Challenging 5 Common Assumptions about Videoconferencing Milton Chen Computer Systems Lab Stanford University Presented at Internet2 Advanced Applications.

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<ul><li><p>Challenging 5 Common Assumptions about VideoconferencingMilton ChenComputer Systems LabStanford University</p><p>Presented at Internet2 Advanced Applications Track 10/28/2002 </p><p>Copyright 2002 Milton Chen</p></li><li><p>The Stanford Video Auditoriumdesktop interface15 x 5 video wall</p><p>Copyright 2002 Milton Chen</p></li><li><p>Video Auditorium publicity/usersIntel president Paul Otellinis Intel Developer Forum keynoteInvited demo to NASA headquarters for Paul G. Pastorek</p><p>CANARIE, CanadaCUDI, MexicoComdex, BrazilIBM Almaden LabManhattan College Hopkins Marine Station Stanford Medical SchoolStanford Learning LabStanford Center for Design ResearchBerkeley Bioengineering LabUniversidade Federal do Rio Grande do Sul, Brazil</p><p>Copyright 2002 Milton Chen</p></li><li><p>OutlineCommon assumptionsTechnology1. High-fidelity AV requires dedicated hardware2. Difficult to install and useHuman factors3. Life size displays are ideal4. Floor control requires interactive frame rate5. Eye contact is difficultBeyond MCU and H323Peer-to-peerStanfords Port Bootstrap ProtocolPersonal directoryAn evaluation of distance learning at StanfordWhy videoconferencing is not ubiquitous</p></li><li><p>1. High-fidelity low-latency AV requires dedicated hardware</p><p>Copyright 2002 Milton Chen</p></li><li><p>Your PC outperforms all dedicated systems$700 Pentium 4 computer$7000 systemsoutperforms</p><p>Copyright 2002 Milton Chen</p></li><li><p>Comparison of videoconferencing solutions* CUSeeME, iVisit, Yahoo messenger have unacceptable latency</p><p>Max number of linksMax video resolutionBW required at 352x288 15fpsNetMeeting1352x288200 KbpsWIDE DVTS1720x4803000 KbpsVbrick1720x4802000 KbpsPolycom, Sony, 4 352x288200 KbpsAccessGrid, VRVSmany720x480400 KbpsStanford Video Auditorium16 to more than 100720x480100 Kbps</p><p>Copyright 2002 Milton Chen</p></li><li><p>demo</p><p>Copyright 2002 Milton Chen</p></li><li><p>A scalable AV streaming architecture* TrueSpeech 8.5* MPEG-4* Encrypted, AES (Rijndael), streaming* Simultaneous AV recording* Perceptual streaming adapts to network conditions</p><p>audio captureaudio compressaudio sendaudio receiveaudio decompressaudio rendervideo capturevideo compressvideo sendvideo receivevideo decompressvideo render*</p><p>Copyright 2002 Milton Chen</p></li><li><p>Beyond MCU and H323MCU vs. peer-to-peerScalabilityEase of deployment</p><p>H323 vs. Stanfords Port-Bootstrap ProtocolFirewallEase of deployment</p><p>Personal directory</p><p>Copyright 2002 Milton Chen</p></li><li><p>2. Videoconferencing systems are difficult to install and use</p><p>Copyright 2002 Milton Chen</p></li><li><p>One click operationTo use the Video Auditorium Nothing to installOne click on the html speed dial</p><p>Makes conferencing as simple as surfing the web</p><p>Copyright 2002 Milton Chen</p></li><li><p>3. Life size displays are ideal</p><p>Copyright 2002 Milton Chen</p></li><li><p>Each video should be between 6 and 14 wide* 12 people sat 10 from the display Subjectively, people reported 6 as minimum and 14 as ideal. Life size is 12.