1、Rec. ITU-R BT.1377 1RECOMMENDATION ITU-R BT.1377*LABELLING OF VIDEO AND AUDIO APPARATUSTHROUGHPUT (PROCESSING) DELAY(Question ITU-R 35/11)(1998)Rec. ITU-R BT.1377The ITU Radiocommunication Assembly,consideringa) that the delay through digital audio and/or video equipment may be significant;b) that e
2、quipment processing delay may affect sound/vision timing;c) that throughput delay may be large especially with Video Codecs;d) that the processing time through a piece of equipment might not be readily apparent to the user;e) that for some items of equipment the processing delay times are known to m
3、anufacturers;f) that the marking of equipment processing delay time would assist in the identification and correction ofpotential system timing problems,recommends1 in cases where the processing delay times are known to the manufactures, it is desirable that throughput delaysbe clearly identified on
4、 digital audio and video equipment,further recommends2 that such delays be indicated for the normal operating state and expressed in milliseconds as a value or rangeof values where the delay is variable;3 in case of equipment such as frame synchronizers, it is desirable to indicate the delay in real time by a signalappropriate for controlling a companion audio delay._*This Recommendation should be brought to the attention of the International Electrotechnical Commission (IEC) and toRadiocommunication Study Group 10.
