Background and justification

Media coding is a key element of multimedia communications and encompasses several areas for study:

• still-image coding;
• character coding;
• graphic coding;
• computer data compression;
• moving image coding;
• audio coding (20-20 000 Hz);
• wideband coding (50-7 000 Hz);
• narrow-band (or telephony band) coding (200-3 400 Hz).

This question will address the media coding topics that affect conversational and non-conversational applications, such as conventional and IP telephony, audiovisual multimedia communications, that have not been addressed by other media coding questions in ITU-T. This Question will also address the need to define extensions to existing ITU-T media coding Recommendations for use in conversational and non-conversational services and systems.

Study items

• Extension of existing Recommendations when the work cannot be meaningfully addressed in current ITU-T media coding Questions including:
• coding of moving image;
• audio coding;
• wideband and narrow-band signal coding, including scalability issues, pre- and post-processing functions, including discontinuous transmission and comfort noise generation algorithms, noise suppression techniques, packet loss concealment methods;
• embedded and layered coding of speech, in particular for packet-based (including IP) and wireless applications;
• computer data compression.
• Harmonization of media coding activities with other standard development organizations (SDOs).
• Packetization definition issues.
• Security aspects that directly affect media coding including watermarking techniques.

Specific tasks

This question will deal with the study items as contributions are made available to determine whether:

• the work should be allocated to an existing question; or
• for studies that require a short-term effort, an ad hoc group should be created with a specific mandate; or
• for studies that require a medium- or long-term effort, to propose to the study group the establishment of a new question or the revision of an existing one.

Relationship

• Other relevant Questions of Study Group 16.
• ITU-T Study Group 8 on still-image coding.
• ITU-T SG 11 and ITU-R SG 8 on IMT-2000 issues.
• ITU-T Study Group 12 on end-to-end performance issues.
• ITU-T Study Group 13: IP, ATM, ISDN and general network issues.
• ITU-T Study Group 15: on network signal processing issues, including echo cancellers and digital circuit multiplication equipment.
• IETF for media packetization issues.
• 3GPP, 3GPP-2 and WAP Forum for wireless applications.
• ISO/IEC JTC 1/SC 29 (MPEG, JPEG) for still- and motion image and audio coding.
• ISO/IEC JTC 1/SC 2 for character coding.
• W3C for HTML.