Image encoding device and method and image decoding device and method

Abstract

The present disclosure relates to an image encoding device and method and an image decoding device and method, which are capable of suppressing an increase in encoding or decoding workload. A current layer of image data including a plurality of layers is encoded and/or decoded with reference to encoding-related information of some areas, of another layer encoded for each of a plurality of certain areas obtained by dividing a picture, according to control of control information used to control the certain area in which the encoding-related information of the other layer is referred to regarding the current layer of the image data. The present disclosure can be applied to image processing devices such as an image encoding device for performing scalable coding on image data and an image decoding device for decoding an encoded data obtained by performing scalable coding on image data

1 . An image encoding device for encoding image data including a base layer and at least one enhancement layer, the image encoding device comprising:
 a generation section configured to generate control information designating, for a tile of an enhancement layer, a permitted reference area in the base layer, wherein each of the base layer, the at least one enhancement layer, and the permitted reference area comprise one or more tiles, wherein for each of the base layer and the at least one enhancement layer a picture of the image data is divided into the tiles which are independently decodable;   an encoding section configured to encode the tile of the enhancement layer with reference to encoding-related information of the permitted reference area in the base layer according to the control information generated by the generation section; and   a transmission section configured to transmit encoded data of the image data generated by the encoding section and the control information generated by the generation section,   wherein the generation section, the encoding section, and the transmission section are each implemented via at least one processor.   
     
     
         2 . The image encoding device according to  claim 1 ,
 wherein the control information designates the tile of the permitted reference area using an identification number allocated in a raster scan order.   
     
     
         3 . The image encoding device according to  claim 1 ,
 wherein the control information designates the tile of the permitted reference area using information indicating a position of the tile in a picture.   
     
     
         4 . The image encoding device according to  claim 1 ,
 wherein the generation section is further configured to generate information indicating whether or not a tile division of the enhancement layer is similar to a tile division of the base layer.   
     
     
         5 . The image encoding device according to  claim 1 ,
 wherein the generation section is further configured to generate control information determination information serving as information used to control whether or not control information is transmitted, and generate the control information based on the control information determination information.   
     
     
         6 . The image encoding device according to  claim 1 ,
 wherein the transmission section is further configured to transmit information indicating whether or not to control a tile in which the encoding-related information is referred to.   
     
     
         7 . The image encoding device according to  claim 1 ,
 wherein the encoding-related information includes information used for generation of a prediction image used in encoding of the image data.   
     
     
         8 . The image encoding device according to  claim 7 ,
 wherein the information used for the generation of the prediction image includes information used for texture prediction of the image data and information used for syntax prediction of the image data, and   the control information includes information used to independently control a tile in which the information used for the texture prediction is referred to and a tile in which the information used for the syntax prediction is referred to.   
     
     
         9 . The image encoding device according to  claim 1 ,
 wherein the control information designates a tile in which reference to the encoding-related information of the base layer is permitted.   
     
     
         10 . The image encoding device according to  claim 1 ,
 wherein the control information designates a tile in which reference to the encoding-related information of the base layer is prohibited.   
     
     
         11 . The image encoding device according to  claim 1 ,
 wherein the generation section is further configured to generate the control information for each certain tile of a plurality of certain tiles obtained by dividing the picture of the enhancement layer of the image data, and   the encoding section is further configured to encode the enhancement layer of the image data with reference to encoding-related information of some tiles of the base layer for each of the tiles according to control of the control information of each tile generated by the generation section.   
     
     
         12 . An image encoding method for encoding image data including a base layer and at least one enhancement layer, the method comprising:
 generating control designating, for a tile of an enhancement layer, a permitted reference area in the base layer, wherein each of the base layer, the at least one enhancement layer, and the permitted reference area comprise one or more tiles, wherein for each of the base layer and the at least one enhancement layer a picture of the image data is divided into the tiles which are independently decodable;   encoding the tile of the enhancement layer with reference to encoding-related information of the permitted reference area in the base layer according to the control information; and   transmitting encoded data of the image data and the control information.   
     
     
         13 . An image decoding device comprising:
 a reception section configured to
 receive encoded data of a tile of an enhancement layer of image data, the image data including a base layer and at least one enhancement layer, wherein each of the base layer and the at least one enhancement layer comprises one or more tiles, wherein for each of the base layer and the at least one enhancement layer a picture of the image data is divided into the tiles which are independently decodable, and 
 receive control information designating, for the tile of the enhancement layer, a permitted reference area in the base layer, wherein reference to encoding-related information for the permitted reference area for decoding of the encoded data of the tile of the enhancement layer is permitted, wherein the permitted reference area identifies a set of tiles; and 
   a decoding section configured to configured to decode the encoded data with reference to the permitted reference area according to control of the control information received by the reception section,   wherein the reception section and the decoding section are each implemented via at least one processor.   
     
     
         14 . The image decoding device according to  claim 13 ,
 wherein the control information designates the set of tiles using an identification number allocated in a raster scan order, information indicating positions of the tile in vertical and horizontal directions in a picture, or information indicating a data position of the tile in the encoded data.   
     
     
         15 . The image decoding device according to  claim 13 ,
 wherein the reception section is further configured to receive information indicating whether or not to control a tile in which the encoding-related information is referred to.   
     
     
         16 . The image decoding device according to  claim 13 ,
 wherein the encoding-related information includes information used for generation of a prediction image used in decoding of the encoded data.   
     
     
         17 . The image decoding device according to  claim 16 ,
 wherein the information used for the generation of the prediction image includes information used for texture prediction of the image data and information used for syntax prediction of the image data, and   the control information includes information used to independently control a tile in which the information used for the texture prediction is referred to and a tile in which the information used for the syntax prediction is referred to.   
     
     
         18 . The image decoding device according to  claim 13 ,
 wherein the reception section is further configured to receive the encoded data encoded for each of the tiles obtained by dividing the picture of the enhancement layer of the image data and the control information of each of the tiles, and   the decoding section is further configured to decode the encoded data received by the reception section with reference to the encoding-related information of some tiles of the base layer for each of the tiles according to control of the control information of each tile.   
     
     
         19 . The image decoding device according to  claim 13 ,
 wherein the reception section is further configured to receive information indicating whether it is possible to detect a tile division of the enhancement layer with reference to a tile division of the base layer.   
     
     
         20 . The image decoding device according to  claim 13 ,
 wherein the control information designates a tile in which reference to the encoding-related information of the base layer is permitted.   
     
     
         21 . The image decoding device according to  claim 13 ,
 wherein the control information designates a tile in which reference to the encoding-related information of the base layer is prohibited.   
     
     
         22 . The image decoding device according to  claim 13 ,
 wherein the control information designates a tile in which the encoding-related information of the base layer is referred to.   
     
     
         23 . The image decoding device according to  claim 13 ,
 wherein the reception section is further configured to receive control information determination information serving as information used to control whether or not control information is transmitted, and receive the control information based on the control information determination information.   
     
     
         24 . An image decoding method comprising:
 receiving encoded data of a tile of an enhancement layer of image data, the image data including a base layer and at least one enhancement layer, wherein each of the base layer and the at least one enhancement layer comprises one or more tiles, wherein for each of the base layer and the at least one enhancement layer a picture of the image data is divided into the tiles which are independently decodable;   receiving control information designating, for the tile of the enhancement layer, a permitted reference area in the base layer, wherein reference to encoding-related information for the permitted reference area for decoding of the encoded data of the tile of the enhancement layer is permitted, wherein the permitted reference area identifies a set of tiles; and   decoding the encoded data with reference to the permitted reference area according to control of the control information.