Oct 2, 2007 #1 V vadkudr Advanced Member level 4 Joined Jul 12, 2005 Messages 108 Helped 15 Reputation 30 Reaction score 4 Trophy points 1,298 Activity points 2,236 Dear colleagues, Who knows background theory of G.726 codec related to adaptive predictor? Can you describe (or link to) the theory answering to the questions: 1. How the structure of adaptive predictor was developed? 2. How coefficient adaptation rule was developed? a1 (k) = (1 − 2^−8)a1 (k − 1) + (3 · 2^−8) sgn [p (k)] sgn [p (k − 1)] a2 (k) = (1 − 2^−7)a2 (k − 1) + 2^−7 {sgn [p (k)] sgn [p (k − 2)] − f [a1 (k − 1)] sgn [p (k)] sgn [p (k − 1)]} bi (k) = (1 − 2^−9)bi (k − 1) + 2^−7 sgn [dq (k)] sgn [dq (k − i)]. Why these formulas are used?
Dear colleagues, Who knows background theory of G.726 codec related to adaptive predictor? Can you describe (or link to) the theory answering to the questions: 1. How the structure of adaptive predictor was developed? 2. How coefficient adaptation rule was developed? a1 (k) = (1 − 2^−8)a1 (k − 1) + (3 · 2^−8) sgn [p (k)] sgn [p (k − 1)] a2 (k) = (1 − 2^−7)a2 (k − 1) + 2^−7 {sgn [p (k)] sgn [p (k − 2)] − f [a1 (k − 1)] sgn [p (k)] sgn [p (k − 1)]} bi (k) = (1 − 2^−9)bi (k − 1) + 2^−7 sgn [dq (k)] sgn [dq (k − i)]. Why these formulas are used?
Oct 2, 2007 #2 W wwfhm2002 Member level 5 Joined Dec 7, 2003 Messages 83 Helped 6 Reputation 12 Reaction score 5 Trophy points 1,288 Activity points 686 There is an IEEE paper on the history and development of ADPCM, name may be "theory analysis of ADPCM", I don't remember clearly.
There is an IEEE paper on the history and development of ADPCM, name may be "theory analysis of ADPCM", I don't remember clearly.
Oct 3, 2007 #3 V vadkudr Advanced Member level 4 Joined Jul 12, 2005 Messages 108 Helped 15 Reputation 30 Reaction score 4 Trophy points 1,298 Activity points 2,236 do you mean this paper? Theoretical analysis of the ADPCM CCITT algorithm Bonnet, M.; Macchi, O.; Jaidane-Saidane, M. Communications, IEEE Transactions on Volume 38, Issue 6, Jun 1990 Page(s):847 - 858 Digital Object Identifier 10.1109/26.57477
do you mean this paper? Theoretical analysis of the ADPCM CCITT algorithm Bonnet, M.; Macchi, O.; Jaidane-Saidane, M. Communications, IEEE Transactions on Volume 38, Issue 6, Jun 1990 Page(s):847 - 858 Digital Object Identifier 10.1109/26.57477