# US 2019/0320198 A1 · Image encoding method and apparatus and image decoding method and apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0320198 A1 - Document ID: US20190320198A1 - Status: Published application - Kind: A1 - Application number: 16/453,863 - Filed: 2019-06-26 - Published: 2019-10-17 - Earliest claimed: 2016-12-27 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Yin ZHAO; Peiyun DI; Lu YU - Web page: https://patentgrep.com/patent/US20190320198A1 ## CPC - H04N 19/105: Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction - H04N 19/577: Motion compensation with bidirectional frame interpolation, i.e. using B-pictures - H04N 19/146: Data rate or code amount at the encoder output - H04N 19/159: Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction - H04N 19/172: the region being a picture, frame or field - H04N 19/39: involving multiple description coding [MDC], i.e. with separate layers being structured as independently decodable descriptions of input picture data - H04N 19/46: Embedding additional information in the video signal during the compression process (H04N19/517, H04N19/68, H04N19/70 take precedence) - H04N 19/573: Motion compensation with multiple frame prediction using two or more reference frames in a given prediction direction - H04N 19/58: Motion compensation with long-term prediction, i.e. the reference frame for a current frame not being the temporally closest one (H04N19/23 takes precedence) - H04N 19/70: characterised by syntax aspects related to video coding, e.g. related to compression standards - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract This disclosure provides an image encoding method and apparatus and an image decoding method and apparatus. For a to-be-encoded image in a to-be-encoded video sequence, a reference image may be selected from at least one knowledge-base image in a knowledge-base image set. In addition, bitstream data of the to-be-encoded image includes identification information used to identify the reference image of the to-be-encoded image. ## Claims ### Claim 1 An image encoding method, comprising: obtaining a to-be-encoded image in a to-be-encoded video sequence and at least one knowledge-base image in a knowledge-base image set; selecting a reference image of the to-be-encoded image from the at least one knowledge-base image, wherein an image in the knowledge-base image set is used as a candidate reference image of an image in the to-be-encoded video sequence; and performing inter-frame encoding on the to-be-encoded image based on the reference image to obtain bitstream data of the to-be-encoded image, wherein the bitstream data of the to-be-encoded image comprises encoded data of the to-be-encoded image and identification information used to identify the reference image. ### Claim 2 (depends on 1) The method according to claim 1, wherein different images in the knowledge-base image set have different identification information. ### Claim 3 (depends on 2) The method according to claim 2, wherein the to-be-encoded video sequence comprises at least two sequence segments, the identification information of the reference image comprises identification information of a reference sequence segment in which the to-be-encoded image is located, the identification information of the reference sequence segment is used to indicate that the reference image is used as a candidate reference image of an image in the reference sequence segment, the reference sequence segment comprises a random access segment in which the to-be-encoded image is located, and the reference sequence segment is any one of the at least two sequence segments. ### Claim 4 (depends on 2) The method according to claim 2, wherein the performing inter-frame encoding on the to-be-encoded image based on the reference image comprises: obtaining a reconstructed image of the reference image based on the reference image; and performing inter-frame encoding on the to-be-encoded image based on the reconstructed image of the reference image, wherein; the identification information of the reference image comprises quality layer information of the reference image, and the quality layer information of the reference image is used to indicate at least one of a resolution of the reconstructed image of the reference image and a bitstream bit rate of the reconstructed image of the reference image. ### Claim 5 (depends on 1) The method according to claim 1, wherein the method further comprises: sending bitstream data of the reference image to a decoder side, wherein the bitstream data of the reference image does not belong to bitstream data of the to-be-encoded video sequence, the bitstream data of the reference image comprises encoded data of the reference image and an image type of the reference image, and the image type of the reference image is used to indicate that the reference image is an image in the knowledge-base image set. ### Claim 6 An image decoding method, comprising: obtaining bitstream data of a to-be-decoded image, wherein the bitstream data of the to-be-decoded image comprises encoded data of the to-be-decoded image and identification information used to identify a reference image of the to-be-decoded image; searching, based on the identification information, a reconstructed-image set for a reconstructed image having the identification information of the reference image, wherein the reconstructed image is a knowledge-base reconstructed image obtained through reconstruction, the knowledge-base reconstructed image is a reconstructed image of an image in a knowledge-base image set, and the image in the knowledge-base image set is used as a candidate reference image of an image in a to-be-decoded video sequence in which the to-be-decoded image is located; and in response to determining that the reconstructed image having the identification information of the reference image is found, performing inter-frame decoding on the encoded data of the to-be-decoded image based on the reconstructed image having the identification information of the reference image, to obtain a reconstructed image of the to-be-decoded image. ### Claim 7 (depends on 6) The method according to claim 6, wherein the method further comprises: in response to determining that the reconstructed image having the identification information of the reference image is not found, obtaining, based on the identification information of the reference image, bitstream data having the identification information of the reference image as bitstream data of the reference image, wherein the bitstream data of the reference image does not belong to bitstream data of the to-be-decoded video sequence, and the bitstream data of the reference image comprises encoded data of the reference image and the identification information of the reference image; performing decoding based on the encoded data of the reference image to obtain a reconstructed image of the reference image, wherein the reconstructed image of the reference image has the identification information of the reference image; and performing inter-frame decoding on the encoded data of the to-be-decoded image based on the reconstructed image of the reference image to obtain a reconstructed image of the to-be-decoded image. ### Claim 8 (depends on 7) The method according to claim 7, wherein the method further comprises: updating the reconstructed-image set by using the reconstructed image of the reference image as a new reconstructed image in the reconstructed-image set. ### Claim 9 (depends on 7) The method according to claim 7, wherein the bitstream data of the reference image comprises an image type of the reference image, and the image type of the reference image is used to indicate that the reference image is an image in the knowledge-base image set. ### Claim 10 (depends on 9) The method according to claim 9, wherein the image type of the reference image and the identification information of the reference image are in a network abstraction layer unit header of a network abstraction layer unit corresponding to the reference image; or the image type of the reference image is a network abstraction layer unit header of a network abstraction layer unit corresponding to the reference image, and the identification information of the reference image is carried in a network abstraction layer slice header of the network abstraction layer unit corresponding to the reference image. ### Claim 11 An image encoding apparatus, comprising: an obtaining unit, configured to obtain a to-be-encoded image in a to-be-encoded video sequence and at least one knowledge-base image from a knowledge-base image set; a selection unit, configured to select a reference image of the to-be-encoded image from the at least one knowledge-base image, wherein an image in the knowledge-base image set is used as a candidate reference image of an image in the to-be-encoded video sequence; and an encoding unit, configured to perform inter-frame encoding on the to-be-encoded image based on the reference image to obtain bitstream data of the to-be-encoded image, wherein the bitstream data of the to-be-encoded image comprises encoded data of the to-be-encoded image and identification information used to identify the reference image. ### Claim 12 (depends on 11) The apparatus according to claim 11, wherein different images in the knowledge-base image set have different identification information. ### Claim 13 (depends on 12) The apparatus according to claim 12, wherein the to-be-encoded video sequence comprises at least two sequence segments, the identification information of the reference image comprises identification information of a reference sequence segment in which the to-be-encoded image is located, the identification information of the reference sequence segment is used to indicate that the reference image is used as a candidate reference image of an image in the reference sequence segment, the reference sequence segment comprises a random access segment in which the to-be-encoded image is located, and the reference sequence segment is any one of the at least two sequence segments. ### Claim 14 (depends on 12) The apparatus according to claim 12, wherein that the encoding unit performs inter-frame encoding on the to-be-encoded image based on the reference image comprises: the encoding unit obtains a reconstructed image of the reference image based on the reference image, and performs inter-frame encoding on the to-be-encoded image based on the reconstructed image of the reference image, wherein correspondingly, the identification information of the reference image comprises quality layer information of the reference image, and the quality layer information of the reference image is used to indicate at least one of a resolution of the reconstructed image of the reference image and a bitstream bit rate of the reconstructed image of the reference image. ### Claim 15 (depends on 11) The apparatus according to claim 11, wherein the apparatus further comprises: a sending unit, configured to send bitstream data of the reference image to a decoder side, wherein the bitstream data of the reference image does not belong to bitstream data of the to-be-encoded video sequence, the bitstream data of the reference image comprises encoded data of the reference image and an image type of the reference image, and the image type of the reference image is used to indicate that the reference image is an image in the knowledge-base image set. ### Claim 16 An image decoding apparatus, comprising: an obtaining unit, configured to obtain bitstream data of a to-be-decoded image, wherein the bitstream data of the to-be-decoded image comprises encoded data of the to-be-decoded image and identification information used to identify a reference image of the to-be-decoded image; a search unit, configured to search, based on the identification information of the reference image, a reconstructed-image set for a reconstructed image having the identification information of the reference image, wherein the reconstructed image is a knowledge-base reconstructed image obtained through reconstruction, the knowledge-base reconstructed image is a reconstructed image of an image in a knowledge-base image set, and the image in the knowledge-base image set is used as a candidate reference image of an image in a to-be-decoded video sequence in which the to-be-decoded image is located; and a decoding unit, configured to: in response to determining that the reconstructed image having the identification information of the reference image is found, perform inter-frame decoding on the encoded data of the to-be-decoded image based on the reconstructed image having the identification information of the reference image, to obtain a reconstructed image of the to-be-decoded image. ### Claim 17 (depends on 16) The apparatus according to claim 16, wherein the obtaining unit is further configured to: in response to determining that the reconstructed image having the identification information of the reference image is not found, obtain, based on the identification information of the reference image, bitstream data having the identification information of the reference image as bitstream data of the reference image, wherein the bitstream data of the reference image does not belong to bitstream data of the to-be-decoded video sequence, and the bitstream data of the reference image comprises encoded data of the reference image and the identification information of the reference image; the decoding unit is further configured to perform decoding based on the encoded data of the reference image to obtain a reconstructed image of the reference image, wherein the reconstructed image of the reference image has the identification information of the reference image; and the decoding unit is further configured to perform inter-frame decoding on the encoded data of the to-be-decoded image based on the reconstructed image of the reference image to obtain a reconstructed image of the to-be-decoded image. ### Claim 18 (depends on 17) The apparatus according to claim 17, wherein the apparatus further comprises an update unit, configured to update the reconstructed-image set by using the reconstructed image of the reference image as a new reconstructed image in the reconstructed-image set. ### Claim 19 (depends on 17) The apparatus according to claim 17, wherein the bitstream data of the reference image comprises an image type of the reference image, and the image type of the reference image is used to indicate that the reference image is an image in the knowledge-base image set. ### Claim 20 (depends on 19) The apparatus according to claim 19, wherein the image type of the reference image and the identification information of the reference image are in a network abstraction layer unit header of a network abstraction layer unit corresponding to the reference image; or the image type of the reference image is in a network abstraction layer unit header of a network abstraction layer unit corresponding to the reference image, and the identification information of the reference image is a network abstraction layer slice header of the network abstraction layer unit corresponding to the reference image.