linux, you don't need any Linux expertise to install or manage the solution. Userful cannot be installed on top of Windows, if you want to test it on a PC currently running Windows, you can install it to a separate partition on your hard drive and dual-boot between Windows and Linux.
Q: Can I install Userful™ on my laptop?
Yes, you can install Userful™ on your laptop. However, note that mobile CPUs and GPUs do not offer the same level of performance as a desktop processor and it may not run a 4K video wall. Also, not all power and Wifi functionality may work. Userful™ is designed to run on desktop and server systems.
Q: Do I need to hire any expert to setup Userful?
No, not at all. You don't need any professional installer to setup Userful.
Q: Do I need to preinstall any operating system in my PC to install Userful™ solution?
No. Userful software appliance is integrated with a CentOS 7.2 operating system, it does not need any other operating software.
Q: What PCs are compatible with Userful™?
Please visit Hardware Guide for the complete list of certified PCs.
Q: How much content can I store on my Userful server?
The capacity to store videos and other content locally is limited by the capacity of the system's hard drive. If you need large storage, buy a large multi-terabyte hard disk or if you will be using dynamic content, buy a small capacity SSD drive which will yield faster boot times.
Q: What are the different ports used by Userful software appliance?
For the complete list of ports usage, visit ports used by Userful software appliance.
Q: Can you recommend or sell a compatible rackmount server?
At this time Userful is built to operate on low-cost desktop PC hardware which is readily available from multiple sources. If you are able to procure a rackmount server system compatible with the Hardware Guide, then it should work for your needs. Please note that Xeon CPUs are not tested at this time, though variants that are essentially the same as their desktop i7 counterparts should theoretically work.
Also please note that installing recommended Nvidia Offload Cards or capture cards may not be possible in a rackmount system.
Q: Can Userful be run from a virtualized instance, or a cloud-hosted environment such as Amazon EC2 or Microsoft Azure?
As Userful relies heavily on the CPU and GPU of the hardware on which it is installed, running Userful in a virtualized environment is not recommended or supported.
Zero clients compatible with Userful must be on the same physical 1Gbps+ subnet as their Userful host as they have extremely low tolerance to latency and sub-optimal network conditions.
Q: What is a zero client?
A zero client device is a piece of hardware that connects to a computer and has graphics capability; that is, the device can support a display without requiring another graphics card in the host. Network zero clients connects to the host through a switch or a router using network cables whereas the USB zero clients uses USB cables for connectivity. Check our list of supported zero clients for more details.
Q: Can I use multiple HDMI and VGA displays as outputs for video wall?
Yes. Our recommended zero-client devices include both HDMI and VGA outputs ensuring you can use a broad range of commercial and consumer displays.
Q: Does Userful support a Samsung TV's native network input instead of a zero client device?
This is something we are examining supporting in future. Currently, a supported network zero client is required for each display.
Q: Does Userful™ require constant Internet connection? Can an Internet connection be over wireless network or cellular modems?
No. Userful™ software appliance works fine without an Internet connection, provided all needed content is stored on the local PC. While getting a license key for the system is easier with an Internet connection, you can manage licensing without an Internet connection. If necessary, you can use WiFi or certain types of cellular modems to connect your Userful host to the internet. An internet connection is recommended if you require support from Userful.
Q: Can I deploy a video wall using a wireless Ethernet connection?
Userful™ can accommodate a use case where customers want to deploy a video wall within an existing building that is not wired for Ethernet. The Userful host would be equipped with a wireless card and located close to the video wall itself. In this scenario, it would communicate wirelessly with the LAN but directly (via either a USB connection or wired Ethernet connection with a dedicated switch) with each of the zero clients attached to the video wall displays. The Userful host can be a slim form-factor PC such as an Intel NUC which will fit elegantly behind the video wall displays. Unless your video walls are close to each other you might need a separate Userful host for each video wall. Note: Wireless connection of any sort between the Userful host and the zero clients is not supported.
While most Userful deployments work fine with a common 1Gbps network (including uplink between server and switch), for the high resolution (6K) content or large numbers of displays, the pixel throughput may demand a 10Gbps network card on the Userful host and a 10Gbps uplink port on the switch. When playing content at 30fps, a 10Gbps uplink will be required if:
- your source content is 6k resolution or higher, or
- you are driving more than 25 displays using display-side scaling, or
- you are driving more than 12 displays with server-side scaling or native 1080p playback
Note: Only the uplink port of the switch needs to support 10Gbps, the remaining ports which connect to the zero clients can be 1Gbps. Before finalizing the components of your deployment, contact your Userful representative for pricing and availability of 10Gbps network adapters.
Q: Can I use server-side scaling for the video wall configuration?
By default, the Userful host is configured to use display-scaling that uses the built-in scaler within the display to upscale the image. Almost all displays have a built-in scaler that converts incoming sources to fit their output display size. However, you can switch to "server-side" scaling by disabling the "Display-Scaling" option under Control Center > System Operations. Switching to server-side scaling may improve image quality but increases network bandwidth. Due to increased network bandwidth, we recommend installing a 10Gbps NIC and a switch with 10Gbps uplink port if you have more than 12 displays in your video wall setup.
Q: How can I optimize my network?
