Jin Li, Principal Researcher & Manager
Compression Communication and Storage
Fig. 1. (a) Sample region of interest (ROI) of the image being browsed. (b) JPIP identifies the bitstreams of the coefficient blocks that need to be accessed.
Dr. Li was the first to realize an efficient protocol for interactive browsing of large compressed image (compressed by JPEG 2000) over the Internet. At ISO/JPEG Maui Meeting (1999), he has developed and demonstrated to public a scalable JPEG 2000 image browser (VMedia browser), which allows a user to specify a region in a large image both spatially and in desired resolution. The browser then figures out the portion of the compressed bitstream that covers the selected region of interest (ROI), and download only the compressed bitstream required to decode the ROI. Moreover, the download is performed in a progressive fashion so that a coarse view of the ROI can be rendered very quickly and then gradually refined as more and more bitstream arrives. In the case of the switch of ROI, e.g., zooming in/out or panning around, the browser uses existing compressed bitstream in cache to quickly render a coarse view of the new ROI, and in the same time, request a new set of compressed bitstream corresponding to the updated view. The system greatly improves the experience of browsing large images over the slow networks. Work  develops a protocol that breaks scalable coded JPEG 2000 image into small pieces, and stream the pieces over the Internet according to the resolution, the region that the user is viewing the image. It initiated the JPIP standards activity, which became part 9 of the JPEG 2000 suite of standards.
The work has been incorporated into the H.264/SVC video coding standard in the name of motion compensated temporal filtering.