1283020 - Change the various latency API to use frames instead of milliseconds

Status: RESOLVED FIXED

(Core :: Audio/Video: cubeb, defect, P2)

Description

[Paul Adenot (:padenot)]

The latency situation has evolved a lot since the early days, and now we need a tighter control over the latency numbers, both when getting the minimum latency supported on the current configuration and passing it when initializing a new stream.

Platform APIs usually use frames, and using milliseconds in Gecko forces conversion and unnecessary rounding.

Considering that having the wrong buffer size can make us not go into a mixer fast-path (for example, android is very picky about that), we should switch to using frames in:

- cubeb_device_info
- cubeb_get_min_latency
- cubeb_stream_init

Comment 1

[Paul Adenot (:padenot)]

Attachment: Bug 1283020 - Update Gecko to reflect cubeb changes: use frames instead of milliseconds for latency.

Review commit: https://reviewboard.mozilla.org/r/65518/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/65518/

Comment 2

[Alex Chronopoulos [:achronop]]

Comment on attachment 8772781 [details]
Bug 1283020 - Update Gecko to reflect cubeb changes: use frames instead of milliseconds for latency.

https://reviewboard.mozilla.org/r/65518/#review62504

Looks good, thanks!

::: dom/media/AudioStream.cpp:366
(Diff revision 1)
>      return NS_ERROR_FAILURE;
>    }
>  
>    cubeb_stream* stream = nullptr;
> +  /* Convert from milliseconds to frames. */
> +  uint32_t latency_frames = CubebUtils::GetCubebLatency() * aParams.rate / 1000;

We could add the trsform from ms to frames inside CubebUtils::GetCubebLatency method

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/344300260f4c
Update cubeb consumers to pass in latency in frames and not in ms.  r=achronop

Comment 4

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

Backed out in https://hg.mozilla.org/integration/mozilla-inbound/rev/d2ba56fc82b6 because it (or bug 1285541) seems to have caused a frequent mochitest(gl) failure: https://treeherder.mozilla.org/#/jobs?repo=mozilla-inbound&fromchange=9f4b5bd8af0c54daafd5e19358e7871f2bd6c2c3&bugfiler&filter-searchStr=10.%20(gl

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/7ba223fde0e0
Update cubeb consumers to pass in latency in frames and not in ms.  r=achronop

Comment 6

[Paul Adenot (:padenot)]

oops, still not merged.

Comment 7

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/7ba223fde0e0