Storer suggested that fast encoders are possible for two-dimensional lossless compression by showing a square greedy matching heuristic for bi-level images, which can be implemented by a simple hashing scheme [2]. The technique is a two-dimensional extension of LZ1 compression. Rectangle matching improves the compression performance, but it is slower since it requires O(M log M) time for a single match, where M is the size of the match [3]. Therefore, the sequential time to compress an image of size n by rectangle matching is \Omega(n log M)