View source for Docs/FAQs/General

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===Userful REST API===
====Q: What languages can I use for Userful REST API?====
With Userful's REST API  you can use any language you want. Userful provides some example code in a variety of languages such as C#, HTML/JavaScript, Java, Python, etc. You can even experiment with calling API calls directly from a web-page using JavaScript (so that users interaction with their web-browser triggers events on the video wall)<br>
Please visit http://api.userful.com to learn more.

====Q: Can we use the Userful REST API to control scheduling?====
'''Yes''' almost everything that could be achieved via interaction with the GUI, can be controlled via the API. The API is real time, so it implements the action upon receipt of the command. This means any control of timing needs to be handled within your API script.

====Q: Is it possible to access the APIs via Userful cloud instead of Control Center? ====

We strongly recommend using APIs locally, within the same LAN. The reason is that Userful Cloud can introduce unnecessary latency and also other points of failure. Userful Cloud can be down for planned maintenance, and your production system might miss a critical call. <br>
It is technically possible to interface to a Userful system via APIs outside of a LAN, but it is not recommended for production systems for the above reasons.

===General===
====Q: What environments is Userful&trade; software appliance Ideal for?====
Userful&trade; 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. Please visit [[Docs/Support_and Maintenance_Renewal_FAQs | Support and Maintenance Renewal FAQs ]] page for more details.

====Q: Do I need to manage licensing through Control Center whenever I modify any licensing attribute?====
'''No'''. Userful will submit the changes in the license server when you request any changes to your current license. You just need to reboot your Userful host and ensure that Userful host is connected with the Internet while rebooting, this will automatically update the license status in your Userful host. But if you need to update the number of displays licensed, Go to <tt>Settings > [[Docs/Settings#Increase_Licensed_Displays |Manage Licensing]]</tt>.

====Q: What video compression format (H.264/H.265) does your solution send from a Userful host to zero clients?====
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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&trade; 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&trade; 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 [[Docs/Nvidia_Offload_Support | Nvidia Support]] for more details.

====Q: Does Userful&trade; support 8k source content?====
'''Yes'''. Userful&trade; software appliance supports 8k source content and 30fps for local video playback ([[Docs/Mapping/Signage Player |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 solution support browser caching. If the browser has downloaded content, will it keep on playing?====
Browser caching simply depends on the type of web content. General web browsers may cache web pages as they preload a big chunk of the site and when you navigate around you are just showing and hiding parts of the same web page, these sites continue to work without an internet connection. Whereas some sites constantly poll the server for new content so they break soon after the internet connection is lost.<br>
Please note: Browser caching will not cache video(s) as they are too large in size.

====Q: Does Userful&trade; 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 [[Docs/Mapping/Video_Capture | Video Capture]] source 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: Does Userful&trade; software appliance work well for presenting social media feeds?====
'''Yes''', There are lot of tools on the internet to display social media feeds in a browser window. Pick the tool that you like the best and then launch a full-screen web browser source on your video wall to get started. <br>

''Hootsuite platform is considered as an example to quote the steps for managing social media (i.e., twitter) ''<br>
Follow the instructions mentioned in the [https://hootsuite.com/resources/hoot-tip/how-to-display-social-messages-at-events-with-hootfeed link] to set up your account and then create and configure [[Docs/Mapping/Web Browser |Web Browser Source]] under <tt>Control Center > Mapping</tt> to get started.

===Troubleshooting===
====Q: I’m seeing occasional visible sluggishness when playing large numbers of videos. How should I fix this?====

* Use the [[Docs/Mapping#Mirror_Group_Configuration |mirroring]] feature when playing identical videos to reduce CPU load significantly, or
* Install an [[Docs/Nvidia Offload Support#Supported_Cards |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 [[Docs/Optimal_Video_Wall_Guidelines#Supported_Video_Codecs_and_Image_formats |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)

====Q: What if I have a problem? How can I troubleshoot my system?====
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The Control Center can help you solve any problem you may encounter. By selecting <tt> Support > [[Docs/Support#Troubleshoot |Troubleshoot a Problem]] </tt> from the Control Center, a navigation tree opens a page with links to relevant documentation. If a problem cannot be solved using Userful's documentation, the best way to receive technical assistance is to [[Docs/Support#Report_a_Problem |Submit a Problem Report]] directly to [[Docs/Support#Contact_Support |Userful Support]] from the Control Center.

===Support and Maintenance===
For all your queries related to Userful&trade; support and maintenance services, please visit [[Docs/Support_and_Maintenance_Renewal_FAQs| Support and Maintenance Renewal FAQs]].

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==Related Links==
* [[Docs/FAQs | Frequently Asked Questions]]
* [[Docs/Help and Support | Help and Support]]
* [[Docs/Support_and_Maintenance_Renewal_FAQs| Support and Maintenance Renewal FAQs]]

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