Files with sec file extension are used by the SecPlayer software. They store video data in M-JPEG video format.
SEC file extension - Sony PlayStation PSP GuinXell SecPlayer video
What is sec file? How to open sec files?
The sec file extension is associated with the SecPlayer video player for GuinXell customized Sony Playstation Portable handheld consoles.
The sec file contains video in M-JPEG video format in resolution up to 240x160 and MP3 audio stream.
This sec file type entry was marked as obsolete and no longer supported file format.
This type of file is no longer actively used and is most likely obsolete. This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types (like documents, projects etc.) that were replaced in higher versions of their original programs.