1. Video Transcoding for Wireless Video
Wireless Device Has Limited Resources
Processing power
Memory
Display capability
Change GOP Structure
Save memory
Reduce decoding complexity
Frame Size Down-sampling
Large bit rate reduction
Fit display screens of most
mobile devices
MPEG1/2 to MPEG4
720 x 480
360 x 240

2. Video Transcoding Techniques
Previous Solution [Shanableh & Ghanbari, 00]
Proposed Solution

3. Down-scale Decoder Save More Than 50% of Memory
Reduce Computational Complexity by 70%

4. Experimental Results Average PSNR Degradation is 0.34dB at 384 kb/s
S. Liu, and A. C. Bovik, “A Fast and Memory Efficient Video Transcoder for Low Bit Rate Wireless Communications ”, ICASSP 2002, accepted.