Knowledge Base

Problem

When importing a pre-recorded video file into EthoVision and attempting to grab a background image during Arena Setup, the background capture shows only a black or blank screen. The video was not recorded within EthoVision.

Details

Symptom: Background image is black or blank when grabbing from a pre-recorded video. Video may also fail to play back within EthoVision. Cause: The video file uses a codec that EthoVision cannot decode, which is common with videos recorded by third-party software or cameras. A secondary cause can be a corrupt or missing Leadtools component. Affected: Any EthoVision version when using externally recorded video files.

Solution

1. First, try reinstalling the Leadtools component (reinstall Leadtools via the EthoVision installation package or the Noldus-provided installer) and then retry background capture.
2. If that does not resolve it, convert the video to a format EthoVision can reliably read:
a. Download and install Handbrake (free): https://handbrake.fr/
b. On the Summary tab, set Format to MP4.
c. On the Video tab, set the codec to H.264 and the frame rate to 'Same as source.'
d. Use the appropriate quality preset.
3. Import the converted video into EthoVision and retry the background grab.
4. Alternatively, use other conversion tools (e.g., FFmpeg or VirtualDub) targeting H.264 MP4 output.
5. After conversion, verify the video plays correctly in EthoVision before proceeding with arena setup.