Re: [whatwg] HTML5 based Eduvid Slidecasting Demo
On Sun, May 22, 2011 at 3:20 AM, Narendra Sisodiya naren...@narendrasisodiya.com wrote: I hope this demo will help to who who want html5 version of slidecasting technique. There is big room or improvement in the codebase. http://code.narendrasisodiya.com/slidecast/demo-slidecasting.html Another Demo - Video + Slides - http://code.narendrasisodiya.com/video-slidecast/demo.html I have support for reading time.xml this time. over the time this will grow and parser for handling a general purpose time.xml will be developed. Blog Entry - http://blog.narendrasisodiya.com/2011/07/html5-based-video-slidecasting-demo.html
Re: [whatwg] HTML5 based Eduvid Slidecasting Demo
On Sun, May 22, 2011 at 6:48 AM, Narendra Sisodiya naren...@narendrasisodiya.com wrote: On Sun, May 22, 2011 at 8:22 AM, Silvia Pfeiffer silviapfeiff...@gmail.comwrote: This is a pretty awesome way to publish a record of your slide presentation. I am working to create software to automate the Timing process.. I did automated timing long back when I started Eduvid - http://wiki.techfandu.org/eduvid/Eduvid-0.011/wiki-eduvid-slideshow.html Hopefully I will be able to create better software where when you click next/forward, your timings will be saved alongwidth your slidenumber. Hey Narendra! When I found out about your effort I wanted to tell you about mine. I'm building something similar, but instead of only doing it offline, I want the same, only live. So, video (or just audio, as you say) and the slide sent in real time. My big problem is obviously buffering (and thus latency) of the video. Because of this extremely unpredictable sending, it's not very easy to sync the slides to the video. I'm pushing out new pictures realtime, but it comes out waay to early for most. I'll continue to follow your project. My initial demo isn't up any more, so I've got nothing interesting at all, but it is called Errantia and lives here http://gitorious.org/errantia Anyway, I'm interested in knowing if you need to have live syncing later. If so, we'd need to get startTimeOffset implemented in the browsers. Mozilla will wait «until things like multitrack, media controller, streams, etc are less of a moving target». But WebKit may implement it, but I guess they need a test case. So I need a test case. Also heard that Microsoft is very interested to implement features that have test cases, and maybe even be first (!) because of that. -- Beste helsing, Odin Hørthe Omdal odin.om...@gmail.com http://velmont.no
Re: [whatwg] HTML5 based Eduvid Slidecasting Demo
On Sun, May 22, 2011 at 3:03 PM, Narendra Sisodiya naren...@narendrasisodiya.com wrote: infact I too want to do same.. Cool! Basically you want to send slides (via websocket or comet) and sync with video.. Yes. My old system (early Errantia) did that, using comet. Here is the mistake. Sending Slides in real time has no use. Please do not take me wrong. Basically in almost any conference or workshop, presenter already has slides ready. So if something is ready then you can directly push it to user. send video/audio in real time. You misunderstand :-) The slides are no problem at all, I upload them to the server, then when done it sends a Comet PUSH to the clients which tells them, a new slide resides at http://example.com/images/test-conference/14.jpg . So that part is working swell. Also, I send the time when the slide appeared. However, the syncing to the video/audio is the impossible part, because there's no way for the browser to know where the video is in time/place **in a live setting**, you can very easily do this with archived video, it's just to read currentTime. We had a discussion about this, and that was why startOffsetTime made it into the spec: http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2010-May/thread.html#26342 As you see, there are lots of buffering of video. And such, different people will be different places in the real time video. So I'm watching live and that's only one minute off, whilst a friend is watching via wireless internet and is a full 10 minutes off because of his buffering etc, etc. In order to sync slides to the video/audio in such places (when people connect 10 minutes into the video and get a new currentTime = 0 at that time), you need a static reference point, but as of now; all time is still relative. Getting startOffsetTime will get us a static time to know when we're going to show the new slides (which will also have a datetime field for syncing). So , No need to send slides in real time.. Send all slides at once.. and then keep on sending the configurations I will also try to work on this... Well, for some conferences this won't work, and I already have code to do that live, so I don't need to send slides afterwards. Anyway, both ways work. But you need to know where people are in the video in order to sync to the slides; and that's where startOffsetTime come in. Alternatively you might try to control the buffers/caches, but that's not always possible. I've tried before, and can't really get it thight enough, there's too many variables, and Icecast might not be able to tweak itself to make a really good low latency low buffering live sending. -- Beste helsing, Odin Hørthe Omdal odin.om...@gmail.com http://velmont.no
Re: [whatwg] HTML5 based Eduvid Slidecasting Demo
