For the purposes of the present document, the following terms and definitions apply: continuous media: discrete media: scene description:

For the purposes of the present document, the abbreviations given in TR 21.905 and the following apply: 3GP AAC AVC CC/PP CPB DIMS DLS DRM Enhanced aacPlus EXIF GIF HDTV HEVC ITU-T JFIF JPEG MIDI MIME MM MMS MPEG MP4 PIM PSS SBR SP-MIDI SVG UTF-8 VCL XMF

Plain text. Any character encoding (charset) that contains a subset of the logical characters in Unicode [2] shall be used (e.g. US-ASCII [3], ISO-8859-1 [4], UTF-8 [5], Shift_JIS, etc.). Unrecognized subtypes of "text" shall be treated as subtype "plain" as long as the MIME implementation knows how to handle the charset. Any other unrecognized subtype and unrecognized charset shall be treated as "application/octet - stream". Interoperability with SMS text type is according to [23].

If speech is supported, the AMR codec shall be supported for narrow-band speech [26] [40] [41] [42]. The AMR wideband speech codec [27] [43] [44] [45] shall be supported when wideband speech working at 16 kHz sampling frequency is supported. When using speech media type alone, AMR or AMR-WB data is stored according to the file format specified in [32]. Multi-channel sessions shall not be used.

If audio is supported, then one or both of the following two audio codecs should be supported:

• Enhanced aacPlus [49] [50] [51]
• Extended AMR-WB [46] [47] [48]

There is no requirement that a terminal supporting decoding by one of the codecs shall also support encoding by that codec. Specifically, based on the audio codec selection test results Extended AMR-WB is strong for the scenarios marked with blue, Enhanced aacPlus is strong for the scenarios marked with orange, and both are strong for the scenarios marked with green colour in the table below:

Content type	Music	Speech over Music	Speech between Music	Speech
Bit rate
14 kbps mono
18 kbps stereo
24 kbps stereo
24 kbps mono
32 kbps stereo
48 kbps stereo

More recent information on the performance of the codecs based on more recent versions of the codecs can be found in TR 26.936. Enhanced aacPlus decoder is also able to decode MPEG-4 AAC LC content. Extended AMR-WB decoder is also able to decode AMR-WB content. In addition, MPEG-4 AAC Low Complexity and MPEG-4 AAC Long Term Prediction object types [19] may be supported. The maximum sampling rate to be supported by the decoder is 48 kHz. The channel configurations to be supported are mono (1/0) and stereo (2/0).

If synthetic audio is supported, the Scalable Polyphony MIDI (SP-MIDI) content format defined in Scalable Polyphony MIDI Specification [28] and the device requirements defined in Scalable Polyphony MIDI Device 5-to-24 Note Profile for 3GPP [29] should be supported. SP-MIDI content is delivered in the structure specified in Standard MIDI Files 1.0 [31], either in format 0 or format 1. In addition the Mobile DLS instrument format defined in [38] and the Mobile XMF content format defined in [39] should be supported. A MMS client supporting Mobile DLS shall meet the minimum device requirements defined in [38] in section 1.3 and the requirements for the common part of the synthesizer voice as defined in [29] in sections 1.2.1.2. If Mobile DLS is supported, wavetables encoded with the G.711 A-law codec (wFormatTag value 0x0006, as defined in [38]) shall also be supported. The optional group of processing blocks as defined in [39] may be supported. Mobile DLS resources are delivered either in the file format defined in [38], or within Mobile XMF as defined in [39]. For Mobile DLS files delivered outside of Mobile XMF, the loading application should unload Mobile DLS instruments so that the sound bank required by the SP-MIDI profile [29] is not persistently altered by temporary loadings of Mobile DLS files. Content that pairs Mobile DLS and SP-MIDI resources is delivered in the structure specified in Mobile XMF [39]. As defined in [39], a Mobile XMF file shall contain one SP-MIDI SMF file and no more than one Mobile DLS file. MMS clients supporting Mobile XMF must not support any other resource types in the Mobile XMF file. Media handling behaviours for the SP-MIDI SMF and Mobile DLS resources contained within Mobile XMF are defined in [39].

If still images are supported, ISO/IEC JPEG [8] together with JFIF [9] shall be supported. The support for ISO/IEC JPEG only apply to the following two modes:

• mandatory: baseline DCT, non-differential, Huffman coding, as defined in table B.1, symbol 'SOF0' in [8];
• optional: progressive DCT, non-differential, Huffman coding, as defined in table B.1, symbol 'SOF2' [8].

