Patent ID: 8654840

Claim:
A rate control method of perceptual-based rate-distortion (R-D) optimized bit allocation, comprising: using a coder to perform the steps of: determining an input frame as a key frame; if the input frame is the key frame, additionally encoding the key frame at least one time, thereby generating a corresponding R-D point; updating an R-D model of each basic unit (BU); performing perceptual-based bit allocation, thereby generating a target bit rate for each said BU; computing a quantization parameter (QP) according to the target bit rate; encoding the current BU according to the QP; and updating a rate-quantization (R-Q) model if not all the BUs have been encoded; wherein the R-D model is expressed as D ( R )= αe −βR where R is a bit rate, D is distortion, α and β are model parameters, which are positive; wherein the updated model parameters α* and β* are obtained by minimizing ∑ k = 1  D  ⁢ d ~ k ⁡ ( ln ⁢ ⁢ d ~ k - α - β ⁢ ⁢ r ~ k ) 2 where {tilde over (r)} is encoded bits of the encoded BU, {tilde over (d)} is encoded distortion of the encoded BU, D is a set of data points for updating the R-D model of the BU, and |D| is a number of the data points in D.