linear interpolation between wavelet coefficients of two image

hello i have two images called A1 and A2 in different and consecutive time indexes t0 and t1 respectiveley. i want to produce another image between these two in the t=1.5 by interpolating between wavelet coeeficients of the two images. i dont know after wavelet decomposition of each of 2 images, how can i interpolate between for example approximation level of A1 and A2 to produce approximation level od A1.5

clc clear all X=rgb2gray(imread('00000084.jpg')); Y=rgb2gray(imread('00000085.jpg')); %%%decomposition of first image [c1,s1]=wavedec2(X,2,'haar'); [H1,V1,D1] = detcoef2('all',c1,s1,1); A1 = appcoef2(c1,s1,'haar',1); first_image_V1= wcodemat(V1,255,'mat',1); first_image_H1= wcodemat(H1,255,'mat',1); first_image_D1= wcodemat(D1,255,'mat',1); first_image_A1= wcodemat(A1,255,'mat',1); %%%decomposition of second image [c2,s2]=wavedec2(Y,2,'haar'); [H2,V2,D2] = detcoef2('all',c2,s2,1); A2 = appcoef2(c2,s2,'haar',1); second_image_V2 = wcodemat(V2,255,'mat',1); second_image_H2= wcodemat(H2,255,'mat',1); second_image_D2= wcodemat(D2,255,'mat',1); second_image_A2= wcodemat(A2,255,'mat',1);