Open AccessThis article is
- freely available
A Low Power CMOS Imaging System with Smart Image Capture and Adaptive Complexity 2D-DCT Calculation
Department of Electrical and Computer Engineering, University of Calgary, AB T2N1N4, Canada
* Author to whom correspondence should be addressed.
Received: 4 February 2013; in revised form: 1 June 2013 / Accepted: 29 July 2013 / Published: 8 August 2013
Abstract: A novel low power CMOS imaging system with smart image capture and adaptive complexity 2D-Discrete Cosine Transform (DCT) is proposed. Compared with the existing imaging systems, it involves the smart image capture and image processing stages cooperating together and is very efficient. The type of each 8 × 8 block is determined during the image capture stage, and then input into the DCT block, along with the pixel values. The 2D-DCT calculation has adaptive computation complexity according to block types. Since the block type prediction has been moved to the front end, no extra time or calculation is needed during image processing or image capturing for prediction. The image sensor with block type decision circuit is implemented in TSMC 0.18 µm CMOS technology. The adaptive complexity 2D-DCT compression is implemented based on Cyclone EP1C20F400C8 device. The performance including the image quality of the reconstructed picture and the power consumption of the imaging system are compared to those of traditional CMOS imaging systems to show the benefit of the proposed low power algorithm. According to simulation, up to 46% of power consumption can be saved during 2D DCT calculation without extra loss of image quality for the reconstructed pictures compared with the conventional compression methods.
Keywords: CMOS imaging system; low power; smart image capture; adaptive complexity DCT
Citations to this Article
Cite This Article
MDPI and ACS Style
Gao, Q.; Yadid-Pecht, O. A Low Power CMOS Imaging System with Smart Image Capture and Adaptive Complexity 2D-DCT Calculation. J. Low Power Electron. Appl. 2013, 3, 267-278.
Gao Q, Yadid-Pecht O. A Low Power CMOS Imaging System with Smart Image Capture and Adaptive Complexity 2D-DCT Calculation. Journal of Low Power Electronics and Applications. 2013; 3(3):267-278.
Gao, Qing; Yadid-Pecht, Orly. 2013. "A Low Power CMOS Imaging System with Smart Image Capture and Adaptive Complexity 2D-DCT Calculation." J. Low Power Electron. Appl. 3, no. 3: 267-278.