To optimize the network, the Userful host and its zero clients should be placed on their own subnet. A second network interface can be installed into the host to allow Userful to create and manage its own completely isolated LAN when connected to its own dedicated switch. No more than 30 zero clients should share the same subnet if they do not uplink to the Userful host with a 10Gbps connection. For optimal performance and reliability, the Userful host and zero clients should be configured with static IPs. It is important to note that the Userful host should NEVER share a subnet with WiFi or other network devices that are not critical to the functionality of Userful. For more details on how to configure dual NICs, visit this link.
Q: How should I select my displays?
Displays can be purchased through Userful, however the solution should be compatible with the vast majority of displays on the market (both commercial and consumer grade). We strongly suggest that you purchase a single display and test, first to ensure full compatibility with the Userful system and that you are happy with the display in regards to mounting and visual appeal. Additional features to look for in a display are auto on/off and locked buttons to prevent the public from interfering with their function.
Q: Does Userful appliance support touch screen displays?
Yes. Please check our list of supported touch screens.
Q: What kind of warranty comes with the displays?
Userful provides a 30-day warranty on displays purchased through Userful. After the initial 30-days the warranty on displays and mounting solutions are provided entirely by the respective manufacturers.
Q: What kind of displays can I use to setup my Video Wall? Are professional displays (vs consumer TVs) worth the extra cost?
Userful™ software appliance allows you to output to virtually any display, and even intermix and color calibrate different makes and sizes of displays within the same video wall. Although substantially more expensive, professional displays do have numerous advantages in terms of features, longevity and warranty. For unattended public displays in 24/7 operation, there is no question that professional displays are recommended. For less demanding setups (e.g., a video wall behind the reception that is under regular staff supervision and is in operation only 8h/day) the substantial cost savings offered through use of consumer TVs are justified.
Q: Will buying 4K displays improve the visual impact and image quality of my video wall?
A high quality 4K display with a high quality upscaler will improve the picture quality a bit over the same content being displayed on an equivalent quality 1080p display. Displays often have built in hardware that uses a process called upscaling to convert incoming sources to fit their output display size (in this case, 4K). Done right, this upscaling combined with the higher pixel count on a 4K display can actually add to the perceived detail of the image, but you will have to look very closely to actually see the difference. Just because a display is 4K doesn't mean it necessarily has a good scaler built in.
Q: Can I create a video wall using 4K displays with the Userful solution?
Yes. Our zero client devices are fully compatible with 4K displays and many of our customers have deployed 4K displays with our zero client devices with great success. Our zero clients output a maximum of 1080p resolution which is then upscaled by the 4K display’s built-in scaler.
Obviously 4K displays cost more, but they do provide better visual results than the equivalent quality 1080p displays. Most customers find the limiting factor on their video wall resolution to be their source content, which for large video walls is typically much smaller than the total possible pixel output of their displays. For example a 2x2 video wall with 4k displays would require an 8k source (which today is feasible only for static images). Perhaps 1% of the video wall controllers in the market are powerful enough to actually drive full frame rate video at 8k or higher resolution.
Q: Can I use different displays (sizes and aspect ratios) within the mosaic-style (artistic) video wall (e.g., creating a heterogenous video wall)?
Yes. Userful's video wall solution can correctly calibrate for different bezels, different models and even different brands of display and can correctly calibrate everything into a single video wall. Userful’s built in color calibration can also help you correct any color discrepancies between displays, even across different makes and models. You should ensure all the selected displays use the same panel technology such as IPS or MVA.
IPS panels provide the best color uniformity and viewing angles. Other technologies can exhibit contrast and gamma shift when viewed at off angles.
Q: When do I need an Nvidia Offload Card?
Userful recommends Nvidia offload card for all video wall configurations. The Nvidia offload card renders higher video and image quality in a scaled video wall with a substantial improvement to synchronization, and can reduce CPU load by as much as 50%. For a complete list of supported cards, visit Nvidia Offload Support.
Q: Which Nvidia card is compatible?
See the list of our tested and certified cards. Generally, 700, 900 and 1000 series Nvidia cards work.
Q: Can I use an AMD GPU in place of an Nvidia GPU?
No, at this time only Nvidia GPUs are supported. An AMD GPU will not actively hinder the system, but currently cannot be used to assist a video wall in any way.
Q: Can I use an Nvidia GT 620, 730, or other similar lower-priced cards?
The GT 620 theoretically supports just one 1080p display, where Intel's HD 4600 GPU can support up to 9. The most cost-effective cards are the GTX 960 for up to 30 displays, or a GTX 980 Ti for up to 60 displays.
Q: How do I enable the Nvidia Offload support for content synchronization?
- Ensure that you have supported Nvidia Offload Card installed in Mid-Range Appliance
- Set the default startup GPU in the BIOS of the Userful host to the Intel® integrated GPU
- You must NOT plug any display onto the Nvidia GPU
- Go to the Control Center > System Operations > Performance Settings Card and enable the Nvidia Offload Card Support
Note: You will need a special license for Nvidia offload support. See Nvidia Offload Support for more information.
Q: Do I need to restart the Userful host after enabling or disabling the Nvidia Offload Card?
Yes, the system will give you the warning message and restart the Userful host automatically when changes are applied.
Q: How do I see if the Nvidia Offload Card is in use?
Open Control Center > System Operations and check the Performance Settings link. You can also check the GPU usage by typing
nvidia-smi command at terminal.
Q: What is the Control Center?
The Control Center is a browser-based management portal used to configure video wall and monitor displays. Its feature include:
- Station Mapping
- Configuring Video Walls
- Network Management
- Display settings
- Station access control
- Virtual Machines
- New package installation and updates
- License management and access to support
Q: How can I change the language of the Control Center GUI?
