14:02:26 RRSAgent has joined #webtv 14:02:26 logging to http://www.w3.org/2017/06/28-webtv-irc 14:03:32 meeting: Media and Entertainment IG - Cloud Browser TF 14:03:40 present+ Alexandra, Colin, Kaz 14:03:50 alex has joined #webtv 14:03:56 hello 14:05:06 alex: during the previous call 14:05:16 ... we had a brief chat on the IG Note 14:05:28 ... we can start over with the use cases 14:05:46 ... have 2 points 14:06:14 colin: updating the wiki page 14:06:36 alex: quality of experience/service 14:06:56 ... also MSE stuff 14:07:32 alex: let's go through the use case wiki 14:07:54 colin: not in a formal description yet 14:08:10 ... starting with "UI scale" 14:08:36 ... resolution like a scroll bar 14:08:59 ... could be scaled down in a cloud browser 14:09:16 q+ 14:09:28 ... what is different with the cloud browser solution? 14:09:46 ... that is the first use case 14:10:08 alex: in your view, what would be the impact for APIs 14:10:17 s/APIs/APIs?/ 14:10:38 colin: you could look up device pixel ratio, etc. 14:10:49 ... and user resolution 14:11:09 ... prefer using guidelines for this 14:11:19 q? 14:12:09 kaz: possible collaboration between a cloud browser and another screen like a smartphone? 14:12:58 ... possibly included in "displayed in another way (e.g. in a PiP)" 14:13:35 colin: yes, but Cloud Browser doesn't know how to send that information (at the moment) 14:14:19 kaz: maybe we need another channel or connection for that purpose 14:14:23 coline: yeah 14:14:46 ... so would see existing guidelines for that kind of requirements 14:15:33 alex: possible control channel between the cloud browser and the server 14:16:10 ... but we also would see guidelines because this need is not the first one 14:16:54 colin: cloud browser and abstract orchestration layer 14:17:10 ... two different levels 14:18:36 ... same for the devicePixelRatio as well 14:19:43 alex: we can decide use cases and requirements first 14:19:59 ... and then think about what kind of APIs are needed 14:21:09 colin: ok 14:21:12 ... let's move ahead 14:21:26 ... "UI visibility timing" 14:21:46 i/UI/topic: UI visibility timing/ 14:22:12 colin: when does the end user sees the UI screen? 14:22:22 alex: interesting 14:22:49 i/interesting/Since the UI is terminated in the cloud it is hard to tell when the user actually sees it. 14:22:58 topic: Media capabilities 14:23:36 kaz: fine 14:24:12 ... but maybe we should call these topics as "difficulties" or "issues" as the starting point of concrete/detailed use case descriptions 14:24:49 colin: ok 14:24:54 ... (move ahead) 14:25:38 ... n a cloud browser solution you would also like to know which types are played natively on the client device and which are transcoded. 14:25:44 s/n a/on a/ 14:25:56 ... some examples of codec 14:26:17 [[ 14:26:18 var support = videoElement.canPlayType('type=\'video/mp4; codecs="avc1.42E01E, mp4a.40.2"\); if (support == "probably") console.log("natively supported") else if (support == "virtually") console.log("supported by transcoding") 14:26:19 ]] 14:26:46 colin: existing APIs could be extended for cloud browser 14:27:22 topic: Identification 14:27:43 colin: identification is also a problem with cloud browser 14:27:53 ... for example, with geolocation api 14:28:11 Chris has joined #webtv 14:28:29 ... how to identify the cloud browser and its device? 14:29:13 ... also we need a means to analyze the problems 14:29:51 q+ 14:31:44 alex: we need to clarify our requirements and also existing APIs (=gap analysis) 14:32:02 colin: and the WG side should make decision about concrete APIs 14:32:14 present+ Chris 14:32:42 colin: will update these description to generate proper use cases 14:33:01 (chris joins) 14:33:07 chris: will check the minutes 14:33:18 ... any concrete expectation from me? 14:34:08 colin: now we're talking about Quality of Service/Experiece 14:34:14 s|Experiece|Experience| 14:34:28 kaz: "Quality" could include accessibility. right? 14:34:44 colin: right. but we have another separate section for accessibility 14:35:01 chris: what is the difference between QoE and accessibility? 14:36:39 kaz: maybe we could ask Chris to review all the use cases including QoS/QoE, couldn't we? 14:37:25 coling: indeed related to each other 14:37:36 chris: accessibility/usability viewpoint 14:38:08 s/coling/colin/ 14:38:29 colin: "usability" has some specific meaning for broadcasting 14:39:01 alex: there is another viewpoint from telecommunication as well 14:39:11 ... QoS may include latency issue 14:39:31 q? 14:39:40 alex: another question is 14:40:21 ... have you thought about latency and packet loss? 14:40:51 colin: have not done yet 14:41:29 alex: ITU recommendation on video quality and how to measure it 14:42:51 ... also what is important for each user? 14:43:09 ... big issue with operation 14:44:08 ... big infrastructure for QoS 14:44:35 ... the operator sees problems on what QoS is 14:44:54 colin: need to clarify what is expected for cloud browser UI 14:45:52 ... would highlight generic problems within this group 14:45:57 q? 14:46:02 ack k 14:47:09 kaz: possible intermediate proxy server for identification topic? 