摘要 |
<p>A method comprises encoding an image video sequence into a scalable video coding (SVC, e.g. for High Efficiency Video Coding, HEVC) base layer (BL) and enhancement layer (EL) images, including encoding an enhancement original INTRA image using intra-frame prediction only (as well as at least one other enhancement image, an INTER image, using inter-frame prediction) by: obtaining a residual image as a difference between the enhancement original INTRA image and a decoded corresponding encoded base layer image, the residual comprising blocks of pixels, each having a block type; transforming pixel values for a block into a set of coefficients each having a coefficient type; determining an initial coefficient encoding merit for each coefficient type; selecting coefficients based on the corresponding initial coefficient encoding merit and a predetermined block merit; quantizing selected coefficients into quantized symbols; and encoding the quantized symbols. Also claimed are related methods comprising: residual enhancement image segmentation selection to minimise estimated encoding cost, based on a rate measure; use of a Generalized Residual Inter-Layer Prediction (GRILP) mode; and selection of coefficient types for which a coefficient encoding merit prior to encoding is greater than a predetermined block merit.</p> |