It is the Browser's preferred language which controls the language of the GUI and not the Userful host's default language. This way multiple administrators can access the system in their preferred language of choice. To change the Control Center's GUI language, please change your browser's settings to select your preferred language.
Q: How can I create a Control Center launch icon on my mobile device?
To create the launch icon:
- Open any web browser on your mobile device and access the Control Center by typing the Userful host's IP address in the address bar
- Click the "Action" button, for iOS and for Android
- Select the "Add to Home Screen" option from the menu
- Edit the name and click the "Add" option. The device will return to the home screen and you will see the icon
Q: Can I control my video wall via a mobile device or laptop?
Yes, If you are on the same LAN you can easily control it through the Control Center. Please visit accessing the Control Center. You can also use the Remote Control feature which allows you to launch and switch between different sessions on stand-alone displays and video wall from any browser using a mobile device, tablet, laptop or a desktop.
Q: Can I access the Control Center remotely from over the WAN / Internet?
If you want to access Control Center from a remote location, we recommend an Internet connection to the site where the displays and Userful appliance are installed with a "static" IP Address (you may need to contact your Internet service provider to obtain this). Alternatively, it is possible to sign up for a dynamic DNS service separately. Then, you will need to enable "port forwarding" on your router and route inbound requests on that specific port to the assigned static IP address of the Userful host. This way you can simply type in the external facing IP address and specified port number (http://IP_Address:port_number) in any browser to connect the Userful Control Center.
Q: How can I give users access to control and change the content and/or active session containers on the video wall without giving them access to the Control Center?
If it is just playlist content that your users want to control, there are two ways to achieve this. You can set a Signage Player playlist to play a directory, and then set up remote access (FTP or Samba file share) and allow the user to copy or remove content from that directory.
Alternatively, most of our customers use one of the supported third party content management solutions to manage content. You can also set the video wall to play an HTML5 web page and use the solution to change and edit the content on that page.
If you want users to be able to switch between session containers, a second approach is to create a Welcome Screen with all the desired session containers available and then use the "Preset Remote Control" feature to launch any session from any device on the same network.
Q: Does Userful™ support multi-level permission system? Can I have a separate login for unprivileged staff access where they can control mapping of stations but not admin level functions?
Yes. Userful™ supports “admin” and “staff” user accounts with different login credentials. Admin login allows full access to all system functions whereas the "staff" login offers restricted access to a limited set of features. Staff users can only map displays to any session container without changing any session settings. For more details, visit staff login section.
Q: Do I need a specialist to help me with routine configuration of the system?
AV specialists are not required for routine configuration changes. Any browser, even a tablet can be used to setup and configure the video-wall in minutes. Drag and drop GUI and intuitive test pattern makes it easy to map appropriate portions of the image to complex artistic display geometries as well as to fine-tune bezel correction in grid layouts. Please visit Configuring Video Wall page for more details.
Q: How do I map content to the video wall?
After creating and calibrating your video wall it will appear in the Control Center > Station Mapping screen. This screen provides the ability to map multiple displays to session containers via a drag and drop interface. The different types of Session Container available are:
- Beabloo Player
- BlackMagic DeckLink Capture
- Cloud Desktop
- DVD Player
- Display5 Player
- Linux Desktop
- Network Streamer
- PADS4 Viewer
- Program Runner
- Remote Desktop Client
- RTP Streamer
- Rise Vision Player
- Signage Player
- Signagelive Player
- TDM Signage
- Video Capture
- Virtual Machines (VDI)
- Web Browsers and Kiosks
Q: What kind of content can I play on a video wall?
Userful's Video Wall feature is very versatile. It supports a broad range of both static and interactive content including:
- Tickers and crawls using RSS or text feeds
- Calendars, clocks, and other widgets (using integrated Content Management Solutions)
- WebGL, HTML5, Flash content
Q: How can I display a Powerpoint presentation on the video wall?
For non-interactive presentations:
- Export your presentation as static jpeg images optimally sized for the video wall, then copy the files to a directory and set them in a directory-based playlist using the Signage Player session container, or
- Export your presentation as a video file (there are various tools online that enable you to do this, including animations and sound), upload it to the Userful host and access it using the Signage Player session container
For interactive sessions:
- Export your presentation as an HTML page using the Web Browser session container, or
- Open your presentation using Office 365 or Office Online using the Web Browser session container, or
- Connect an external laptop running the presentation using the Blackmagic DeckLink Capture or Video Capture session container, or
- Open your presentation using the Windows (VDI) session container
Q: What are the supported video codecs and image formats for Signage Player?
Following content codecs and formats are supported:
- Video Formats: AVI, ASF, MKV, MPG, MP4, OGV, MOV
- Video Codecs: FLAC, AAC, H.264, H.265, DV, MPEG2, Theora, Vorbis, VPX, XviD
- Image Formats: .gif, .pbm, .pgm, .png, .ppm, .qif, .qti, .tif, .tiff, .jpe, .jpg, .jpeg, .qtif, .webp
(Note: The file extension is case sensitive and only lowercase should be used.)
Q: Does your solution support 3D games?
There are several ways to run 3D games:
- Web-based games that use WebGL can simply be run in a Chrome session container (be sure to enable GPU-assisted acceleration)
- Native Linux 3D games running in a Linux Login session container
- Capturing content using an external gaming PC as the source
Q: When should I turn on the Mirror Groups feature?