</p><p>Copyright 2002 Milton Chen</p><p>Chart2</p><p>312.523.28733561423.287335614</p><p>314.857142857131.077476149331.0774761493</p><p>339.220.837466256720.8374662567</p><p>413.428571428669.298526061469.2985260614</p><p>525.7142857143104.3387340759104.3387340759</p><p>video size (deg of visual angle)</p><p>time (msec)</p><p>smile recognition time</p><p>out</p><p>claire1370364542636</p><p>charles2280279311311355</p><p>kimmie3327314333389579</p><p>keis4330333333423574</p><p>susan5332320386405</p><p>ada6286283432589</p><p>yh7320305355411542</p><p>dan8</p><p>danny9</p><p>amol10</p><p>11</p><p>12</p><p>avg312.5314.8571428571339.2413.4285714286525.7142857143</p><p>stdev23.28733561431.077476149320.837466256769.2985260614104.3387340759</p><p>angle (degree)26.9616.848.354.182.03</p><p>width (pixel)102464032016080</p><p>plus335.787335614345.9346190064360.0374662567482.72709749630.0530197902</p><p>minus289.212664386283.7796667079318.3625337433344.1300453671421.3755516383</p><p>T test0.03716222870.05437863390.0023275860.0022268581</p><p>angle (degree)26.9599837916.836516438.3451036624.1780857772.030042598</p><p>avg312.5314.8571428571339.2413.4285714286525.7142857143</p><p>out</p><p>23.28733561423.287335614</p><p>31.077476149331.0774761493</p><p>20.837466256720.8374662567</p><p>69.298526061469.2985260614</p><p>104.3387340759104.3387340759</p><p>field of view (deg)</p><p>recognition time (ms)</p><p>23.28733561423.287335614</p><p>31.077476149331.0774761493</p><p>20.837466256720.8374662567</p><p>69.298526061469.2985260614</p><p>104.3387340759104.3387340759</p><p>video size (deg of visual angle)</p><p>time (msec)</p><p>smile recognition time</p></li><li><p>Balance between size and head movements* 12 people viewed 9 and 36 students on a large and immersive display. Immersive display requires head movements to see all the students.91474</p><p>Copyright 2002 Milton Chen</p><p>Chart2</p><p>0.750.25</p><p>0.16666666670.8333333333</p><p>large (27)</p><p>immersive (64)</p><p>class size</p><p>preference</p><p>Sheet1</p><p>9 stu36 stu</p><p>claire111</p><p>charles211</p><p>kimmie313</p><p>keis413</p><p>susan513</p><p>ada633</p><p>yh713</p><p>dan813</p><p>danny933</p><p>amol1033</p><p>karen1113</p><p>francois1213</p><p>largeimmersive</p><p>9 students9312</p><p>36 students21012</p><p>large (27)immersive (64)</p><p>9 students0.750.25</p><p>36 students0.16666666670.8333333333</p><p>Sheet1</p><p>36 stu</p><p>9 stu</p><p>subject</p><p>number of displays</p><p>Sheet2</p><p>large (27)</p><p>immersive (64)</p><p>class size</p><p>preference</p><p>Sheet3</p></li><li><p>4. Effective floor control requires interactive frame rate</p><p>Copyright 2002 Milton Chen</p></li><li><p>Minimum required frame rateInteractive 10 fps</p><p>Tolerable5 fps[Tang and Isaac 93]Lip synchronization5 fps[Watson and Sasse 96]Content