Download the Installation Guide from the DVS-200 product page to get started with DVS-200 for free, by setting up a cloud server droplet and installing the free DVS-100 Mode version of the software.
Audio Sync Drifts
If you experience inconsistent audio sync, meaning the delay varies in length as your stream progresses, you may need to decrease the A/V Sync Interval, which is located in the Settings Menu
If your audio is consistently out of sync, first cross-test it by monitoring the audio on a switcher or production monitor. If that is out of sync as well, then you likely need to add an audio delay box to your audio mixer before feeding it into your switcher or encoder
Bandwidth and Audience Size
Page 2 of the Installation Guide provides guidelines for creating a server to accommodate your audience size, but please keep these additional things in mind:
- Bandwidth is more of a limiting factor that CPU and RAM. All Digital Ocean droplets are connected via a shared 1Gbps pipe. Single droplets that exceed 300Mbps may have their speed throttled.
- If using HLS, it works by downloading "chunks" of video (small video files) as quickly as it can. While a single 2.5Mbps RTMP stream will consume 2.5Mbps constantly, a single 2.5Mbps HLS will consume much more for a short period of time and then nothing until it needs the next chunk.
- HLS makes staying under the 300Mbps limit tricky, so Digital Ocean is not recommended for large audiences, it is ideal for distributing to small audiences, or decoders and external CDN's.
- Most cloud providers perform similarly. Even a dedicated server is not the best solution, because if you have a dedicated server with a 1Gbps connection in the United States, it may not give viewers in other countries the same performance.
- The best solution for large audiences is a CDN like Amazon Cloud Front, where the scale is potentially limitless.
Channel Settings Page Issues
If the channel page does not appear to load correctly and you had set your channel to auto-record, delete some recordings and try again. If you stream 24/7, it is recommend to set your recorder settings to manual start and stop to avoid running out of server disk space.
Delayed Event Playback
The DVS-200 will support this in a future update.
Disabling Pause on the Embedded Player
Set the minimum DVR length greater than the HLS playlist length to disable the player's pause function.
Consider deploying a Compute Optimized EC2 instance, more information is available here via Amazon
Consider deploying an Optimized droplet for video encoding and transcoding, more information is available here via Digital Ocean.
Flashing Stream Name From Red to White in the Live Tab
This means that the incoming RTMP connection is connecting and disconnecting.
Hardware Card Support (for NVS-200 and Custom server builds)
The latest support information for Blackmagic and Datavideo PCIe input cards is located on the last page of the Installation Guide. The Linux Blackmagic drivers are located on their website, and the Datavideo drivers have a download link in the guide.
Please note that the Installation Guide recommends Decklink drivers version 10.8.4, but it is no longer available on the Blackmagic support site. Please use 10.8.5.
Hardware Encoding (for NVS-200 and Custom server builds)
DVS-200 encoding is mostly software based, even when using Blackmagic Decklink cards.
It does not support third-party hardware encoding (Intel Quick Sync, GPUs, etc.) at this time.
If you are using Datavideo's own input cards, they have on board H.264 hardware encoding. They are available in 4x SDI, 8x SDI, and 4x HDMI configurations. Please contact email@example.com for more information.
Datavideo Input Card Video Conversion
Datavideo input/output cards de-interlace video by default, so a 50P source outputs 50P, but a 50i source outputs 25P.
The cards can scale resolution up or down, but not convert frame-rates, which is similar to our NVS-25 encoder.
But if you experience any issues where you only get 59.94 output, please update your card's drivers by running the .DEB package on your server PC.
Please ensure to reboot twice after installing the new driver.
HLS Auto-play on Apple Devices
Devices with iOS and MacOS use Apple's native HLS decoder. Buffering and playback cannot be controlled on these devices, so auto-play is not supported.
If you embed the DVS-200 web player on a website encrypted with HTTPS, you may have playback issues.
To resolve this, you need to install a SSL certificate on your DVS-200 server; this can be uploaded in the system settings.
Please Note: Install the certificate on the DVS-200 using the below options under the main Settings menu.
Assistance with purchasing a SSL certificate is not provided by Datavideo support.
Media Folder Error
If you see the following error along the top of the web user interface:
This means that the Media path does not have write permissions on your Ubuntu installation.
The default path is blank and valid. If you want to change this set, you will need to first set the permissions either via the folder properties in Ubuntu Desktop, or the console.
Third Party Embedded Players
The DVS-200 does not directly support third party web players beyond the one included with the web interface.
If you host a third party player on your own site, you can use the HLS URL from your channel with it.
Streaming to Facebook and YouTube
To output your encoded video to stream to a CDN or services like YouTube Live and Facebook Live, you need to go into the channel settings and in the Outputs section, add Push URL's for each service you want to stream to.
In the above image, when you click on Push URL, you get a window to enter the RTMP URL and Stream Key.
Please note that you generally do not need to enter anything into the Username and Password fields. Do not enter your DVS-200 or streaming service username and password in these fields.
When you click on the blue button under Video, you can set different video settings than your encoder by transcoding, or Passthrough the same settings as the encoder. This is helpful if you want to send 1080P to YouTube and 720P to Facebook at the same time.
The Container should be RTMP. To add another service, click the + button under Action.
Youtube recommends that you set the Audio Bit-rate to 128 Kbps, the GOP Type to Closed GOP, and the Key Interval to 60 or 120 for 30 fps video.
Please note that Facebook Live by default will change your stream key every time you create a new broadcast, please see this article regarding setting a permanent stream key.
Please note that YouTube Live by default may change your stream key periodically. Go back into your YouTube Live channel settings to retrieve the new stream key.
VOD Upload Error
If you try to upload a MP4 or FLV video file and get the following error message:
[File Name] is an invalid file. Only .FLV and .MP4 files are accepted
Go to Settings > Server Settings > Media Storage Directory and change it to a valid location on your server. Please see pages 23-24 of the Configuration Guide for more information about this as well as information on setting up another disk for storage.
Web Player Buffers Frequently
Try increasing the following under the DVS-200 global Settings. Please note that increasing each setting will increase the delay latency for the stream.
Near the bottom of the page:
- HLS Settings > HLS Fragment Length
- HLS Settings > HLS Playlist Length
- HLS Settings > Maximum Buffer Length
- HLS Settings > Maximum Buffer Size
Web Player Will Not Play
It's possible the server is low on disk space due to the size of the system log files. Run the following command via SSH in Terminal:
Then click the Restart All Services butting from the DVS-200 settings page.