You should turn on the Mirror Group feature when you want to run the same content on multiple displays or video walls in perfect content synchronization. Please visit Mirror Groups section for more details.
Q: Is Userful's Network Streamer an RTSP client or server?
Currently, Userful™ software appliance provides only RTSP client. If you want to output content from your RTSP server (e.g., webcam or internet streaming service) to your video wall, the Network Streamer container can do that.
Q: Does your solution handle real time camera data streams and resolutions?
We support Real Time Streaming Protocol (RTSP) streams as well as several other streaming protocols and we have tested 1080p RTSP camera streams. We are happy to work with you if you require a specific streaming format or resolution.
Content Management Solution
Q: What types of integrated signage players can we run on the server (without any external media players or HDMI capture cards)?
Currently, we support browser-based content management solutions, including:
- Beabloo Player
- Display5 Player
- PADS4 Viewer
- Rise Vision Player
- Signagelive Player
- TDM Signage
- UIEvolution Player
We are adding additional Content Management Systems all the time. If you have a specific CMS you would like to work with, please let us know.
Q: How do third party plugins work?
Our solution is integrated with a number of content management solutions that are separately licensed or free. Because our solution is built on top of CentOS 7.x (based on RHEL 7.x), skilled Linux administrators have the flexibility to install their own third party plugins and perform additional customization.
Q: Userful doesn’t list my content management system as a supported CMS? Can I still output content to the video wall?
Yes. Content Management System can be integrated with Userful™ using one or more of the options listed below (HDMI capture, Virtual Machine, Browser CMS, Native Plugin). The optimal approach depends on a handful of factors.
- HDMI capture: This approach efficiently offloads the content rendering workload to a separate media player device. Configure your media player and connect it to a capture port on the Userful host instead of connecting it to a display (typically via HDMI). Userful supports both 1080p and 4k multi-port capture cards. This approach adds the cost of the media player and capture card but offers enormous flexibility and creates little to no impact on Userful host system resources because all of the video processing is being done on the external media player.
- Network Streaming: This is similar to the HDMI capture approach, except it eliminates the need for a capture card in the Userful host. Instead of configuring the media player to output a network stream; configure your Userful host to receive this network stream. This typically adds some latency over HDMI capture (which is close to real-time) due to the network encoding and decoding, but saves cost on capture cards and eliminates the distance constraint between your media player and your Userful host.
- Build a Native Userful plug-in: Userful team can work with your content management system vendor to create a plugin for their CMS. Userful often provides the development work for this without charge (provided the CMS meets certain criteria and is keen to participate). The advantage of this approach is it is natively rendered so typically achieves good performance and it eliminates the need for an extra device as mentioned above.
- Manual setup: If your CMS has a browser-based player that works in Firefox or Chrome you can manually set this up and feed parameters such as MAC address as part of the URL.
- Virtual Machine: The CMS can run inside a virtual machine running on the Userful host. This is not ideal from a performance perspective but is possible.
Capture and Playback
Q: Does your solution support multiple HDMI capture cards? What is the upper limit on the number of simultaneous inputs?
Userful supports the Blackmagic DeckLink and YUAN line of HDMI capture cards. The Userful system can handle multiple input cards, limited only by the number of PCIe slots you can fit into your Userful host. You should contact us with details of your project if you intend on using multiple cards ahead of time.
Q: Can I mirror my laptop to a video wall in a conference room?
Yes. However, if you are switching between different laptops throughout the day, this is not a recommended use case as HDMI capture settings may need to be changed with each laptop due to variances in output resolution and color space.
Q: My media player does not have an HDMI output, how can I run it to a video wall?
While the vast majority of modern media players support HDMI output, contact us with your needs and we may be able to advise on the best approach. It is also possible with some Content Management Systems to integrate their player software directly into Userful.
Q: How can I connect an external media player (PlayStation, Xbox, Apple TV, Chromecast, Laptop) to the video wall?
Install a supported capture card, configure the session container and connect any non-HDCP source directly to the capture card.
Q: How can I update firmware for the Blackmagic Capture Card?
To update firmware:
- Open the terminal and type in the following command to check the firmware version (sudo or root privileges are required through out the procedure):
$ sudo BlackmagicFirmwareUpdater status
The output looks something like:
0: /dev/blackmagic/io0 [Intensity Pro 4K] 0x85 OK
Status "OK" represents latest firmware. If the command returns “PLEASE UPDATE”, type the following command and reboot the system:
$ sudo BlackmagicFirmwareUpdater update 0
where "0" represents the capture card number
Q: Is there any lag time between capture and playback?
There could be a negligible lag depending on source media type. However, it can be minimized by lowering the refresh rate of the individual displays.
Q: Do you support external Apple / Windows / Android / Playstation players?
A broad range of external devices can be connected to the Userful host via a capture card. Plug the device directly into the capture card to play the content.
Please Note: HDCP encrypted content playback is not supported.
Q Can I connect an existing matrix switch to the video wall?
Yes, simply plug one of your “output” HDMI cables into the HDMI capture card in the Userful host. The video wall would then become one of your switched outputs. For new installations, it is worth considering building a Userful Host with multiple capture cards and using the Userful host to replace your matrix switch altogether.
Q: What is a Video Wall?
