This paper discusses the bit-rate compression of super high definition images with Discrete Cosine Transform (DCT). Super high definition images with more than 2048×2048 pixels of resolution are introduced as the next generation image category beyond HDTV. In order to develop bit-rate reduction algorithms, an image I/O system for super high definition still images is assembled. A traditional DCT based coding algorithm called Scene Adaptive Coder (SAC) is applied to super high definition images and related problems are clarified. A new coding algorithm is proposed, which takes human visual perception characteristics into consideration, and its coding performance is examined for super high definition images.