W3C home > Mailing lists > Public > public-media-capture@w3.org > August 2013

Re: Width/height in MediaStream Recorder

From: Stefan Håkansson LK <stefan.lk.hakansson@ericsson.com>
Date: Wed, 7 Aug 2013 14:43:20 +0000
To: Jim Barnett <Jim.Barnett@genesyslab.com>
CC: "public-media-capture@w3.org" <public-media-capture@w3.org>
Message-ID: <1447FA0C20ED5147A1AA0EF02890A64B1C350518@ESESSMB209.ericsson.se>
On 2013-08-07 16:16, Jim Barnett wrote:
> I think that the more general question is whether it is sufficient to
> have capabilities/settings only at the Stream level, or if users will
> want to set them on the Track level.  I suppose that we could say
> that for Recording we support only Stream-level capabilities, but I'm
> not sure what use cases that would block.

In a sense it is the more general question just as you say, but what 
capabilities/settings at track level, apart from those that can already 
be dealt with on the MediaStreamTrack itself, would we see need for?

Width, height, aspect ratio, frameRate is already available at track 
level according to the current proposal in "Media Capture and Streams". 
But perhaps there are other capabilities, related to recording, that 
must be exposed?


> - Jim
> -----Original Message----- From: Stefan Håkansson LK
> [mailto:stefan.lk.hakansson@ericsson.com] Sent: Wednesday, August 07,
> 2013 4:59 AM To: Jim Barnett Cc: public-media-capture@w3.org Subject:
> Re: Width/height in MediaStream Recorder
> On 2013-08-06 16:07, Jim Barnett wrote:
>> This could be a fairly general problem.  We also list MimeType as
>> an attribute.  Couldn't different Tracks have different mime
>> types? Different frame rates?  Couldn't just about anything differ
>> between tracks?
> Regarding mime-types, isn't that something that is decided by the
> recorder (as long as they are just MediaStreamTracks, there are no
> mime-types involved)? So basically we could decide that the recorder
> uses one mime type that covers the entire MediaStream being
> recorded.
> I guess that in principle frame rate could differ between tracks, but
> that is nothing that is exposed in the Recorder API as far as I can
> tell.
> Could we not just remove the imageHeight/Width attributes (and the
> possibility to set them)? You can find out by attaching the recorded
> blob to a media element, and to set you could use constraints on the
> tracks of the MediaStream that you want to record. (I'm probably
> missing some important use case here.)
> Stefan
>> - Jim
>> -----Original Message----- From: Stefan Håkansson LK
>> [mailto:stefan.lk.hakansson@ericsson.com] Sent: Tuesday, August
>> 06, 2013 8:20 AM To: public-media-capture@w3.org Subject:
>> Width/height in MediaStream Recorder
>> Hi,
>> (sorry if I miss something obvious) the MediaRecorder has
>> imageWidth and imageHeight readonly attributes. What will these
>> represent in cases when there is more than one VideoStreamTrack in
>> the MediaStream being recorded?
>> Stefan

Received on Wednesday, 7 August 2013 14:43:44 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 16:26:18 UTC