Epiphan screen capture devices

Supported devices

MediaRecorder support the following Epiphan screen capture devices:

• Epiphan DVI2USB 3.0 – A frame grabber device with which you connect the output of the video card of the test computer to a USB 3 port of the recording computer (see also USB 2 and 3 ports). The device has inputs for VGA and DVI signals. It can be connected to a USB 2 or USB 3 port. But it can record with a higher frame rate (up to 30 fps) when connected to a USB 3 port.
• Epiphan VGADVI broadcaster – A frame grabber that streams the output of the video card over Ethernet to the computer with MediaRecorder.

See Set up the VGADVI Broadcaster how to install it and select it in MediaRecorder.

Driver

Use the driver from the MediaRecorder installation USB stick for the following devices:

• Epiphan DVI2USB 3.0

The Epiphan VGADVI broadcaster does not require driver installation.

To install the drivers, choose Epiphan Screen Capture driver in the Drivers and Tools field of the MediaRecorder installation window. Alternatively, browse to Drivers and Tools\Drivers\Epiphan\VGA_DVI2USB\X64 on the MediaRecorder installation USB stick and double-click the file setup.exe.

important  Do not download an update of the driver from the Epiphan website! Otherwise, the screen capture devices may not work properly in combination with MediaRecorder.

Supported setups

The table below shows the maximum supported (1) resolution, (2) frame rate (fps), (3) number of devices and (4) recording time (hours) and (5) whether the test has been carried out on a desktop PC (Dell T3640) or a laptop (3551).

* camera audio = audio over RTSP.

Cable length

USB devices – USB devices can be connected to the computer without an amplifier with a cable of 5 m. For every subsequent 5 m an amplifier must be used. In theory, when using a standard resolution, the cables could be extended to 30 m. However this will not work with a screen capture device. We know that extending the standard 1 m cable with one 5 m cable with amplifier works well with MediaRecorder.

DVI signal – We know that DVI cables of up to 5 m work well with MediaRecorder.

Notes

Audio

To record audio, connect a microphone to the sound card of your computer and select that source in MediaRecorder settings. Although the VGADVI broadcaster can stream audio to MediaRecorder, we know that audio and video will not be synchronous in the video file. Also for this device, record audio with a separate microphone.

Input

All screen capture devices have inputs for different signals like DVI, VGA and HDMI, have only been tested with DVI input.

Frame rate

The actual frame rate of the recorded video is limited by the bandwidth of the screen capture device. It may be much lower than 25-30 frames per second. The  DVI2USB 3 can record with at least 30 fps at high resolution.

Resolution

To record enough screen detail, we recommend to use these devices at high resolution. MediaRecorder supports a resolution of 1920 x 1200. However, screen capture devices by default use the resolution of the screen of the test computer. To change the recorded resolution, change the resolution of the monitor of the test computer.

Set the resolution to fixed

To avoid a change in resolution in the recorded video when the resolution of the test computer changes, you may want to choose a fixed resolution. With fixed resolution images from monitors with a lower or higher resolution will be scaled to the chosen resolution. This is especially useful if you record computer games, since the menu often has another resolution than the game itself. By fixing the resolution you make sure that the entire screen is recorded, even if the resolution of the test computer changes.

Select other frame rate or resolution

For the Epiphan DVI2USB 3.0, Epiphan VGADVI broadcaster, changes you make in MediaRecorder to the frame rate and resolution are not persistent. They are lost when you close and restart MediaRecorder.

Changes you make to the Epiphan AV. io HD are persistent. Select the frame rate and resolution from the lists in the Video Settings window, or select additional options in the Advanced video settings.

See Select a video device

To make persistent changes to the frame rate and resolution in the Epiphan DVI2USB 3.0, Epiphan VGADVI broadcaster, follow the procedure below.

1. Locate the executable v2ugui2.exe. By default this is located in the folder C:\Program Files\Epiphan\Frame Grabber Software.
2. Right-click it and select Properties.
3. Open the tab Compatibility. Under Privilege level, select the checkbox Run this program as an administrator. Ask you system administrator for help if you do not have administrator rights on your computer.
   

   

4. Connect the screen capture device.
5. Open the Epiphan capture tool.
6. Choose Capture > Configure device.
7. Open the tab DirectShow.
8. Select the checkbox next to Fix resolution and choose a resolution from the list.

   

9. Select Limit frame rate to and enter the frame rate.