understanding 5 fps[Ghinea and Thomas 98]Sign language recognition 1 fps[Johnson and Caird 96]</p><p>Copyright 2002 Milton Chen</p></li><li><p>Gesture Detection Algorithminput imageframe differenceafter erosionVisualization of algorithm</p><p>Copyright 2002 Milton Chen</p></li><li><p>Requires 10% of full motion bandwidthfull-motion (10 fps)gesture-sensitive (0.2 fps)* MPEG4 encoded at 320x240</p><p>Copyright 2002 Milton Chen</p><p>Chart1</p><p>15.776</p><p>6.376</p><p>7.984</p><p>7.064</p><p>8.544</p><p>0.52</p><p>6.728</p><p>0.552</p><p>5.384</p><p>0.536</p><p>4.52</p><p>0.432</p><p>3.64</p><p>0.48</p><p>3.864</p><p>13.752</p><p>0</p><p>5.072</p><p>0.432</p><p>5.896</p><p>5.528</p><p>6.848</p><p>6.96</p><p>8.584</p><p>6.512</p><p>9.52</p><p>9.816</p><p>11.4</p><p>10.976</p><p>7.968</p><p>19.624</p><p>9.088</p><p>7.392</p><p>13.472</p><p>13.648</p><p>8.624</p><p>11.976</p><p>8.864</p><p>15.104</p><p>8.368</p><p>13.344</p><p>7.376</p><p>13.848</p><p>3.648</p><p>8.544</p><p>15.824</p><p>4.336</p><p>10.512</p><p>7.76</p><p>9.872</p><p>8.536</p><p>9.496</p><p>7.272</p><p>8.896</p><p>7.224</p><p>9.576</p><p>7</p><p>11.072</p><p>9.288</p><p>9.912</p><p>15.384</p><p>2.144</p><p>8.208</p><p>7.056</p><p>8.56</p><p>7.744</p><p>7.928</p><p>10.472</p><p>14.088</p><p>7.912</p><p>14.544</p><p>9.048</p><p>15.208</p><p>5.248</p><p>12.024</p><p>7.352</p><p>12.496</p><p>11.024</p><p>5.944</p><p>12.136</p><p>5</p><p>10.152</p><p>7.504</p><p>8.408</p><p>7.768</p><p>77.624</p><p>8.072</p><p>8.664</p><p>7.856</p><p>8.816</p><p>19.136</p><p>3.32</p><p>9.352</p><p>7.36</p><p>8.032</p><p>7.168</p><p>7.92</p><p>0.52</p><p>8.424</p><p>7.072</p><p>7.472</p><p>0.6</p><p>7.96</p><p>6.12</p><p>7.176</p><p>15.88</p><p>5.984</p><p>7.128</p><p>6.344</p><p>6.52</p><p>7.176</p><p>8</p><p>6.92</p><p>8.504</p><p>6.568</p><p>7.056</p><p>0.528</p><p>7.2</p><p>0.528</p><p>5.848</p><p>13.616</p><p>5.04</p><p>6.248</p><p>5.472</p><p>6.432</p><p>4.784</p><p>4.856</p><p>5.32</p><p>6.488</p><p>5.28</p><p>5.736</p><p>4.824</p><p>5.264</p><p>0.472</p><p>4.768</p><p>13.664</p><p>1.968</p><p>6.744</p><p>0.536</p><p>8.104</p><p>0.584</p><p>7.432</p><p>5.96</p><p>6.488</p><p>0.512</p><p>5.736</p><p>0.552</p><p>5.736</p><p>0.456</p><p>3.92</p><p>12.64</p><p>0</p><p>5.072</p><p>0.48</p><p>3.648</p><p>0.44</p><p>3.912</p><p>0.464</p><p>3.672</p><p>0.432</p><p>4.12</p><p>0.488</p><p>3.76</p><p>0.392</p><p>3.656</p><p>12.08</p><p>0.32</p><p>4.84</p><p>0.488</p><p>3.904</p><p>4.072</p><p>5.4</p><p>5</p><p>6.488</p><p>0.504</p><p>4.832</p><p>5.064</p><p>6.36</p><p>0.568</p><p>6.736</p><p>13.032</p><p>0.744</p><p>6.36</p><p>5.424</p><p>5.952</p><p>75.328</p><p>4.8</p><p>0.504</p><p>5.952</p><p>4.6</p><p>4.696</p><p>0.472</p><p>3.68</p><p>0.4</p><p>4.432</p><p>16.072</p><p>0</p><p>5.976</p><p>5.248</p><p>6</p><p>0.472</p><p>4.432</p><p>0.408</p><p>4.248</p><p>0.416</p><p>4.328</p><p>0.4</p><p>4.648</p><p>0.44</p><p>4.192</p><p>13.768</p><p>0</p><p>6.784</p><p>5.84</p><p>5.536</p><p>0.536</p><p>5.416</p><p>0.424</p><p>5.36</p><p>4.712</p><p>4.72</p><p>0.44</p><p>5.304</