Re: revised recording proposal

On 11/19/2012 10:14 PM, Jim Barnett wrote:
>
> Here's my latest revision of the recording proposal, based on 
> discussion in Lyon and on the list.  The main difference from the 
> previous proposal is that I've moved recording into its own 
> MediaRecorder class, with a constructor that takes a MediaStream as an 
> argument.  I've kept a single record function with an optional 
> TimeSlice argument, because that seemed to be the most popular 
> choice.  There are questions scattered throughout in brackets [].    
> The treatment of errors is extremely vague, but I think that's a 
> reflection of where we are.
>
> Please send me any comments.
>
> -Jim
>
thanks for supplying this!
I like it - and I think it's implementable.

Some comments, worries and nits:

- the text for "record" refers to "raise a recordingerror event", but 
there is no "onrecordingerror" event handler. Neither is the 
"onrecordingwarning" specified in 1.5
- The term "The UA /must/ record each Track within the MediaStream 
separately" is ambiguous to me. For instance, stereo encoding as a+b / 
a-b combo - is that "separate" or not? I think "in such a way that the 
original tracks can be retrieved at playback time" might be less ambiguous.
- Does stopRecording() cause the UA to fire a "dataavailble" event in 
all cases, even if recording hasn't started yet? (I think so, for 
consistency)
- Do we need a "setSyncPoint()" operator and a "syncpoint" signal, so 
that the client can tell the recorder to insert a point at which a 
recording can be broken up (typically a new I-frame)?
- Why does it make sense to set audiorecordingformat and 
videorecordingformat separately? I know we need to support container 
formats with options for codecs, but I don't think these are independent 
entities - having a "parametervalues" argument might be a cleaner way to 
do it.

But I think this is good enough for a first version of a document - 
please format it and send it in, and we can start the process of asking 
Dom how we do a FPWD publication of it!

               Harald