MC同步容限与内容有关 ◆人对于视频/音频之间同步程度的感知与视频内容有 关 (a) (b) (c) Fig.1.(a)Head view;(b)shoulder view;(c)body view. http://www.kom.tu-darmstadt.de/en/people/staff/ralf-steinmetz/ Human Perception of Jitter and Media Synchronization IEEE JOURNAL on Selected Areas on Communications,Vol.14,No.1,Jan 1996 Google Scholars显示引用550次(2016.11)
{ynh,cxh}@ustc.edu.cn 同步容限与内容有关 人对于视频/音频之间同步程度的感知与视频内容有 关 16 Human Perception of Jitter and Media Synchronization IEEE JOURNAL on Selected Areas on Communications, Vol. 14, No. 1, Jan 1996 Google Scholar显示引用550次(2016.11) http://www.kom.tu-darmstadt.de/en/people/staff/ralf-steinmetz/
Level Of Annoyance [ 100 80 Level of Annoyance 60 40 20 Level Of Annoyance[%] 100 320-280-240-200-160-120-80-4004080120160200240280320 80 ennoying indi㎡erent器acceptable Skew fmsec] View:Head 60 Fig.17.Level of Annoyance at head view-Left part:negative skew,video ahead of audio;right part:positive skew,video behind audio. 40 20 Level Of Annoyance [ 100 320-280-240-200-160-120-80-4004080120160200240280320 80 annoying藏indifte制ert徽acceptable Skew [msec] View:Body 60 Fig.19.Level of Annoyance at body view-Left part:negative skew,video ahead of audio;right part:positive skew,video behind audio. 40 20 320-280-240200-160-120-89-4004080120160209240280320 annoying 酶Indiferent.cceptabie S张ew[msec View:Shoulder Fig.18.Level of Annoyance at shoulder view-Left part:negative skew, 17 ynh.cxh @ustc.edu.cn video ahead of audio:right part:positive skew,video behind audio
{ynh,cxh}@ustc.edu.cn Level of Annoyance 17
Correctly Detected Errors[] 100 80 Correctly Detected Error 60 40 Correctly Detected Errors[] 20 100 80 320-280-240-200-160-12080-4004080120160200240280320 Skew [msec] 腾correct器ont know额Inoored 60 View:Head Fig.14.Correct detection of synchronization errors at head view-Left part: 40 negative skew,video ahead of audio;right part:positive skew,video behind audio. Correctly Detected Errors [ 20 100数 320-280-240-200-160-12080-40·04080120160200240280320 80 somect整don't know■ Incorreet Skew fmsec间 View:Body 60 Fig.16..Correct detection of synchronization errors at body view--Left part: 40 negative skew,video ahead of audio;right part:positive skew,video behind audio. 20 320-280-240-200-160-120-80-4004080120160200240280320 徽correct Skew fmsec] don't know incorrect View:Shoulder Fig.15.Correct detection of synchronization errors at shoulder view-Left part:negative skew,video ahead of audio;right part:positive skew,video 18 ynh.cxh @ustc.edu.cn behind audio
{ynh,cxh}@ustc.edu.cn Correctly Detected Error 18
TABLE I QUALITY OF SERVICE FOR SYNCHRONIZATION PURPOSES 958 Media Mode,Application QoS video animation correlated +/-120ms audio lip synchronization +/-80ms image overlay +/-240n5 non overlay +/-500ms text overlay +-240ms non overlay +/-500ms audio animation event correlation (e.g.dancing) +/-80ms andio tightly coupled(stereo) +人11s loosely coupled (dialog mode with'var- +/120ms ious participants) loosely coupled (e.g.background +/500ms music) image tightly coupled (e.g.music with notes) +/-5ms loosely coupled (e.g.slide show) +/-500ms text text annotation +/240ms pointer audio relates to showed item -500ms, +750ms2 cxh@ustc.edu.cn 一中
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MC RECOMMENDATION ITU-R BT.1359 [1998] Relative timing of sound and vision for broadcasting Detectability and acceptability thresholds Undetectability plateau 0 (ape13J! Detectability threshold B B -0.5 siInsal uonen[eAa A Acceptability threshold A -1.5 Sound delay wrt Sound advanced wrt vision vision L上⊥⊥⊥⊥上L⊥⊥⊥⊥上⊥⊥L⊥⊥⊥ 2 -200-180-160-140-120-100-80-60-40-20 0 20 40 60 80 100 Delay time(ms) skew should be kept within +22.5 ms and -30 ms positive skew:video behind audio ynh,cxh@ustc.edu.cn
{ynh,cxh}@ustc.edu.cn RECOMMENDATION ITU-R BT.1359 [1998] Relative timing of sound and vision for broadcasting Detectability and acceptability thresholds 22 skew should be kept within +22.5 ms and -30 ms positive skew: video behind audio