Are you trying to use a (e.g., PS3 Eye) or another input device? With that, I can give you more specific steps.
Extract the contents of the .7z file to a known folder. Run: Open the extracted folder and run opentrack.exe . Cam 3.7z
The 3.7z file is a portable build of opentrack, likely aimed at solving DirectShow-related crashes when using specific cameras. Are you trying to use a (e
Based on your request, I have put together a write-up based on the file and its likely context, based on opentrack-2.3.0-test-20160922-test-dialog-3.7z and related directshow troubleshooting. Write-up: Cam 3.7z File: Cam 3.7z (Compressed Archive) Cam 3.7z
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