Fig. 6.

Target modified Derenzo phantom is shown in (a). The reconstructed initial pressure distribution with SNR of measurement data being 40 dB using (b) LBP, (c) LTO, and (d) TV regularization. The results obtained using modified guided filter with (b) as guiding image and to be guided image being (c) and (d) are correspondingly given in (e) and (g). The results using the PA-Fuse with one input image being (b) and another being (c) and (d) are correspondingly given in (f) and (h). The RMSE and CNR of these images are correspondingly presented in Table-1. The red arrows in the TV (reconstructed or fused) images show non-uniform background induced artifacts.