p><p>0.576</p><p>5.504</p><p>14.632</p><p>6.76</p><p>8.864</p><p>10.032</p><p>9.656</p><p>10.72</p><p>11.808</p><p>7.736</p><p>16.752</p><p>12.776</p><p>12.592</p><p>9.008</p><p>9.92</p><p>7.944</p><p>10.232</p><p>6.144</p><p>14.992</p><p>4.704</p><p>6.304</p><p>9.224</p><p>6.928</p><p>7.8</p><p>5.512</p><p>9.352</p><p>7.616</p><p>7.944</p><p>9.656</p><p>12.696</p><p>10.976</p><p>10.496</p><p>15.768</p><p>9.872</p><p>6.264</p><p>14.488</p><p>7.144</p><p>7.16</p><p>17.264</p><p>2.736</p><p>9.392</p><p>7.792</p><p>6.992</p><p>5.712</p><p>7.328</p><p>6.424</p><p>7.424</p><p>15.136</p><p>3.264</p><p>9.392</p><p>7.2</p><p>7.856</p><p>6.744</p><p>7.504</p><p>0.52</p><p>5.992</p><p>0.544</p><p>5.28</p><p>0.488</p><p>4.424</p><p>0.456</p><p>3.84</p><p>72.864</p><p>0.328</p><p>6.112</p><p>0.424</p><p>4.552</p><p>0.4</p><p>4.04</p><p>0.424</p><p>3.76</p><p>0.432</p><p>3.704</p><p>0.448</p><p>3.448</p><p>0.488</p><p>3.592</p><p>time (frame number)</p><p>frame size (kbits)</p><p>ViSend_time</p><p>full motionlow updategesture sensitivefull motiongesture sensitivelow updatefullgesturelow</p><p>019336933693360197200015.77600</p><p>10410017970016.37600</p><p>207810029980027.98400</p><p>30540038830037.06400</p><p>4052600410680048.54400</p><p>5055005650050.5200</p><p>604950068410066.72800</p><p>7048007690070.55200</p><p>805030086730085.38400</p><p>9056009670090.53600</p><p>100539001056500104.5200</p><p>11058000115400110.43200</p><p>120746001245500123.6400</p><p>1306300136000130.4800</p><p>140900001448300143.86400</p><p>150197200151719001513.75200</p><p>160797001600016000</p><p>170998001763400175.07200</p><p>18088300185400180.43200</p><p>1901068001973700195.89600</p><p>20065002069100205.52800</p><p>210841002185600216.84800</p><p>22069002287000226.9600</p><p>2306730023107300238.58400</p><p>24067002481400246.51200</p><p>2505650025119000259.5200</p><p>260540026122700269.81600</p><p>27045500271425002711.400</p><p>2806000281372002810.97600</p><p>290483002999600297.96800</p><p>300171900302453003019.62400</p><p>31000031113600319.08800</p><p>320634003292400327.39200</p><p>3305400331684003313.47200</p><p>34073700341706003413.64800</p><p>3506910035107800358.62400</p><p>36085600361497003611.97600</p><p>3708700037110800378.86400</p><p>380107300381888003815.10400</p><p>3908140039104600398.36800</p><p>400119000401668004013.34400</p><p>4101227004192200417.37600</p><p>420142500421731004213.84800</p><p>4301372004345600433.64800</p><p>4409960044106800448.54400</p><p>450245300451978004515.82400</p><p>4601136004654200464.33600</p><p>47092400471314004710.51200</p><p>4801684004897000487.7600</p><p>49017060049123400499.87200</p><p>50010780050106700508.53600</p><p>51014970051118700519.49600</p><p>5201108005290900527.27200</p><p>53018880053111200538.89600</p><p>5401046005490300547.22400</p><p>55016680055119700559.57600</p><p>56092200568750056700</p><p>570173100571384005711.07200</p><p>5804560058116100589.28800</p><p>59010680059123900599.91200</p><p>600197800601923123912396015.3849.9129.912</p><p>610542006126800612.14400</p><p>62013140062102600628.20