Re: Encoders (Re: Getting rid of SDP) - Timestamps for media from Cullen Jennings on 2018-03-16 (public-webrtc@w3.org from March 2018)

From: Cullen Jennings <fluffy@iii.ca>
Date: Fri, 16 Mar 2018 11:27:59 +0000
To: Harald Alvestrand <harald@alvestrand.no>
Cc: public-webrtc@w3.org
Message-Id: <9B87EF67-643C-4B45-BCF9-A13BD5E3DEBC@iii.ca>

> On Mar 13, 2018, at 10:37 PM, Harald Alvestrand <harald@alvestrand.no> wrote:
> 
>> * capture time of frame 
> are you thinking SMTPE timecodes (absolute capture time, possibly far in the past for recorded media) or RTP-clock-style "timestamp that can be used for relative positioning in time"?

I have work with SMTPE  timecode a bunch for moving broadcast studios to IP. It seems like a bad match for interactive media. Dropframe handling alone should be enough to convince anyone. I realize broadcast TV needs all that but we don't. 

I would prefer something that is a direct or indirect mapping to NTP time with ms resolution. 

It might seem like something with no leap seconds, like GPS time, was easier to use but I think the operating system end up providing such good support for time with leap seconds that it ends up being easier.

Received on Friday, 16 March 2018 11:28:32 UTC