14:47:22 colin: have wide channel use case 14:47:57 ... you need to add some information if you have multiple cloud browser devices at the same geolocation 14:49:29 kaz: a possible use case is a collaborative game by multiple users at some specific meeting room 14:50:11 colin: need a mechanism of communication with each other for multi-user game 14:50:39 alex: broadcasting vs unicasting 14:51:00 colin: we should clarify delivery mechanism for each specific use case 14:52:10 topic: MSE issues 14:52:25 alex: we have problems with MSE for Cloud Browser 14:53:15 ... how we could adapt MSE for Cloud Browser? 14:53:21 -> https://www.w3.org/2011/webtv/wiki/Main_Page/Cloud_Browser_TF/UseCases/MSE MSE use cases 14:53:50 -> https://www.w3.org/2011/webtv/wiki/Main_Page/Cloud_Browser_TF/UseCases/MSE#UC-3_Cloud-based_MSE_support UC3 Cloud-based MSE support 14:54:02 alex: explains the use case 14:54:51 ... MSE is complex. Cloud Browser is also complex 14:55:02 ... the mixture of them would be more complex 14:55:24 ... we have a lot of steps within this UC 14:56:01 ... split into 4 sub use cases 14:56:15 ... 3.1 Execution of XHR 14:57:22 [[ 14:57:23 CB initiates a session with the CB client (session id, user id) 14:57:23 The CB client requests a web application that uses MSE for video delivery 14:57:23 CB executes the web application: CB parses the html and css data, web app sets the HTMLMediaElement 14:57:23 The web application requests the manifest (mpd, etc.) file and the CB parses it 14:57:24 The web application creates mediaSource objects and associates it with HTMLMediaElement 14:57:25 mediaSource creates sourceBuffer objects that in turn append media segments into the SourceBuffer array with the appenBuffer method 14:57:28 The web application defines the media segment URLs (with byte range params, video chunks id, etc.) 14:57:30 The web application sends the XMLHTTP Requests towards the media host to request these media segment 14:57:32 As the media segments are downloaded by the client, these XMLHTTP Requests are forwarded to the CB client by the CB. 14:57:35 ]] 14:57:59 alex: cloud browser doesn't know what request is being executed 14:58:53 [[ 14:58:58 Gap1: in MSE the Web browser currently does not have any metadata information about the type of XHRs and therefore does not have any mechanisms to select the required ones. 14:59:03 ]] 15:02:58 youenn has joined #webtv 15:03:23 colin: can understand the need but how to implement it? 15:03:43 s/how to implement it?/not sure how to implement it/ 15:06:22 kaz: one possibility is bringing the requirements to the WoT WG later 15:10:34 alex: problem with buffering, media segment, etc. 15:11:19 ... would people to review this use case 15:11:27 colin: will go through this uc again 15:12:31 topic: Accessibility 15:13:33 chris: still struggling with what is expected for accessibility for cloud browser 15:15:10 colin: maybe there are 2 different levels: OS level and DOM level 15:15:23 chris: any suggestions? 15:16:09 colin: for desktop PC browsers, there is alternative text 15:16:24 ... how can we do that with cloud browser? 15:17:30 q+ 15:17:54 colin: there is an "Introduction" page: https://www.w3.org/2011/webtv/wiki/Main_Page/Cloud_Browser_TF/Introduction_cloud_browser 15:18:11 chris: each kind of operation 15:18:17 ... how to maximize the availability 15:20:54 kaz: currently the topics are rather list of keywords 15:21:13 ... maybe you could elaborate concrete use case description, Chris 15:21:38 ... also we could see the Media Accessibility User Requirements as the starting point: https://www.w3.org/TR/media-accessibility-reqs/ 15:21:42 topic: TPAC 2017 15:21:50 colin: are you going to attend TPAC 2017? 15:21:58 alex: still checking 15:23:08 kaz: Media & Entertainment IG will have its f2f meeting on Monday, Nov. 6th 15:23:42 ... and we're expected to have a section on cloud browser there 15:24:09 colin: agenda decided? 15:24:19 kaz: the IG Chairs are generating the initial agenda 15:24:35 ... and will have a whole IG call shortly 15:24:51 q? 15:24:58 q- 15:25:22 topic: Next call 15:25:27 alex: next call in 2 weeks 15:25:49 [adjourned] 15:25:53 rrsagent, make log public 15:25:57 rrsagent, draft minutes 15:25:57 I have made the request to generate http://www.w3.org/2017/06/28-webtv-minutes.html kaz 15:26:30 kaz are you still online? 15:26:44 rrsagent, stop