Patent ID: 11412241

Abstract:
There are provided mechanisms of guided transcoding. The methods are performed by a decoder, for producing original transform coefficients, and by an encoder, for producing coded delta transform coefficients. A decoding method comprises deriving a predicted residual block. The decoding method comprises transforming the predicted residual block using a forward transform, thereby producing a plurality of original estimated coefficients, the plurality of OECs comprising a first OEC. The decoding method comprises quantizing the plurality of OECs, thereby producing a plurality of quantized estimated transform coefficients comprising a first ETC corresponding to the first OEC. The decoding method comprises selecting a category based on the first OEC. The decoding method comprises decoding a first coded delta transform coefficient (DTC) corresponding to the first OEC, thereby producing a first decoded DTC, wherein the decoding comprises using the selected category to decode the first coded DTC. The decoding method comprises computing a first original transform coefficient by adding the first decoded DTC to the first ETC.