A transmission method comprising: dividing a picture into a plurality of regions; generating a plurality of pieces of encoded data that respectively correspond to the plurality of regions by encoding the plurality of regions such that each of the plurality of regions is decodable independently; packetizing the generated plurality of pieces of encoded data into a plurality of packets such that pieces of encoded data for different regions are not stored in a single packet; and transmitting the plurality of packets, wherein adjacent regions of the plurality of regions overlap each other on boundaries of the plurality of regions; wherein each of the plurality of pieces of encoded data has a one-to-one correspondence with a basic data unit, the basic data unit being a unit of data stored in one or more packets, wherein header information of each of the packets includes identification information indicating any one of: only the packet is included in the basic data unit; a plurality of packets are included in the basic data unit, and the packet is a first packet of the basic data unit; a plurality of packets are included in the basic data unit, and the packet is a packet other than the first packet and other than a last packet of the basic data unit; and a plurality of packets are included in the basic data unit, and the packet is the last packet of the basic data unit, wherein the header information of a packet further includes offset information indicating a bit length from a start of encoded data of the picture that includes the plurality of pieces of encoded data to a start of one of the plurality of pieces of encoded data included in the packet. dividing a picture into a plurality of regions; generating a plurality of pieces of encoded data that respectively correspond to the plurality of regions by encoding the plurality of regions such that each of the plurality of regions is decodable independently; packetizing the generated plurality of pieces of encoded data into a plurality of packets such that pieces of encoded data for different regions are not stored in a single packet; and transmitting the plurality of packets, wherein adjacent regions of the plurality of regions overlap each other on boundaries of the plurality of regions; wherein each of the plurality of pieces of encoded data has a one-to-one correspondence with a basic data unit, the basic data unit being a unit of data stored in one or more packets, wherein header information of each of the packets includes identification information indicating any one of: only the packet is included in the basic data unit; a plurality of packets are included in the basic data unit, and the packet is a first packet of the basic data unit; a plurality of packets are included in the basic data unit, and the packet is a packet other than the first packet and other than a last packet of the basic data unit; and a plurality of packets are included in the basic data unit, and the packet is the last packet of the basic data unit, only the packet is included in the basic data unit; a plurality of packets are included in the basic data unit, and the packet is a first packet of the basic data unit; a plurality of packets are included in the basic data unit, and the packet is a packet other than the first packet and other than a last packet of the basic data unit; and a plurality of packets are included in the basic data unit, and the packet is the last packet of the basic data unit, wherein the header information of a packet further includes offset information indicating a bit length from a start of encoded data of the picture that includes the plurality of pieces of encoded data to a start of one of the plurality of pieces of encoded data included in the packet.