AP3 file format is a VS10XX VSOS App from Asprova – an APS (Advanced Planning and Scheduling) system for Microsoft Windows OS. In short, it saves the scheduling project created via Asprova. Naturally, other apps can use files with .ap3 extensions. Just be cautious with AP3 data from unknown sources.
VOB (Video Object) is a digital video container format usually found in DVD video media. VOB contains DVD video, audio, menu, and text data such as subtitles all multiplexed together. It typically includes MPEG-1 Part 2 or MPEG-2 Part 2 video codec encoded with AAC audio. Although this format is free, some copies might be encrypted.
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