Explain the codecs.

The was no accident. For years, 700MB was the capacity of a standard CD-R. Even as people moved to USB drives and hard disks, that 700MB limit remained a "golden rule" for a movie that could be downloaded quickly on a DSL connection. Breaking Down the Technical String

I can help you:

This means the source was a "Blu-ray Rip." Unlike "CAM" versions (recorded in a theater), a BrRip offered crystal-clear source frames.

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