E.14 Polyphonic melody

23.0403GPPRelease 17Technical realization of the Short Message Service (SMS)TS

A Polyphonic melody can be integrated as an extended object in one or more short messages. Informative guidelines for the creation of polyphony content using SP-MIDI [38] are listed in Annex H.

However, in order to guarantee the interoperability with legacy mobile devices which are not able to interpret specific SP-MIDI content, the following considerations shall be taken into account for content creation:

– When content is not provided in SP-MIDI format the presence of the MIP table in polyphonic extended objects is not mandatory. Since a receiving SME supporting polyphonic extended objects may decide to ignore and skip the content of a MIP message by implementing its own note stealing or channel masking strategy when played. However, when SP-MIDI format data is present and the message is stored and subject to potential forwarding, the specific SP-MIDI content shall be kept as received by the SME.

– the additional rhythm channel as specified in clause 3.2 in [38] might not be supported by the receiving SME.

Octet 8..n SMF as defined in [38], [40]

Annex F (informative) : Compression methods for EMS