Real-time software video codec with a fast adaptive motion vector search

A PC-based real-time software MPEG-4 video codec with a fast adaptive motion vector search is presented. In a fast adaptive motion estimation (ME) technique, the search order is dynamically changed in accordance with the motion of objects. This technique suppresses load fluctuation in the ME and contributes to the stable real-time work of the codec. MMX instructions are used to increase the codec speed. On a portable PC, the software video codec supports satisfactory mobile visual communication at 64 kbps and 128 kbps, for example, at QCIF 15 fps. The codec on a 450 MHz Pentium II processor can encode and decode 30 CIF frames in real-time.