IRN: Invertible Rescaling Networks A minimal implementation of Invertible Rescaling Network and Its Extensions by Xiao et al. PSNR(Y), DIV2K 2x 4x 8x Official 44.32 35.07 30.29 Reproduced 45.53 34.91 30.64 PSNR(Y) means the PSNR is calculated on the Y channel of YCbCr space.