Existing discrete cosine transform single-pixel imaging (DCT-SPI) improves the imaging quality, but its number of measurements is twice as the number of pixels of the illumination pattern under full sampling. To reduce the number of measurements, in this letter we propose a single-pixel imaging method called positive discrete cosine transform single-pixel imaging (PDCT-SPI). In the proposed method, only the positive patterns are employed to reconstruct the image. Thus, the number of measurements is reduced by 1/2. Based on the characteristics of Fourier series, the background noise is eliminat...
