Semantic Transcoding of Videos by Using Adaptive Quantization

This paper proposes the use of an approach of video transcoding driven by the video content and provided with the adaptive quantization of MPEG standards. Computer vision techniques can extract semantics from videos according with users interests: the video semantics is exploited to adapt the video in order to meet the device’s capabilities and the user’s requirements and preserve the best quality possible. Well assessed video analysis techniques are used to segment the video into objects grouped in classes of relevance to which the user can assign a weight proportional to their relevance. This weight is used to decide the quantization values to be applied in the MPEG-2 encoding to each macroblock. A modified version of the PSNR (Peak Signal-to-Noise Ratio) is used as performance metric and comparative evaluation is reported with respect to other coding standards such as JPEG, JPEG 2000, (basic) MPEG-2, and MPEG-4. Experimental results are provided on different situations, one indoor and one outdoor.

[1]  John R. Smith,et al.  Adapting Multimedia Internet Content for Universal Access , 1999, IEEE Trans. Multim..

[2]  Rita Cucchiara,et al.  Detecting Moving Objects, Ghosts, and Shadows in Video Streams , 2003, IEEE Trans. Pattern Anal. Mach. Intell..

[3]  Andrew B. Watson,et al.  DCT quantization matrices visually optimized for individual images , 1993, Electronic Imaging.

[4]  Anthony Vetro,et al.  Object-based transcoding for adaptable video content delivery , 2001, IEEE Trans. Circuits Syst. Video Technol..

[5]  Rita Cucchiara,et al.  Semantic Video Transcoding Using Classes of Relevance , 2003, Int. J. Image Graph..

[6]  Katashi Nagao,et al.  Semantic Annotation and Transcoding: Making Web Content More Accessible , 2001, IEEE Multim..

[7]  Robert J. Safranek,et al.  Signal compression based on models of human perception , 1993, Proc. IEEE.

[8]  Ajay Divakaran,et al.  Descriptor for spatial distribution of motion activity for compressed video , 1999, Electronic Imaging.

[9]  Ming-Ting Sun,et al.  Motion Vector Refinement for High-Performance Transcoding , 1999, IEEE Trans. Multim..

[10]  Chang Wen Chen,et al.  SNR scalable transcoding for video over wireless channels , 2000, 2000 IEEE Wireless Communications and Networking Conference. Conference Record (Cat. No.00TH8540).

[11]  Antonio Ortega,et al.  Forward-adaptive quantization with optimal overhead cost for image and video coding with applications to MPEG video coders , 1995, Electronic Imaging.

[12]  Peter H. Westerink,et al.  Two-pass MPEG-2 variable-bit-rate encoding , 1999, IBM J. Res. Dev..

[13]  Charilaos Christopoulos,et al.  Video transcoding for universal multimedia access , 2000, MULTIMEDIA '00.

[14]  John R. Smith,et al.  Content-based transcoding of images in the Internet , 1998, Proceedings 1998 International Conference on Image Processing. ICIP98 (Cat. No.98CB36269).

[15]  Rita Cucchiara,et al.  The Sakbot System for Moving Object Detection and Tracking , 2002 .

[16]  Anthony Vetro,et al.  Encoding and transcoding multiple video objects with variable temporal resolution , 2001, ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems (Cat. No.01CH37196).

[17]  Andrew B. Watson,et al.  Perceptual adaptive JPEG coding , 1996, Proceedings of 3rd IEEE International Conference on Image Processing.

[18]  Rita Cucchiara,et al.  Semantic transcoding for live video server , 2002, MULTIMEDIA '02.

[19]  Allen Gersho,et al.  Vector quantization and signal compression , 1991, The Kluwer international series in engineering and computer science.

[20]  Antonio Ortega,et al.  Adaptive quantization without side information using svq and tcq , 1995 .

[21]  Kannan Ramchandran,et al.  Rate-distortion optimal fast thresholding with complete JPEG/MPEG decoder compatibility , 1994, IEEE Trans. Image Process..

[22]  Jenq-Neng Hwang,et al.  Dynamic frame-skipping in video transcoding , 1998, 1998 IEEE Second Workshop on Multimedia Signal Processing (Cat. No.98EX175).

[23]  Neel Sundaresan,et al.  A semantic transcoding system to adapt Web services for users with disabilities , 2000, Assets '00.

[24]  Shih-Fu Chang,et al.  Development of Advanced Image / Video Servers in A Video on Demand Testbed , 1994 .

[25]  Dirk Farin,et al.  Rate distortion optimal adaptive quantization and qoefficient thresholding for MPEG coding , 2002 .

[26]  Ajay Divakaran,et al.  ADAPTIVE TRANSCODING SYSTEM BASED ON MPEG-7 META-DATA , 2000 .

[27]  Rita Cucchiara,et al.  Detecting Moving Objects and their Shadows: an evaluation with the PETS2002 dataset , 2002, eccv 2002.

[28]  Jerome M. Shapiro,et al.  Embedded image coding using zerotrees of wavelet coefficients , 1993, IEEE Trans. Signal Process..