Speaking partner: an ARM7-based multimedia handheld device

We have implemented MP3 audio decoding, speech recognition, and image compression programs for a handheld foreign language learning device, Speaking Partner. The hardware is based on a relatively low-performance RISC CPU, ARM7TDMI. Several previously known software optimization techniques for RISC processors as well as a few algorithm specific optimization methods are employed. The number of clock cycles for the implementation is more significantly reduced by employing block data transfer instructions, rather than by reducing the accuracy of multiplication. The implementation results show that the ARM7 based CPU can conduct multimedia applications in a multi-tasking mode. The power consumption for each activity and each hardware component is also analyzed.