Title :
An efficient use of MPEG-4 FAP interpolation for facial animation at 70 bits/frame
Author :
Lavagetto, Fabio ; Pockaj, Roberto
Author_Institution :
DIST, Genoa Univ., Italy
fDate :
10/1/2001 12:00:00 AM
Abstract :
An efficient algorithm is proposed to exploit the facial animation parameter (FAP) interpolation modality specified by the MPEG-4 standard in order to allow very low bit-rate transmission of the animation parameters. The proposed algorithm is based on a comprehensive analysis of the cross-correlation properties that characterize FAPs, which is here reported and discussed extensively. Based on this analysis, a subset of ten almost independent FAPs has been selected from the full set of 66 low-level FAPs to be transmitted and used at the decoder to interpolate the remaining ones. The performance achievable through the proposed algorithm have been evaluated objectively by means of conventional PSNR measures and compared to an alternative solution based on the increase of the quantization scale factor used for FAP encoding. The subjective evaluation and comparison of the results has also been made possible by uploading mpg movies on a freely accessible Web site. Experimental results demonstrate that the proposed FAP interpolation algorithm allows efficient parameter encoding at around 70 bits/frame or, in other words, at less than 2 kbits/s for smooth synthetic video at 25 frames/s
Keywords :
code standards; computer animation; correlation methods; data compression; interpolation; noise; quantisation (signal); telecommunication standards; video coding; FAP encoding; MPEG-4 FAP interpolation; MPEG-4 standard; PSNR measures; Web site; cross-correlation properties; decoder; efficient algorithm; facial animation; facial animation parameter; movies; quantization scale factor; smooth synthetic video; subjective evaluation; very low bit-rate transmission; Algorithm design and analysis; Decoding; Encoding; Facial animation; Financial advantage program; Interpolation; MPEG 4 Standard; Motion pictures; PSNR; Quantization;
Journal_Title :
Circuits and Systems for Video Technology, IEEE Transactions on