There is provided a transmitter by which a reception side easily detects packet loss of a transport packet. The transmitter (1) includes a content dividing unit (13) that divides a set composed of a plurality of units into a plurality of subsets, a transport sequence assigning unit (15) that assigns, to the packet, the transport sequence of the unit within a component and the transport sequence of the unit within the subset, and a header generating unit (14) that generates a packet including the transport sequences.
