I want to compare the outcome of two different algorithms applied to one set of MRI images. Each MRI image will be manipulated twice. Once using the first algorithm and once using the second algorithm. The data will consists of two groups of values. I want to see if the averages of the two groups are significantly different and I then want to know in what way they are different. Would applying a repeated measure, two-way ANOVA and a post hoc Tukey's test be a valid way of analyzing this data? If not, what tests should I apply?