A three-layer scheme for M-channel multiple description image coding

A three-layer scheme is developed for M-channel multiple description image coding. In each description, a subset of the source is encoded in the first layer. In the second layer, the remaining subsets are encoded sequentially by predicting from the already encoded subsets. Each description can thus produce a coarse reconstruction of the source. When multiple descriptions are received, a refined reconstruction is obtained by fusing all coarse reconstructions. A third layer is further included to refine the reconstruction when only one description is lost, which dominates when the probability of channel error is low. We first derive the closed-form expressions of the expected distortion of the system for 1-D sources. The proposed scheme is then applied to lapped transform-based image coding, where we formulate and obtain the optimal lapped transform. Image coding results show that the proposed method outperforms other latest schemes.

► A three-layer scheme is developed for M-channel multiple description image coding.
► A subset of the source is encoded at high rate in the first layer.
► The second layer sequentially encodes other subsets using predictive coding.
► The third layer further refines the reconstruction when only one description is lost.
► The closed-form expression of the expected distortion is derived. Application in lapped transform based image coding is presented.