H4M

• Extension: h4m
• Company: Hudson / University of Tsukuba
• Website: http://www.chaos.cs.tsukuba.ac.jp/research/index.html (Japanese)

H4M is game format that uses AOT (Adaptive Orthogonalized Transform) based vector quantization image compression, RACP (Recurrent AC component Prediction) image compression, DHOM (Descrete Hermonic Oscillator Model) frequency inverter, etc.

• HVQM3 is used on Nintendo64 mario party series.
• HVQM4 is used on Nintendo GameCube biohazard series.