The Video Wall component in Userful™ software appliance is used to send synchronized high-resolution graphical content to an array of displays simultaneously. Typically this is achieved via the "Control Center". Video walls are commonly used in advertising, films, museums, broadcasting. With this solution, a single Userful host is able to output one or more entire video walls over a network.
What is "Artistic" Video Wall?
Sometimes called a mosaic-style video wall, the Userful’s artistic layout available in the “Ultimate” module enables you to intermix different sizes of displays and configure them at any angle to create a truly unique and eye-catching video wall canvas. Userful’s unique and powerful interactive pixel-perfect calibration tool enables you to set up these unique configurations in minutes. Please visit Configuring Video Wall page for more details.
Q: How do I configure my video wall?
Visit the Configuring Video Wall page for detailed instructions.
Q: Is Userful’s integrated Color Calibration compatible with displays?
Color Calibration is achieved by adjusting color values directly at the zero-client chipset level (rather than adjusting settings within the display itself). This design ensures compatibility across a broad range of displays as well as having the further advantage of being able to calibrate color on video walls comprised of a heterogeneous mix of different displays. To learn more about color calibration, visit Configure Video Wall.
Q: Is 6k playback possible with Userful solution?
Yes. For 6k content playback, Userful strongly recommends the Userful certified Mid-Range Appliance. Please visit the Hardware Guide or contact Userful representative for more details.
Q: How do I create content for an artistic video wall?
Userful software appliance is designed to make video wall content creation simple and straightforward. No special steps are required to create content for your artistic video wall. The canvas is the bounding rectangle that encloses all the pixels of all the displays within the video wall. For HTML5 content, the Userful host will launch a browser window of exactly the same height and width as the video wall. You can either create content optimized for this aspect ratio, design the layout of your artistic video wall to match a desired aspect ratio, or use responsive design techniques when building your HTML content so that it adapts cleanly to a variety of aspect ratios. If you are playing video content (e.g., using the Signage Player container), it will play your video centered horizontally and vertically, depending on the scaling option selected (Scale to Fit, Zoom full-screen, or Stretch full-screen).
Q: Can I choose the size of the canvas for my video wall?
Canvas size is dynamically optimized based on the screen resolution (net pixel size including bezels) for interactive sessions. You can also limit the canvas size while configuring zones through Control Center. Our software automatically scales up and scales down the canvas size as required. You could simultaneously play 8k content on a 1080p wall and 1080p content on an 8k wall. You will get the best visual fidelity when your canvas matches your wall, or will be wasting performance when your canvas is bigger than your wall.
Q: I don’t have any 4K content. Why is it still important to invest in a video wall solution that is capable of playing 4K and higher source content?
Installation of a video wall is a very large investment. Userful’s modular approach uses standard PC hardware for the server and standard zero client devices for each screen, ensuring your video wall investment can last for 5 or even 10 years or more. The zero client device lifespan typically exceeds that of your display, and the Userful host can be easily replaced every few years to keep current with the latest hardware advances for a nominal cost. The amount of 4K content is growing exponentially and will increase dramatically in the months and years ahead. While you may not have 4K content today, in a few years, 4K (or higher) will be the expected resolution for newly created content.
Q: When you split 4K content to multiple displays, what filtering and processing are you doing on the scaled image before you send it out?
Both the CPU and GPU are utilized to dynamically perform any scaling, rotation, or cropping required for each of the individual segments of the video wall.
Q: Can I arrange my displays in an overlapping configuration?
Yes, in an artistic video wall you can overlap displays arbitrarily, simply drag the displays on top of each other to create the desired overlap, then fine-tune your alignment using keyboard arrows. In a grid video wall you are allowed uniform vertical or/and horizontal overlapping
Q: What are the different audio output options for the video wall solution?
There are 3 options:
- Pull sound from the sound output jacks on the Userful host. This typically provides the best quality sound output as you can get 5 or even 7 or more channels of sound from a Userful host, as opposed to just stereo sound at the zero client or display itself. This is recommended if sound will be via an overhead centrally controlled audio system which is located in the same room as the Userful host.
- Pull sound from the zero client device via the 3.5mm stereo audio output jack. One device will be designated as the control station for the video wall during creation of the session container and will provide audio output.
- Connect the display with an HDMI cable. This has the same quality as option #2 (stereo) but lets you use speakers built directly into the TV or display.
Q: Can I use 1080p displays to play 6K or 8K content on my video wall?
Yes. Video wall applications always upscale content. Unless you have unusually high-resolution source content (e.g., 8k), or are outputting to an unusually small video wall (e.g., less than 4 1080p displays), the Userful scaling optimizer ensures you won’t miss out on a single pixel of source resolution fidelity whilst balancing CPU and network demands. Userful scales all the way up to 6k and soon 8k source content, with the more typical 4K resolution source files, unless your video wall is less than 4-screens you are also not going to miss out on any resolution.
Up-Scaling (increasing the resolution of the content for output on a high resolution video wall) is a natural part of every video wall technology. The only time you are losing resolution is when you are engaged in down-scaling (for example outputting 8k content to a 2x2 video wall).
Q: How can I get live video from a digital video camera to output to the video wall?
Some webcams output RTSP streams and these can be connected via the Network Streamer session container. Please note this approach would add some latency encoding and decoding will add visually detectable latency to your broadcast.
If you need to achieve imperceptible latency, you’ll need a direct connection between your camera and a capture card in the Userful host. We recommend cameras that outputs via HDMI or SDI streams combined with one of the certified capture cards. If configured correctly this should enable you to capture and relay live video to various screens or video walls connected via network to the Userful host.
