Yoshiaki Shibata

A fast degradation-free algorithm for DCT block extraction in the compressed domain

A fast, degradation-free solution for the DCT block extraction problem is proposed. The problem is defined as extracting a DCT block from a DCT compressed frame composed of DCT blocks. This problem is encountered in both video/image manipulations in the compressed domain and transcodecs, for example, converting from MPEG to Motion JPEG. Traditionally, solutions involve using the pixel domain manipulation or Changs (1992) algorithm with approximations. The new solution expands Changs algorithms, takes full advantage of a fast DCT algorithm, and exploits characteristics of the input DCT blocks without any approximation. The new DCT block extraction achieves 70% performance improvement without any degradation of image quality compared with the conventional solutions.

EssenceMark : SMPTE standard-based textual video marker

EssenceMark* is a simple textual video marker that may be associated with a particular point of interest (POI) in audiovisual essence. This allows a user to quickly access the particular point as desired. EssenceMark is designed based on one of the SMPTE standard-based Key-LengthValue (KLV) metadata items, and thus it can be handled by a wide range of applications and devices that support the relevant standards. This article explains the EssenceMark and its applications.