1. A video decoding apparatus that executes a decoding processing for input encoded data for each block, comprising: a variable-length decoding portion that decodes a partition structure of a block to be processed from the input encoded data; a predictive image producing portion that produces a predictive image for each partition that is specified by the partition structure; and a transform candidate deriving portion that determines a set of transform candidate that is a set of applicable transforms based on partition shape information, which partition shape information characterizes each partition with respect to at least one of partition size, a feature of partition size, and a layer in the partition structure, the set of applicable transforms being included in a predetermined transform preset, wherein the variable-length-decoding portion decodes a transform selection flag based on the input encoded data and the set of transform candidate as well as decodes a transform coefficient of the block to be processed based on the transform selection flag, the video decoding apparatus further comprises: a prediction residual reconstructing portion that reconstructs a prediction residual by applying inverse transforms to the transform coefficient, the inverse transforms corresponding to transforms, the transforms being specified by the transform selection flag; and a local decoded image producing portion that outputs decoded image data based on the predictive image and the prediction residual, the decoded image data corresponding to the block to be processed, the predetermined transform preset includes a first transform and a second transform having an equal magnitude relation between a longitudinal length and a lateral length in a transform size to that of the first transform and having smaller transform size than that of the first transform, and the transform candidate deriving portion (i) includes th first transform and excludes the second transform from the set of transform candidate when a partition belongs to a predetermined layer that is not a lowermost layer, and (ii) includes the second transform in the set of transform candidate when the partition belongs to a layer lower than the predetermined layer that is not the lowermost layer.