Find better terms to use in the TSBPD time module.

[maxsharabayko]

The discussion started with PR #3038. The CTsbpdTime uses several terms that are misleading in a way that they don't differ much from each other.

• "TsbPd Time Base" is the time of a local (steady) clock used as a base for TSBPD.
• "Packet TsbPd Base Time" - TSBPD time of a packet without buffering delay and clock drift. Effectively "TsbPd Time Base" + "packet timestamp".
• "Packet TsbPd Time" - packet TSBPD time with buffering delay and clock drift. Effectively "TsbPd Time Base" + "packet timestamp" + "buffering delay" + "clock drift".

As suggested by @ethouris :

Some better term for this value has to be developed. We have:

• Time Base: the time when the connection has started and since when all the time is calculated. Doesn't change during transmission

• Local Time Base - or Shifted Time Base, Earliest Time: The "timespace?" for the time given in 32-bit timestamps which is a sum of the Time Base and N values of the "segment" (which represent a maximum 32-bit time value).

Might be also something like "timespace" or "rollover time base". "Base Time" is simply too similar to "Time Base".

@ethouris @stevomatthews are welcome in this discussion.

[stevomatthews]

No matter what you name these entities, it will be necessary to have an explicit description for each readily available in the code comments and documentation. But, if possible, a simple restructuring of the names might help:

TsbPd Time Base --> TsbPd Time Base Packet TsbPd Base Time --> TsbPd Packet Time Base * Packet TsbPd Time --> TsbPd Packet Time

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From: Maxim Sharabayko @.> Sent: October 8, 2024 10:34 AM To: Haivision/srt @.> Cc: Steve Matthews @.>; Mention @.> Subject: [Haivision/srt] Find better terms to use in the TSBPD time module. (Issue #3043)

The discussion started with PR #3038https://github.com/Haivision/srt/pull/3038. The CTsbpdTime uses several terms that are misleading in a way that they don't differ much from each other.

• "TsbPd Time Base" is the time of a local (steady) clock used as a base for TSBPD.
• "Packet TsbPd Base Time" - TSBPD time of a packet without buffering delay and clock drift. Effectively "TsbPd Time Base" + "packet timestamp".
• "Packet TsbPd Time" - packet TSBPD time with buffering delay and clock drift. Effectively "TsbPd Time Base" + "packet timestamp" + "buffering delay" + "clock drift".

As suggested by @ethourishttps://github.com/ethouris :

Some better term for this value has to be developed. We have:

• Time Base: the time when the connection has started and since when all the time is calculated. Doesn't change during transmission

• Local Time Base - or Shifted Time Base, Earliest Time: The "timespace?" for the time given in 32-bit timestamps which is a sum of the Time Base and N values of the "segment" (which represent a maximum 32-bit time value).

Might be also something like "timespace" or "rollover time base". "Base Time" is simply too similar to "Time Base".

@ethourishttps://github.com/ethouris @stevomatthewshttps://github.com/stevomatthews are welcome in this discussion.

— Reply to this email directly, view it on GitHubhttps://github.com/Haivision/srt/issues/3043, or unsubscribehttps://github.com/notifications/unsubscribe-auth/AGZXHTZME4JTZZOUTSVKYSLZ2PUQBAVCNFSM6AAAAABPSL4KIOVHI2DSMVQWIX3LMV43ASLTON2WKOZSGU3TGMZYGIZTQMI. You are receiving this because you were mentioned.Message ID: @.***>

[maxsharabayko]

@stevomatthews Actually, a good point. Also the "Tsbpd" part is maybe excessive. Class name already assumes the time is TSBPD.

So maybe rename this way:

• CTsbpdTime::getTsbPdTimeBase -> CTsbpdTime::getBaseTime
• CTsbpdTime::getPktTsbPdBaseTime -> CTsbpdTime::getPktBaseTime
• CTsbpdTime::getPktTsbPdTime -> CTsbpdTime::getPktTime

[stevomatthews]

Looks good to me!

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From: Maxim Sharabayko @.> Sent: October 9, 2024 3:58 PM To: Haivision/srt @.> Cc: Steve Matthews @.>; Mention @.> Subject: Re: [Haivision/srt] Find better terms to use in the TSBPD time module. (Issue #3043)

@stevomatthewshttps://github.com/stevomatthews Actually, a good point. Also the "Tsbpd" part is maybe excessive. Class name already assumes the time is TSBPD.

So maybe rename this way:

• CTsbpdTime::getTsbPdTimeBase -> CTsbpdTime::getBaseTime
• CTsbpdTime::getPktTsbPdBaseTime -> CTsbpdTime::getPktBaseTime
• CTsbpdTime::getPktTsbPdTime -> CTsbpdTime::getPktTime

— Reply to this email directly, view it on GitHubhttps://github.com/Haivision/srt/issues/3043#issuecomment-2403321845, or unsubscribehttps://github.com/notifications/unsubscribe-auth/AGZXHT6XK6WN5KPSNFRMVX3Z2WDFFAVCNFSM6AAAAABPSL4KIOVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDIMBTGMZDCOBUGU. You are receiving this because you were mentioned.Message ID: @.***>

[ethouris]

Well, it is definitely better. PktBase, which defines that this is the time base but only for a time extracted from the packet, is different enough from just Base and clear enough.