This paper proposes two architectures of 2-D discrete wavelet transform (DWT) and inverse DWT (IDWT). The first high-efficiency architecture comprises a transform module, an address sequencer, and a RAM module. The transform module has uniform and regular structure, simple control flow, and local communication. The significant advantages of the single transform module are full hardware-utilization and low-power. The second architecture features parallel and pipelined computation and high throughput. Both architectures are very suitable for VLSI implementation of new-generation image coding/decoding systems, such as JPEG-2000. In the realization of 2-D DWT/IDWT, we focus on a FPGA and VLSI implementation using 4-tap Daubechies filters, which saves power and reduces chip area.