An Image Inpainting Method for Interleaved 3D Stacked Image Sensor

This paper presents an image inpainting method for 3D stacked image sensor. A typical structure for 3D stacked image sensor includes a pixel array, an analog-to-digital converter (ADC) array, and an image signal processor (ISP), which are connected vertically by through silicon vias (TSVs) or microbumps (μbumps). To improve the quality of the output images when existing one or more μbump/TSV/ADC failures, it is proposed to interleave the connections from pixel array to ADC array and recover the inaccessible data in the ISP. The sub-array of pixels corresponding to the defective μbump/TSV/ADC would be convenient to be inpainted. An inpainting method used for the damaged block of pixels is proposed, the image is progressively reduced through a process of the discrete wavelet transform (DWT) and down-sampling until the damaged block converts to one pixel only. The reduced image is inpainted and optimized, and then the original image size would be restored by upsampling. Evaluations over a range of images demonstrate that the proposed method improves average peak-signal-to-noise-ratio (PSNR) by 1.93-3.25 dB compared with the exemplar-based method and the TV method in case single or multiple μbump/TSV/ADC defects.