We report the successful implementation of a surface-wave enabled dark-field aperture (SWEDA) directly on a complementary metal-oxide semiconductor sensor pixel ( $2.2\mathrm{\mu }\text{m}$ ). This SWEDA pixel allows predetection cancellation of a uniform coherent background. We show that the signal-to-noise ratio (SNR) of the SWEDA pixel is better than that of a single undressed pixel over a significant range of signal-to-background ratio (SBR). For a small SBR value ( $\mathrm{SBR}=0.001$ , $\text{background intensity}=3.96\mathrm{W}/{\mathrm{m}}^2$ , $\text{integration time}=5\mathrm{ms}$ ), we further demonstrate that a SWEDA pixel can detect a weak localized signal buried in a high background, while conventional postdetection background subtraction cannot (improved $\mathrm{SNR}=2.2$ versus $\mathrm{SNR}=0.26$ ).