Q: Can the Zones feature display a video in the center of a 2x2 video wall, overlapping the other 4 screens, and have different content played in the unused areas around it?
The zones feature allows user to have a video wall playing different content within one layout. To achieve the desired effect you could either setup a 3x3 video wall (with the single monitor in the middle playing different video than the outer ring of 8 displays surrounding it) or a 4x4 video wall (where you could have a 2x2 in the middle).
Alternatively, using one of the integrated content management systems you could achieve the desired effect by mapping a single session container to the entire wall (regardless of size) and control the "picture in picture" zone size within the content management system.
Q: Can you split / subdivide individual displays into smaller zones?
Though not supported directly within Userful, you can achieve the desired result by using various 3rd party content management systems. The Userful "Zones" feature enables individual sources (content management system, live TV, etc.) to span one or more whole displays. Many of the content management solutions which Userful integrates allow you to create and independently address multiple content zones within a single display (e.g. to have tickers across the bottom, etc.). Together these create a literally limitless range of creative possibilities.
Q: How can I use input devices such as a keyboard and mouse with the video wall?
A control station in the video wall configuration is the primary station designated for input and audio capabilities. Plug a keyboard or mouse into the control station's zero client device and make changes. Any action taken to this control station will have the same effect on the video wall as it would on an independent display. You can select the control station while configuring zones.
Q: If I have an existing display management system (RS232 or Ethernet) how will it interact with Userful?
The display connects to the zero client device via either the HDMI or VGA port of your display. You could still use an Ethernet or RS232 control function using an external control and monitoring system to display monitoring, settings, etc., and in the case of a smart display there is nothing that needs to be installed on the TV or display itself.
Q: Can I output multiple content sources on a single video wall screen at the same time?
Yes. However, currently this functionality is only available via the Linux Login and Cloud Desktop session containers. This enables access to a desktop environment and a full window manager where you can resize and move multiple windows around the screen. Alternatively, you can also use an external source (such as a Windows PC) and capture a real time video feed via the HDMI capture.
Q: Does your solution handle blending to send overlapping images to adjacent projectors?
We can adjust overlap via adjusting for a "negative bezel" creating an overlap region, but currently we don't support blending (as in reducing the intensity in the overlapping region to correct for the double or quadruple light).
Q: What are the most efficient ways to get content onto the video wall?
The most efficient approach is to playback videos directly from the hard drive. Though video content can technically be up to 16,000 pixels in either direction, provided your video content does not exceed 4096 pixels in either direction; it enables the onboard GPU to perform the hardware video decoding, preserving CPU. For video, we recommend h264, MPEG2, or h265 as the codecs with MP4 or avi as the container. To maximize performance create and store your videos on the Userful host to play in a playlist loop. Note: When the same content will be played simultaneously on multiple video walls be sure to use the mirror group feature. This ensures the video is only being decoded/processed once.
The CPU is consumed most when your video wall is mapped to session containers that render the content directly (for example a full-screen browser session or a content management system player). Here the Userful host needs to generate all the pixels in addition to performing all the typical tasks of a video wall controller (splitting and sending content to each display).
Q: What color variation issues can I encounter when viewing a heterogeneous mix of displays (different display models) within a single video wall?
Userful’s solution makes it possible to use a heterogeneous mix of displays in a single video wall. The built-in color calibration tool provides a quick way to correct color settings on individual displays. However, there will always be some situations (such as viewing the wall from different angles) where a slight but detectable color variations can be seen. If a heterogeneous video wall is being viewed from a single angle (e.g., a straight-on view) it is much easier to achieve a uniform color. However, if the video wall is set up such that people can walk past it, then viewing angle can change dramatically and pedestrians may notice additional color variations. User needs to determine whether flawless color uniformity from every angle is important than the unique look of having different sizes of panels within the same video wall canvas. If uniformity is important then we suggest using the same panel model (or at least same series).
Virtual Desktop Infrastructure (VDI)
Q: How can I import a Virtual Machine to the Userful host?
To import a VM image, you must first export an existing VM. This can be done directly in VirtualBox, preferably on your personal PC. See VirtualBox's documentation on the topic.
You can then copy the exported .ova file to the “/shared-files” folder of the Userful host (configured via the Control Center), then open Control Center > Virtual Machines, click the “Import VM image” button, and wait for the operation to complete.
Q: What is an OVA file?
An OVA is a Virtual Appliance, or virtual machine, complete with all customization and settings (including memory allocation and network configuration). The most common file format for virtual appliances is Open Virtualization Format (OVF), which is not specific to any system architecture. An OVF package is a directory containing several files; for ease of copying and redistributing, OVF packages are often compressed with the tar utility into a single .ova file.
How can I clone a Master VM?
A key advantage of Userful's design is that cloning is automatic and quick; clones are copied from "known good" virtual machine master images known as Golden Masters. When a Master virtual machine is mapped to a station, a clone is created automatically for each station. Cloned VMs can be viewed and managed within the Oracle VM VirtualBox Manager. For more information, please visit Virtual Machines.
Can I use Windows® 10 in the VDI solution?
Userful has tested and certifies the following operating systems for the VDI solution:
- Windows® 7
- Windows® 8
- Windows® 8.1
- Windows® 10
Can I virtualize Windows 95 and Windows 98 with Userful?
