Layered Depth Image Compression

(a)	(b)
Figure 1. Layered Depth Image, (a) view 1. (b) view 2.

A layered depth image (LDI) is a new popular representation and rendering method for objects with complex geometries. Similar to a 2D image, the LDI consists of an array of pixels. However, unlike the 2D image, an LDI pixel has depth information, and there are multiple layers at a pixel location. Multiple views can be generated from the same LDI image, as shown in Figure 1.

In this project, we develop a novel LDI compression algorithm that handles the multiple layers and the depth coding. The algorithm records the number of LDI layers at each pixel location, and compresses LDI color and depth components separately. The pixels in LDI layer is sparse, the data is aggregated and then encoded. An empirical rate-distortion model is used to optimally allocate bits among different components. Compared with benchmark compression tools such as JPEG-2000 and MPEG-4, our scheme improves the compression performance significantly.

For furthur details of LDI compression, please refer to the related publications:

• J. Duan and J. Li, "Compression of the layered depth image", in Proc. IEEE Data Compression Conference (DCC'2001), Snowbird, Utah, Mar. 2001.
• J. Duan and J. Li, " Compression of the layered depth image ", IEEE Trans. On Image Processing, vol. 12, no. 3, Mar. 2003, pp.365-372.

©Copyright by Jin Li, June 22, 2001