Multimedia applications such as video and image processing are often characterized as computation intensive applications. For these applications the word-length of data and instructions is different throughout the application. Generating hardware architectures is not a straightforward task since it requires a deep word-length analysis in order to properly determine what hardware resources are needed. In this paper we suggest an automated design methodology based on high-level synthesis which takes care of data word- length and interconnection resource cost in order to generate area and power efficient fixed-point architectures for DSP applications. Both ASIC and FPGA technologies are targeted. Experimental results show that our proposed approach reduces area by 6% to 42% on FPGA technology and by 9% to 48 % on ASIC compared to previous approaches. Power saving can reach up to 44% on FPGA technology and 36% on ASIC.