3.1.3. Reconstruction Process

The bicubic interpolation was used to upsample the intensity *I low* of the low-resolution RGB image. The size of the patch of the input low-resolution data *Ylow* was *p* = 4, and the overlapping region of adjacent patches was *p* × 1 for the horizontal direction and 1 × *p* for the vertical direction. The filter

size used for the back-projection process was 5 × 5. The sparse representation α was calculated using Equation (12) by solving the L1 norm regularized least-squares problem. We used the code provided by Lee et al. [40].
