Title :
Low-bit motion estimation with edge enhanced images for lowpower MPEG encoder
Author :
Takagi, Ayuko ; Nishikawa, Kiyoshi ; Kiya, Hitoshi
Author_Institution :
Dept. of Electr. Eng., Tokyo Metropolitan Univ., Japan
Abstract :
This paper proposes a method for improving the image quality when we use low-bit motion estimation (ME) using linear quantization. By using edge enhanced images for quantization, we can increase the accuracy of the low-bit ME and improve the image quality. It is known that using low-bit images for ME is effective on saving power but it slightly degrades image quality. The quality of the encoded image depends on the thresholds for data quantization, and algorithms for determining thresholds are studied. The proposed method uses linear quantization, which simply truncates the least significant bits. This method is simple without any complicated threshold calculations, and the image quality improves as much as the methods with threshold calculations. To evaluate the effectiveness, we simulate results for image quality and estimate the power consumption using synthesis results from a VHDL model motion estimator
Keywords :
edge detection; image coding; image enhancement; motion control; quantisation (signal); VHDL model; data quantization; edge enhanced images; image quality; least significant bits; linear quantization; low-bit motion estimation; lowpower MPEG encoder; power consumption; thresholds; Codecs; Degradation; Encoding; Energy consumption; Image quality; Image sequences; MPEG standards; Motion estimation; Pixel; Quantization;
Conference_Titel :
Circuits and Systems, 2001. ISCAS 2001. The 2001 IEEE International Symposium on
Conference_Location :
Sydney, NSW
Print_ISBN :
0-7803-6685-9
DOI :
10.1109/ISCAS.2001.921118