A Low-Cost High-Quality Adaptive Scalar for Real-Time Multimedia Applications

A novel scaling algorithm is proposed for the implementation of 2-D image scalar. The algorithm consists of a bilinear interpolation, a clamp filter, and a sharpening spatial filter. The bilinear interpolation algorithm is selected due to its having low complexity and high quality. The clamp and sharpening spatial filters are added as pre-filters to solve the blurring and aliasing effects produced by bilinear interpolation. Furthermore, an adaptive technology is used to enhance the effects of clamp and sharpening spatial filters. To reduce memory buffers and computing resources for the very large scale integration (VLSI) implementation, the clamp filter and sharpening spatial filters both convoluted by a 3 × 3 matrix coefficient kernel are combined into a 5 × 5 combined convolution filter. The bilinear interpolation is simplified by the co-operation and hardware sharing technique to reduce computing resource and hardware costs. The VLSI architecture in this paper can achieve 280 MHz with 9.28-K gate counts, and its chip area is 46 418 μm² synthesized by a 0.13 μm CMOS process. Compared with previous techniques, this paper not only reduces gate counts by more than 46.6% and power consumptions by 24.2%, but also improves average quality by over 0.42 dB.