While we don't provide official support for these, depending on your use case and peripheral needs it should be feasible to run the full list of "Community Supported" Guest OSes supported by VirtualBox.
For more info, visit Virtualbox Guest OS Status Page and Forum Virtual Box Veiwtopic. Please note that there are no Guest Additions available for Win95/98, so USB keys and USB pass-thru won't work and you will need to manually set the display resolution of the Windows guest OS to match the selected display size. Other than this, it should likely work for keyboard/video/mouse/audio. If the customer downloads and tests their application running under Win95/98 in VirtualBox (a free download from VirtualBox.org) and it works, then it should work fine using our infrastructure too.
Q: I want to copy file from VM environment to a USB key. How can I achieve this?
USB devices plugged into the zero client device will be automatically passed through to the virtualized Windows environment, but the process is not instantaneous. Please be patient, and avoid repeatedly (and rapidly) plugging and unplugging USB keys as this can cause system instability.
Q: My VM is sluggish and unresponsive, can I recreate the Master VM to improve performance?
Absolutely, as the user who owns the VMs, log onto the Userful host.
- Launch Control Center and navigate to the Virtual Machines tab
- Delete the master VM by clicking the "Delete VM" button under Master Virtual Machines Summary
- Recreate the master VM by clicking Import VM Image button under VM Images in "/shared-files" folder
Once all the stations power back on, the system will begin re-cloning VMs from the recreated master.
Q: How do I install Guest Additions after creating a Master VM?
To install Guest Additions, you must work within a running VM. Login to Linux Desktop as "userful-vdiuser". This is the user account who owns the VM.
- Launch Applications > System Tools > Oracle VM VirtualBox Manager
- Select the Master VM and click "Start"
- Use the VirtualBox Menu Bar and go to Devices > Install Guest Additions
- Follow the on-screen prompts to complete the installation. For detailed help installing Guest Additions, please see VirtualBox documentation.
For a complete list of Guest OSes with supported Guest Additions, visit the VirtualBox Guest OS Status Page.
Q: Can I install Userful on a system with Windows Server as a base OS?
Though this might be technically possible, this is not currently a supported or recommended configuration.
Q: Do I require a separate license for the integrated Hypervisor (Oracle VirtualBox)?
No, the VirtualBox Hypervisor is included and seamlessly integrated into Userful. You don't need to purchase, install, license, or manage it separately. VirtualBox is open-source and licensed under the GPL. Since VirtualBox is cross-platform and available freely, you can download and install a copy of VirtualBox on your Windows, Mac or Linux desktop to create and manage your golden master virtual machine images.
Q: Do I require a separate license for the optional Oracle VirtualBox Extensions?
The VirtualBox extensions are optional but are licensed and distributed directly by Oracle. We link to these extensions within the Control Center, but these are not distributed or included with Userful software appliance. These extensions are covered under Oracle's PUEL license and as clarified in this FAQ. The PUEL enables free Personal, Educational, or Evaluation use. The details are spelled out in the license. Personal and Educational use is quite clear, Commercial evaluation is a bit of a grey area, but basically commercial customers can evaluate the extensions without cost or complexity for a "reasonable period", after which they will need to purchase a commercial license. If you would like to purchase a license for a large commercial deployment you can purchase these either from Userful or from Oracle.
Q: What VDI features depend on having the VirtualBox extensions?
All of the native containers (Browser kiosk, Signage player, Cloud Desktop, etc.) have no requirement for the extensions. The VirtualBox extensions are only helpful when you are running VDI sessions. The features that require the VirtualBox Extensions include:
- Dynamic Desktop Resizing automatically resizes the Windows desktop resolution to match the detected monitor size. Without the VirtualBox extensions, administrators will need to use consistent monitor sizes across all their displays and also manually set the correct display size within their golden master image.
- USB Pass Through Enables USB devices to be accessed directly by the Windows virtual machine. Other USB devices (flash drives, some touch screens, etc.) would not be accessible from within Windows without the extensions.
- Userful Shared Files Storage forwarding enables virtual machine users to access the shared files feature from within Windows. This is useful if you want to automatically enable both Windows and native desktops to read and write from the same shared storage area on the Userful host and manage this storage from within the Control Center. However again administrators who prefer not to use the extensions after the evaluation period can still manually mount the network share within their golden master image.
Q: Can I successfully implement the VDI solution without buying the optional VirtualBox Extensions?
Yes, While the extensions are strongly recommended during initial evaluation, many commercial virtual desktops deployment scenarios work just fine without the extensions. Educational and Personal use customers have free access to the extensions, for commercial customers the decision really comes down to if you need USB key access from within Windows.
Q: Do I need to allocate an IP address for each VM as well as each zero client?
No. Userful can be operated while consuming as few as one IP address within your network for the Userful host. There are several ways of running the zero clients within your network. The Userful host needs to be part of your network, and would require its own IP address. However, it is recommended that you isolate all zero clients to their own subnet. This can easily be done by using a 2nd NIC in the Userful host, and plugging that directly into a dedicated switch that connects all the zero client. The Userful host transparently handles all IP address generation required for operation of the virtual desktops (most of our deployments do actually use NAT for the VMs and it works quite well). With this setup, VMs are isolated from the main network. Of course, from your main network all user-generated Internet traffic for all users will appear to be originating from the single server IP address of the server, but this is typical of most thin client deployments. There are numerous approaches to network setup, but this one is arguably the simplest and cleanest and is the one we recommend for customers who are concerned about minimizing network bandwidth and IP address space.