On Sun, May 22, 2011 at 7:19 PM, Odin odin.om...@gmail.com wrote: On Sun, May 22, 2011 at 3:03 PM, Narendra Sisodiya naren...@narendrasisodiya.com wrote: infact I too want to do same.. Cool! Basically you want to send slides (via websocket or comet) and sync with video.. Yes. My old system (early Errantia) did that, using comet. Here is the mistake. Sending Slides in real time has no use. Please do not take me wrong. Basically in almost any conference or workshop, presenter already has slides ready. So if something is ready then you can directly push it to user. send video/audio in real time. You misunderstand :-) The slides are no problem at all, I upload them to the server, then when done it sends a Comet PUSH to the clients which tells them, a new slide resides at http://example.com/images/test-conference/14.jpg . So that part is working swell. Also, I send the time when the slide appeared. However, the syncing to the video/audio is the impossible part, because there's no way for the browser to know where the video is in time/place **in a live setting**, you can very easily do this with archived video, it's just to read currentTime. We had a discussion about this, and that was why startOffsetTime made it into the spec: http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2010-May/thread.html#26342 As you see, there are lots of buffering of video. And such, different people will be different places in the real time video. So I'm watching live and that's only one minute off, whilst a friend is watching via wireless internet and is a full 10 minutes off because of his buffering etc, etc. In order to sync slides to the video/audio in such places (when people connect 10 minutes into the video and get a new currentTime = 0 at that time), you need a static reference point, but as of now; all time is still relative. Getting startOffsetTime will get us a static time to know when we're going to show the new slides (which will also have a datetime field for syncing). Yes, I got your point.. I am sorry, I misunderstood your email. Also I was not aware of problems in Live Video... So , No need to send slides in real time.. Send all slides at once.. and then keep on sending the configurations I will also try to work on this... Well, for some conferences this won't work, and I already have code to do that live, so I don't need to send slides afterwards. Anyway, both ways work. But you need to know where people are in the video in order to sync to the slides; and that's where startOffsetTime come in. Alternatively you might try to control the buffers/caches, but that's not always possible. I've tried before, and can't really get it thight enough, there's too many variables, and Icecast might not be able to tweak itself to make a really good low latency low buffering live sending. -- Beste helsing, Odin Hørthe Omdal odin.om...@gmail.com http://velmont.no -- ┌─┐ │Narendra Sisodiya │http://narendrasisodiya.com └─┘
[whatwg] HTML5 based Eduvid Slidecasting Demo
I hope this demo will help to who who want html5 version of slidecasting technique. There is big room or improvement in the codebase. http://code.narendrasisodiya.com/slidecast/demo-slidecasting.html Thanks -- ┌─┐ │Narendra Sisodiya │http://narendrasisodiya.com └─┘
Re: [whatwg] HTML5 based Eduvid Slidecasting Demo
This is a pretty awesome way to publish a record of your slide presentation. It would, for example, be cool to use the slide deck at http://slides.html5rocks.com/ with popcorn.js in the way that you're proposing. I could, for example, imagine it working well with something like my talk at http://www.youtube.com/watch?v=_kazYydCmQw and the slides at http://www.html5videoguide.net/presentations/HTML5_Video_LCA2011/ . I should take some time to set that up... Cheers, Silvia. On Sun, May 22, 2011 at 7:50 AM, Narendra Sisodiya naren...@narendrasisodiya.com wrote: I hope this demo will help to who who want html5 version of slidecasting technique. There is big room or improvement in the codebase. http://code.narendrasisodiya.com/slidecast/demo-slidecasting.html Thanks -- ┌─┐ │ Narendra Sisodiya │ http://narendrasisodiya.com └─┘
Re: [whatwg] HTML5 based Eduvid Slidecasting Demo
On Sun, May 22, 2011 at 8:22 AM, Silvia Pfeiffer silviapfeiff...@gmail.comwrote: This is a pretty awesome way to publish a record of your slide presentation. I am working to create software to automate the Timing process.. I did automated timing long back when I started Eduvid - http://wiki.techfandu.org/eduvid/Eduvid-0.011/wiki-eduvid-slideshow.html Hopefully I will be able to create better software where when you click next/forward, your timings will be saved alongwidth your slidenumber. It would, for example, be cool to use the slide deck at http://slides.html5rocks.com/ with popcorn.js in the way that you're proposing. Yes, this is the next process. I am investigating lots of slideshow method. We really need a final version of html based slideshow. I could, for example, imagine it working well with something like my talk at http://www.youtube.com/watch?v=_kazYydCmQw and the slides at http://www.html5videoguide.net/presentations/HTML5_Video_LCA2011/ . I should take some time to set that up... Please try to create, And Then compare the total size of video vs total size of slidecasting. Your demo include videos, so it may be little difficult to create slideshow... using current demo. Also try audacity or/and OggConvert to lower down the size of audio.. This will be a nice case study on how we can send more with less bandwidth. I am particular interested in this type of slidecasting because I do not like Videos for education. Video one single pipe and every information is lost inside it. Having Multi-Pipe delivery for education is better way because you can manipulate any pipe later or serve your pipes according to your bandwidth. imazine your slidecasting contains videos, html5 slides, audio. So when someone sitting in India (with less bandwidth) want to see your demo, he will turn off the video pipe and rest will be delivered to him.. https://docs.google.com/View?id=dhtsnnph_59gt2jjjdjpli=1 Cheers, Silvia. On Sun, May 22, 2011 at 7:50 AM, Narendra Sisodiya naren...@narendrasisodiya.com wrote: I hope this demo will help to who who want html5 version of slidecasting technique. There is big room or improvement in the codebase. http://code.narendrasisodiya.com/slidecast/demo-slidecasting.html Thanks -- ┌─┐ │Narendra Sisodiya │http://narendrasisodiya.com └─┘ -- ┌─┐ │Narendra Sisodiya │http://narendrasisodiya.com └─┘
