Patent ID: 7881375
Filing Date: 2011-02-01
Classification: H04N

Abstract:
1. A decoding method for decoding blocks of picture data included in a bit stream, said decoding method comprising: obtaining, by a command obtainment unit and from the bit stream including the blocks of picture data, a sequence of commands for respectively assigning frame-indices, used for frame decoding, to reference frames of the blocks of picture data; adaptively switching, by a processor and on a block-by-block basis of the blocks of picture data, between frame decoding and field decoding; specifying, by a reference frame specification unit and in a case where frame decoding is performed on a block of picture data included in the bit stream, a reference frame, which is referred to when decoding the block of picture data, according to a reference index extracted from a coded block information area of the bit stream and according to a frame-index included in the assigned frame-indices; specifying, by a reference field specification unit and in a case where field decoding is performed on the block of picture data included in the bit stream, a reference field, which is referred to when decoding the block of picture data, according to a reference index extracted from the coded block information area of the bit stream and according to a field-index, which is for field decoding the block of picture data and which is generated using a frame-index included in the assigned frame-indices; obtaining, from the bit stream, information indicating a maximum number of frame-indices; and determining a maximum number of field-indices to be double a value of the maximum number of frame-indices, wherein said specifying of the reference field includes: