re-evaluate minimum bitrate for 640xsomething resolution

RESOLVED FIXED in Firefox 63

Status

()

P2
normal
Rank:
15
RESOLVED FIXED
8 months ago
7 months ago

People

(Reporter: fippo, Assigned: fippo)

Tracking

Trunk
mozilla63
Points:
---

Firefox Tracking Flags

(firefox63 fixed)

Details

Attachments

(2 attachments, 1 obsolete attachment)

(Assignee)

Description

8 months ago
followup on https://bugzilla.mozilla.org/show_bug.cgi?id=1474661#c22

I think the minimum bitrate should not be 300kbps but 150kbps, same as in webrtc.org. Otherwise there is a gap between the maximum bitrate the 320x180 layer is going to send (150kbps) and where the 640x360 layer starts encoding.
And the maximum REMB estimate one can get from these 150kbps is around 260kbps which means one can get "stuck" in the low-resolution layer.

From what I can see this does not seem to affect non-simulcast streams, https://webrtc.github.io/samples/src/content/peerconnection/bandwidth/ works fine (when modified to use 640x360) even at 125kbps.
(Assignee)

Comment 1

8 months ago
Posted patch minbitrate.patch (obsolete) — Splinter Review
Attachment #8998454 - Flags: review?(docfaraday)
Assignee: nobody → fippo
Status: NEW → ASSIGNED
Rank: 15
Priority: -- → P2
Comment on attachment 8998454 [details] [diff] [review]
minbitrate.patch

Review of attachment 8998454 [details] [diff] [review]:
-----------------------------------------------------------------

::: media/webrtc/signaling/src/media-conduit/VideoConduit.cpp
@@ +1634,1 @@
>    {tl::Max<MB_OF(400, 240), MB_OF(352, 288)>::value, KBPS(200), KBPS(300), KBPS(1300)}, // VGA, WVGA

The min for 480x270 is lower than the min for the next resolution down.
Attachment #8998454 - Flags: review?(docfaraday) → review-
(Assignee)

Comment 3

8 months ago
also moved the WVGA a bit. Not sure if 125k is a good minimum bitrate but afaics the min bitrate seems unused for non-simulcast. Maybe it is only used with googSuspendBelowMinBitrate as described in http://www.rtcbits.com/2016/11/controlling-bandwidth-usage-in-webrtc.html ?
Attachment #8998779 - Flags: review?(docfaraday)
(Assignee)

Updated

8 months ago
Attachment #8998454 - Attachment is obsolete: true
Comment on attachment 8998779 [details] [diff] [review]
minbitrate2.patch

Review of attachment 8998779 [details] [diff] [review]:
-----------------------------------------------------------------

This seems to work ok.
Attachment #8998779 - Flags: review?(docfaraday) → review+
(Assignee)

Comment 5

7 months ago
bwc: can you help me land that please?
Flags: needinfo?(docfaraday)
(Assignee)

Updated

7 months ago
Summary: re-evaluate simulcast bitrates for 640x360 resolution → re-evaluate minimum bitrate for 640xsomething resolution

Updated

7 months ago
Flags: needinfo?(docfaraday)
Keywords: checkin-needed

Comment 8

7 months ago
Pushed by apavel@mozilla.com:
https://hg.mozilla.org/integration/mozilla-inbound/rev/dc2b23ed78c7
change minimum bitrate for VGA to 150kbps r=bwc
Keywords: checkin-needed

Comment 9

7 months ago
bugherder
https://hg.mozilla.org/mozilla-central/rev/dc2b23ed78c7
Status: ASSIGNED → RESOLVED
Last Resolved: 7 months ago
status-firefox63: affected → fixed
Resolution: --- → FIXED
Target Milestone: --- → mozilla63
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