Q: What environments is Userful™ software appliance Ideal for?
Userful™ software appliance is ideal for signage installations in retail, corporate, entertainment and hospitality environments as well as control room video wall solutions in security, process control, and transportation.
Q: Do I need any license or maintenance support for Userful appliance?
Though you can evaluate Userful software in trial mode, a purchased software license is required for deployment. Maintenance and support is an optional (but recommended) extra service which can be purchased that entitles you to free software updates, professional troubleshooting and support from Userful.
Q: What video compression format (H.264/H.265) does your solution send from a Userful host to zero clients?
The encoding is done by our software and is optimized to preserve image quality and network bandwidth while maintaining synchronization. Each zero client device receives a Motion JPEG (MJPEG) stream because using H.264/H.265 would introduce encoding and latency challenges that would not be acceptable for most use cases. Uncompressed video would be far too demanding on the network and endpoint.
Q: Professional video wall mounts are expensive, can I just use ordinary TV mounts?
Though not typically recommended, it is possible on a small video-wall (e.g., a 2x2) to use less expensive TV mounting solutions and save some money. Setup will naturally take longer and there may be some imperfections in alignment so the savings may or may not be justified. For larger video walls (3x3 and larger) we strongly recommend using the Chief or alternative mounting solution designed specifically for video walls. While with a 2x2 you can access each of the 4 TVs from the exposed edges, with a larger video wall it becomes impossible to access individual displays without first removing neighbouring displays which is painfully cumbersome.
Q: Does the Userful host automatically restrict content playback by enforcing copyright restrictions?
No. The Userful system itself does not impose any restrictions on what content can or cannot be displayed. Though other systems such as HDCP do. We leave it up to the user to determine and adhere to any copyright restrictions and ensure fair use (which would be a formidable and quite likely even impossible task to automate). Some might argue that video walls by their nature are a public display, we have actually seen several examples of private personal video wall installations. So even the determination of personal vs public display is not within the bounds of what a system developer could asses.
Q: What is a Content Player device?
Player device is a component of a digital signage system that is responsible for rendering and outputting the digital content (in pixels) to the video card attached to a signage display. The player implements instructions from content management software. With Userful you can either connect an external player (via an HDMI capture card) or in most cases run multiple instances of the player software directly on the Userful server (which reduces costs and facilitates management).
Q: Does Userful solution support 60fps at 4k and 6k resolution source content?
Yes, Userful™ solution supports 60fps for video file playback. The Userful standard appliance is capable of playing a single 4k source at 60fps (and possibly even 2 simultaneous 4k sources at 60fps). It should also be possible to playback 6k at 60fps. Please note that this is applicable only for video file playback. Currently, Userful™ solution does not support 60fps for non-video content. Also, going from 30fps to 60fps doubles the load on the system CPU, offload card, and the network. Visit Nvidia Support for more details.
Q: Does Userful™ support 8k source content?
Yes. Userful™ software appliance supports 8k source content and 30fps for local video playback (Signage Player). Please note that you will need GTX 980Ti installed on the Userful host for 8k video playback. We do anticipate adding 8k support for interactive sources in the future.
Q: Does Userful™ support projection mapping?
Projection mapping is the process of warping or aligning projected images and videos via image processing software to accommodate irregular projection surfaces. This allows real-world objects to be used as projection surfaces, correct for distortions via software. When you project an image onto an arbitrary object you will find that the image appears distorted. For example, if the object has angles (or is rotated relative to the camera) the image will be awkwardly stretched and distorted. With Projection mapping the computer “pre-warps” (maps) the image so it appears undistorted when projected onto the irregular projection surface.
Userful does not currently include projection mapping. However, we do support negative bezel compensation which allows multiple projectors to be stitched together into a single surface. Userful can handle the projection of the already mapped/distorted image, provided you can process the video externally to match the surface.
Q: Does the Userful support TV tuner cards?
Userful™ solution includes Video Capture session container that supports a broad variety of video capture devices supported by V4L (video4linux). V4L is the software commonly used to support TV tuner cards under Linux. However, for V4L to work, a kernel driver is required for the chosen TV tuner card. Since the chipsets in commercially available TV tuner cards changes so quickly, by the time drivers for these cards become available in the Linux kernel, the chipset is no longer commercially available. For this reason, Userful recommends that customers who require live TV use an external TV tuner solution that outputs a video signal (e.g., HDMI) that can be captured by one of our supported HDMI capture card solutions. Though slightly more expensive at the outset, this ends up being a much more supportable solution in the long term.
Q: I’m seeing occasional visible sluggishness when playing large numbers of videos. How should I fix this?
- Use the mirroring feature when playing identical videos to reduce CPU load significantly, or
- Install an Offload Card to double the performance of your Userful host, or
- Check CPU load using "top" command on the terminal to ensure CPU is adequate for the video load. If any of the videos are particularly inefficient consider replacing or re-encoding them, or
- adjust your Userful host to "Skylake" that has significantly more powerful GPU than Broadwell or Haswell system, or
- If any of the videos have a higher than necessary bitrate or frame rate consider re-encoding them using an optimal format
Q: I am seeing license reminder screen even though the system has hardware license. How should I fix this?
Userful host with hardware licensed zero clients will never show license reminder screen.
- Ensure that at least one or more zero clients are connected to the Userful host
- Disable any unused video output on the Userful host (in case of dual head video card)