Re: [xrblock] WGLC for draft-ietf-xrblock-rtcp-xr-loss-conceal-05

Qin,

Makes sense, thanks. 

Colin

On 18 Jun 2013, at 04:20, Qin Wu wrote:
> Good points. I fully agree.
> However changing measurement unit from RTP timestamp unit to ms may cause measurement unit inconsistency.
> 
> Taking loss concealment metrics block as an example, both 32 bit On-time Playout Duration field and 16 bit Mean Playout Interrupt Size uses the same measurement unit (ms), if we only change measurement unit for all 32 bit fields that carry loss concealment metrics to RTP timestamp unit, this cause
> Some fields in the block use "ms" as unit, some field uses RTP timestamp unit.
> 
> Taking concealment seconds metrics as another example, "SCS Threshold" field also uses milliseconds as unit.
> 
> Let me know what you think of this?
> 
> Regards!
> -Qin
> -----Original Message-----
> From: Colin Perkins [mailto:csp@csperkins.org] 
> Sent: Tuesday, June 18, 2013 6:10 AM
> To: Qin Wu
> Cc: Shida Schubert; xrblock-chairs; xrblock
> Subject: Re: [xrblock] WGLC for draft-ietf-xrblock-rtcp-xr-loss-conceal-05
> 
> Qin,
> 
> The length of time represented by an audio payload tends to be an integer number of milliseconds for frame-based codecs, but can have an arbitrary length for sample-based codecs. Using RTP timestamp units might allow you to precisely match up the timings, if that matters. Plus, don't you have RTP timestamp units, but would need to convert to milliseconds?
> 
> Colin
> 
> 
> 
> On 13 Jun 2013, at 06:34, Qin Wu wrote:
>> Colin,
>> Yes, you are right.
>> The length of time represented by audio playload in the RTP packet is usually measured using ms.
>> Another rationale is concealment metrics are just terminal related end system metrics and its calculation does not need to rely on RTP timestamp in the RTP packet.
>> 
>> Regards!
>> -Qin
>> -----Original Message-----
>> From: xrblock-bounces@ietf.org [mailto:xrblock-bounces@ietf.org] On Behalf Of Colin Perkins
>> Sent: Wednesday, June 12, 2013 12:02 AM
>> To: Shida Schubert
>> Cc: xrblock-chairs; xrblock
>> Subject: Re: [xrblock] WGLC for draft-ietf-xrblock-rtcp-xr-loss-conceal-05
>> 
>> Shida,
>> 
>> I've read the draft, and believe it's in reasonable shape to progress. I would be interested in hearing the authors' rationale for choosing ms as the measurement unit rather than RTP timestamp units, however. It would seem that there might be an argument for using RTP timestamp units, so the reports can exactly line-up with the audio data in the RTP packets.
>> 
>> Colin
>> 
>> 
>> 
>> On 29 May 2013, at 17:53, Shida Schubert wrote:
>>> This is an announcement of a 2 weeks XRBLOCK WG last call on 
>>> "Report Block for Concealment metrics Reporting on Audio Applications" 
>>> prior to requesting publication of the document as a proposed standard. 
>>> 
>>> As per discussion at the last meeting, we are running a second 
>>> WGLC on this draft.
>>> 
>>> Please send your comments, including nits, to the list by the
>>> 
>>> 12th of June
>>> 
>>> If you read the draft and you see no issues, concerns, or nits, please
>>> express the fact that you have no issue progressing the draft on the
>>> list as well. 
>>> 
>>> The latest version can be found here:
>>> 
>>> http://tools.ietf.org/html/draft-ietf-xrblock-rtcp-xr-loss-conceal-05
>>> 
>>> Regards
>>> 
>>> Shida as co-chair
>>> _______________________________________________
>>> xrblock mailing list
>>> xrblock@ietf.org
>>> https://www.ietf.org/mailman/listinfo/xrblock
>> 
>> 
>> 
>> -- 
>> Colin Perkins
>> http://csperkins.org/