800</p><p>630970006388200637.05600</p><p>64012340064107000648.5600</p><p>6501067006596800657.74400</p><p>6601187006699100667.92800</p><p>67090900671309006710.47200</p><p>680111200681761006814.08800</p><p>690903006998900697.91200</p><p>700119700701818007014.54400</p><p>7108750071113100719.04800</p><p>720138400721901007215.20800</p><p>7301161007365600735.24800</p><p>740123900741503007412.02400</p><p>7501923192319237591900757.35200</p><p>76026800761562007612.49600</p><p>770102600771378007711.02400</p><p>780882007874300785.94400</p><p>790107000791517007912.13600</p><p>80096800806250080500</p><p>81099100811269008110.15200</p><p>8201309008293800827.50400</p><p>83017610083105100838.40800</p><p>840989008497100847.76800</p><p>850181800859703008577.62400</p><p>86011310086100900868.07200</p><p>87019010087108300878.66400</p><p>880656008898200887.85600</p><p>89015030089110200898.81600</p><p>90091900902392009019.13600</p><p>9101562009141500913.3200</p><p>92013780092116900929.35200</p><p>930743009392000937.3600</p><p>94015170094100400948.03200</p><p>950625009589600957.16800</p><p>9601269009699000967.9200</p><p>97093800976500970.5200</p><p>98010510098105300988.42400</p><p>990971009988400997.07200</p><p>1001970300100934001007.47200</p><p>101010090010175001010.600</p><p>1020108300102995001027.9600</p><p>103098200103765001036.1200</p><p>1040110200104897001047.17600</p><p>105023920010519850010515.8800</p><p>106041500106748001065.98400</p><p>1070116900107891001077.12800</p><p>108092000108793001086.34400</p><p>1090100400109815001096.5200</p><p>110089600110897001107.17600</p><p>111099000111100000111800</p><p>11206500112865001126.9200</p><p>11301053001131063001138.50400</p><p>114088400114821001146.56800</p><p>115093400115882001157.05600</p><p>1160750011666001160.52800</p><p>117099500117900001177.200</p><p>11807650011866001180.52800</p><p>119089700119731001195.84800</p><p>120019850012017020012013.61600</p><p>121074800121630001215.0400</p><p>122089100122781001226.24800</p><p>123079300123684001235.47200</p><p>124081500124804001246.43200</p><p>125089700125598001254.78400</p><p>1260100000126607001264.85600</p><p>127086500127665001275.3200</p><p>1280106300128811001286.48800</p><p>129082100129660001295.2800</p><p>130088200130717001305.73600</p><p>13106600131603001314.82400</p><p>132090000132658001325.26400</p><p>1330660013359001330.47200</p><p>134073100134596001344.76800</p><p>135017020013517081708170813513.66413.66413.664</p><p>136063000136246001361.96800</p><p>137078100137843001376.74400</p><p>13806840013867001380.53600</p><p>1390804001391013001398.10400</p><p>14005980014073001400.58400</p><p>141060700141929001417.43200</p><p>142066500142745001425.9600</p><p>143081100143811001436.48800</p><p>14406600014464001440.51200</p><p>145071700145717001455.73600</p><p>14606030014669001460.55200</p><p>147065800147717001475.73600</p><p>1480590014857001480.45600</p><p>149059600149490001493.9200</p><p>150017081708170815015800015012.6400</p><p>151024600151000151000</p><p>152084300152634001525.07200<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