答复: 答复: MediaStreamTrack behaviuor



Yang
Huawei


> -----邮件原件-----
> 发件人: Stefan Hakansson LK [mailto:stefan.lk.hakansson@ericsson.com]
> 发送时间: 2012年7月6日 15:01
> 收件人: Sunyang (Eric)
> 抄送: public-media-capture@w3.org
> 主题: Re: 答复: MediaStreamTrack behaviuor
> 
> On 07/05/2012 11:13 AM, Sunyang (Eric) wrote:
> > Are you sure?
> 
> I'm sure that was the intention when it was written :-).
> 
> >
> > Since we do not construct new mediastreamtrack, so I mute it in 1st
> mediastream, it will change the object status.
> > Since it is the same object referenced in 2nd mediastream, so I think it is
> also muted.
> >
> > SO do you mean that if we construct a new mediastream using existing
> mediastreamtrack, it will be a new object?
> Yes, that is what I mean.
[yang] I mean how many mediastreamtrack copies there are after construct a new mediastream using existing mediastreamtrack?

> 
> >
> > Yang
> > Huawei
> >
> >
> > -----邮件原件-----
> > 发件人: Stefan Hakansson LK [mailto:stefan.lk.hakansson@ericsson.com]
> > 发送时间: 2012年7月4日 21:43
> > 收件人: public-media-capture@w3.org
> > 主题: Re: MediaStreamTrack behaviuor
> >
> > On 07/04/2012 02:35 PM, Tommy Widenflycht (ᛏᚮᛘᛘᚤ) wrote:
> >> Hi,
> >> I am a bit confused regarding the latest draft regarding how
> >> MediaStreamTracks should behave when they are part of more than one
> >> MediaStream.
> >>
> >> It used to be that when a MediaStream was created with a list of Tracks
> >> one created new tracks that had the same underlying data source as the
> >> input tracks. Basically one cloned the tracks.
> >>
> >> Now the draft says that the new MediaStream should add the same
> Tracks
> >> to its lists. That means that the same Track can now belong to more than
> >> one MediaStream. This has an unfortunate effect that if one disables a
> >> Track, the Track gets disabled in all MediaStreams. It is no longer
> >> possible to have independent enabled stated, and for example this basic
> >> use case is impossible:
> >>
> >> A LocalMediaStream is created by getUserMedia. The user creates a new
> >> MediaStream with the video track from the LMS. The LMS is attached to a
> >> video tag for self view, and the MS is added to a PeerConnection. The
> >> user wants to implement a video mute function for outgoing video and
> >> therefore disables the video track in the MS. This now disables the
> >> video track in the LMS as well whereas before this was doing the right
> >> thing.
> >>
> >> What is the reasoning behind this change?
> >
> > To me it sounds like an editing mistake. One of the purposes of being
> > able to create new MS's from track(lists) of existing MS's is to be able
> > to disable a specific track in one MS without disabling the "same" track
> > (i.e. the track representing the same source) in the other MS.
> >
> > So, the way it used to be is the way it should be IMO.
> >
> > Stefan
> >
> >>
> >> /Tommy
> >>
> >> --
> >> Tommy Widenflycht, Senior Software Engineer
> >> Google Sweden AB, Kungsbron 2, SE-11122 Stockholm, Sweden
> >> Org. nr. 556656-6880
> >> And yes, I have to include the above in every outgoing email according
> >> to EU law.
> >
> >
> >
>

Received on Friday, 6 July 2012 08:50:40 UTC