A standard PS2 DVD holds roughly 4.7GB of data. A "highly compressed" version uses advanced archiving methods to shrink that footprint significantly.
PS2 (Emulator/Homebrew) File Size Claimed: “Highly Compressed” (under 200MB – a miracle for a 4GB game) Verdict: A masterpiece preserved in a straitjacket. A standard PS2 DVD holds roughly 4