For JPEG baseline DCT, EXIF compressed image file format should also be supported, as defined in [54]. In that case there is no requirement for the MMS client to interpret or present the EXIF parameters recorded in the file.

If bitmap graphics is supported, the following bitmap graphics formats should be supported:

• GIF87a [15];
• GIF89a, [16];
• PNG, [17].

If video is supported, the following applies:

• H.264 (AVC) [52] Constrained Baseline Profile (CBP) Level 1.3 shall be supported.
• H.264 (AVC) [52] High Profile Level 3.1 with frame_mbs_only_flag=1 should be supported by MMS clients supporting HDTV video content at a resolution of 1280x720 (720p) with progressive scan at 30 frames per second. Maximum VCL Bit Rate shall be constrained to 14Mbps by cpbBrVclFactor & cpbBrNalFactor being fixed to 1000 and 1200 respectively, irrespective of the profile. Note that peak Bit Rate is determined by the CPB size.
• H.265 (HEVC) [62] Main Profile, Main Tier, Level 3.1 decoder should be supported. H.265 (HEVC) Main Profile shall be used with general_progressive_source_flag equal to 1, general_interlaced_source_flag equal to 0, general_non_packed_constraint_flag equal to 1, and general_frame_only_constraint_flag equal to 1.

If stereoscopic 3D video is supported, ITU-T Recommendation H.264 / MPEG-4 (Part 10) AVC [52] Stereo High Profile (SHP) Level 3.1 with frame_mbs_only_flag=1 should be supported. When an H.264 (AVC) SHP sub-bitstream containing the base view only complies with Level 1.3 or below, it should be constrained as follows: the value of the profile_idc should be equal to 66 and the value of the constraint_set1_flag should be equal to 1 in all active sequence parameter sets, i.e. the H.264 (AVC) Constrained Baseline Profile should be indicated to be used for the base view. There are no requirements on output timing conformance of H.264 (AVC) decoding (Annex C of [52]) or H.265 (HEVC) decoding (Annex C of [62]).

If 2D vector graphics is supported, Scalable Vector Graphics (SVG) Tiny 1.2 [20][21] and ECMAScript [55] shall be supported.

To ensure interoperability for the transport of video and associated speech/audio and timed text in an MM, the 3GPP file format with Basic profile shall be supported. The usage of the 3GPP file format shall follow the technical specifications and the implementation guidelines specified in TS 26.233

MMS clients and servers that support HTML shall support the 3GPP HTML5 profile as defined in [63]. MMS servers should support translation from other scene description formats, such as SMIL [24] and XHTML Mobile Profile [30] to HTML5. The MMS client that supports HTML shall include the HTML5 MIME type "text/html" as part of the User Agent header field in the request sent to the server. The MMS Relay/Server shall not accept an MMS message using HTML5 presentation unless it supports HTML5 presentation format and supports transcoding to SMIL 2.0 or XHTML Mobile Profile. For this purpose, the MMS Relay/Server uses the capability negotiation as defined in section 7.1.3.1 of [22] to detect the user agent's capabilities. All referenced resources should be delivered as part of the same multi-part MIME document, where the HTML5 document shall be the root part. The 3GPP MMS uses a subset of SMIL 2.0 [24] for media synchronization and scene description. MMS clients and servers with support for media synchronization and scene descriptions shall support the 3GPP SMIL Language Profile defined in [34]. This profile is a subset of the SMIL 2.0 Language Profile but a superset of the SMIL 2.0 Basic Language Profile. Document [34] also includes an informative annex A that provides guidelines for SMIL content authors. Additionally, XHTML Mobile Profile [30] for scene description should be supported. MMS clients and servers with support for scene descriptions based on XHTML shall support XHTML Mobile Profile [30], defined by the WAP Forum. XHTML Mobile Profile is a subset of XHTML 1.1 but a superset of XHTML Basic.

If timed text is supported, MMS clients shall support [35] with 3GP files using Basic profile [33].

If Rights Management is supported, OMA Digital Rights Management (DRM) 1.0 [56] [57] [58] shall be supported.

If Personal Data Interchange is supported this shall be done according to the OMA vObject Minimum Interoperability Profile [59].

If dynamic and interactive multimedia scene is supported, MMS clients and servers shall support TS 26.142.