| CPC H04N 19/147 (2014.11) [H04N 19/124 (2014.11); H04N 19/172 (2014.11); H04N 19/176 (2014.11); H04N 19/196 (2014.11); H04N 19/61 (2014.11)] | 20 Claims |

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1. A method for complexity constrained encoding of code-streams, including JPEG 2000 and High Throughput JPEG 2000 code-streams, subject to an overall target length constraint, involving the steps of:
a. collecting information about the sub-band samples produced by spatial transformation;
b. generation of coded length estimates from said collected information, for a plurality of potential bit-plane truncation points;
c. determination of a quantization parameter (QP value) from these length estimates, such that after mapping the QP value to a base bit-plane index for each relevant code-block of each sub-band, the estimated overall coded length when truncating at these bit-plane indices is not expected to exceed said overall target length constraint;
d. mapping said QP value to a base bit-plane index for each code-block;
e. encoding each relevant code-block to the precision associated with the corresponding base bit-plane index, and encoding one or more additional coding passes from each such code-block; and
f. subjecting all such generated coding passes to a post-compression rate-distortion optimization process to determine the final set of coding passes emitted from each code-block as the compressed result.
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