1、 Rec. ITU-R BS.1423 1 RECOMMENDATION ITU-R BS.1423 GUIDELINES FOR PRODUCING MULTICHANNEL SOUNDTRACKS USING SURROUND MATRIX TECHNIQUES (Question ITU-R 211/10) (1999) Rec. ITU-R BS.1423 The ITU Radiocommunication Assembly, considering a) that a large and growing number of 35 mm feature films are produ
2、ced in multichannel sound; b) that the Dolby Surround format was launched to allow the multichannel sound accompaniment from the cinema environment to be conveyed over two-channel delivery media; c) that the Dolby Surround format has spread widely and today is available in many households; d) that a
3、 large number of broadcasters are transmitting or planning to transmit these films employing the Dolby Surround system to television viewers; e) that a large number of home television viewers are equipped to reproduce matrix surround encoded soundtracks in their homes; f) that a large majority of th
4、ose television viewers use the Dolby Pro Logic surround decoder; g) that broadcasters may produce and deliver multichannel programmes employing the same Dolby Surround format that is used with feature films; h) that a larger existing base of viewers are still equipped with mono and stereo reproducti
5、on equipment, which will be receiving multichannel sound; j) that new multichannel sound transmissions must be compatible with existing mono and stereo equipment; k) that production of multichannel sound requires correct technological procedures before transmission in order to assure compatibility w
6、ith monophonic, stereophonic, and surround sound reproduction, recommends 1 that during matrix surround programme mixing, the resulting sound image should be checked by monitoring the signal after it has undergone the matrix surround encoding/decoding process; 2 that during mixing, the stereo and mo
7、no compatibility of the resulting signal be checked; 3 that an active matrix surround sound decoder with characteristics of those used in the majority of consumer homes should be used for monitoring; 4 that the programme material produced in this manner should be clearly labelled as being matrix sur
8、round encoded so that operational personnel will be aware of the signal format (see Note 1); 5 that the primary multi-track source material (8 to 48 tracks, if available) used before the matrix encoding should be preserved (see Note 2). This will allow a discrete 5-channel down-mix to be produced fo
9、r use with a future multichannel sound broadcast system. NOTE 1 Programme providers may wish to label the programme as being matrix surround encoded within the programme content so that the audience can be aware of the signal format. With prior arrangement (see http:/), programmes may be labelled with the Dolby Surround logo. NOTE 2 Recommendation ITU-R BR.1384 contains specifications on recording track assignments for multichannel programmes.