# MediaRecorder with EthoVision XT

[![image.png](https://bookstack.noldus.com/uploads/images/gallery/2023-11/scaled-1680-/NR2cIhPuZB6iCdbq-image.png)](https://bookstack.noldus.com/uploads/images/gallery/2023-11/NR2cIhPuZB6iCdbq-image.png)

## How to record videos for EthoVision XT

You can create videos for use in EthoVision XT in two ways.

- [First create videos in MediaRecorder and then track from video file in EthoVision XT](https://bookstack.noldus.com/link/455#bkmrk-page-title)
- [Control video recording by MediaRecorder with EthoVision XT when you track live](https://bookstack.noldus.com/link/456#bkmrk-page-title)

In both cases, if you work with analog cameras, you must adjust the aspect ratio in EthoVision XT. If you work with digital cameras, this is not necessary.

See [Adjust the video aspect ratio (analog cameras only)](https://bookstack.noldus.com/link/457#bkmrk-page-title)

### Prevent <a name="XREF_Heading_3_Prevent_black"></a>black frames at the start of your videos

To make sure that MediaRecorder waits for an I-frame before it starts recording you can edit the VsSettings file that comes with MediaRecorder. If you do not edit this file, your video may start with black frames and EthoVision will not be able to track the video from the start.

The VsSettings file is installed together with MediaRecorder. You can find the file in C:\\ProgramData\\Noldus\\MediaRecorder\\6.

By default the **ProgramData** folder is a hidden folder. In Windows Explorer on the **View** tab select **Hidden items** in the **Show/hide** section to view the folder.

1. Right-click VsSettings.xml and select **Copy**. Right-click and select **Paste** to make a copy of the file. Keep this copy in case you want to go back to the original settings.
2. Open the VsSettings.xml file in Notepad or a similar text editor.
3. From the **Edit** menu select **Find** and type ‘Wait’ in the search field.[![image.png](https://bookstack.noldus.com/uploads/images/gallery/2023-11/scaled-1680-/Sga7XGLsD0iGz0xP-image.png)](https://bookstack.noldus.com/uploads/images/gallery/2023-11/Sga7XGLsD0iGz0xP-image.png)
4. To make sure that MediaRecorder waits for an I-frame before it starts recording, edit the file and change ‘0’ into ‘1’.[![image.png](https://bookstack.noldus.com/uploads/images/gallery/2023-11/scaled-1680-/5pUKu00bSJcAcZaK-image.png)](https://bookstack.noldus.com/uploads/images/gallery/2023-11/5pUKu00bSJcAcZaK-image.png)
5. Save the file.