An encoding device, comprising: a setting unit configured to set reference image generation information used for generation of first reference image information, the first reference image information serving as information related to a first reference image used when a first scalable image of an image having a hierarchical structure is encoded and second reference image information serving as information related to a second reference image of a second scalable image, wherein the first scalable image is an enhancement layer image and the second scalable image is a base layer image; an encoding unit configured to encode the first scalable image using the first reference image, and generate encoded data; and a transmission unit configured to transmit an enhancement stream, said enhancement stream comprising the encoded data generated by the encoding unit, a sequence parameter set including a copy flag, and the reference image generation information set by the setting unit; wherein the setting unit is configured to set information indicating that the second reference image information is used as the first reference image information as the reference image generation information when the first reference image information is identical to the second reference image information, and wherein the setting unit is configured to compare the information indicating that the second reference image information is used as the first reference image information with the copy flag of the sequence parameter set, and when the information indicating that the second reference image information is used as the reference image information does not correspond with the copy flag, the setting unit is configured to supply the information indicating that the second reference image information is used as the first reference image to the transmission unit for transmission in the enhancement stream. a setting unit configured to set reference image generation information used for generation of first reference image information, the first reference image information serving as information related to a first reference image used when a first scalable image of an image having a hierarchical structure is encoded and second reference image information serving as information related to a second reference image of a second scalable image, wherein the first scalable image is an enhancement layer image and the second scalable image is a base layer image; an encoding unit configured to encode the first scalable image using the first reference image, and generate encoded data; and a transmission unit configured to transmit an enhancement stream, said enhancement stream comprising the encoded data generated by the encoding unit, a sequence parameter set including a copy flag, and the reference image generation information set by the setting unit; wherein the setting unit is configured to set information indicating that the second reference image information is used as the first reference image information as the reference image generation information when the first reference image information is identical to the second reference image information, and wherein the setting unit is configured to compare the information indicating that the second reference image information is used as the first reference image information with the copy flag of the sequence parameter set, and when the information indicating that the second reference image information is used as the reference image information does not correspond with the copy flag, the setting unit is configured to supply the information indicating that the second reference image information is used as the first reference image to the transmission unit for transmission in the enhancement stream.