1858036 - A-law encoded wave file playback heavily distorted (as if misidentified as μ-law instead)

Status: VERIFIED FIXED

(Core :: Audio/Video: Playback, defect)

Description

[Krzysztof Kaspruk]

Attachment: testcase.zip

Steps to reproduce:

0. Run a Firefox older than changeset: 062a5e5729067f579bd6d1ab2f1a3021d7fd291a (was it 118b09? 117 was fine)
1. Open a website with A-law encoded wave file embedded in <audio> tag - minimal test case included.
2. Press "Play" icon.

---

Bisection with mozregression-GUI led me to these commits:

https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=d1fbe6c1f87656fb4f55677904f55f6df433ea9a&tochange=062a5e5729067f579bd6d1ab2f1a3021d7fd291a

app_name: firefox
build_date: 2023-08-08 14:41:29.819000
build_file: C:\Users\user.mozilla\mozregression\persist\062a5e572906-shippable--autoland--target.zip
build_type: integration
build_url: https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/JEc1-4q5QKKYjLOf-hBr3g/runs/0/artifacts/public%2Fbuild%2Ftarget.zip
changeset: 062a5e5729067f579bd6d1ab2f1a3021d7fd291a
pushlog_url: https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=d1fbe6c1f87656fb4f55677904f55f6df433ea9a&tochange=062a5e5729067f579bd6d1ab2f1a3021d7fd291a
repo_name: autoland
repo_url: https://hg.mozilla.org/integration/autoland
task_id: JEc1-4q5QKKYjLOf-hBr3g

Actual results:

Heavily distorted playback (it sounds as if it was misinterpreted as a μ-law encoded file instead).

Expected results:

Normal playback quality (in this test case Caruso's voice should be soft and clear)

Comment 1

[Mayank Bansal]

ni? :padenot based on the regression range from the reporter.

Comment 2

[Paul Adenot (:padenot)]

Attachment: Bug 1858036 - Fix A-law PCM playback. r?alwu

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/fae684500538
Fix A-law PCM playback. r=alwu

Comment 4

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/fae684500538

Comment 5

[Paul Adenot (:padenot)]

Comment on attachment 9357593 [details]
Bug 1858036 - Fix A-law PCM playback. r?alwu

Beta/Release Uplift Approval Request

• User impact if declined: Some files playback are broken.
• Is this code covered by automated tests?: Yes
• Has the fix been verified in Nightly?: Yes
• Needs manual test from QE?: No
• If yes, steps to reproduce:
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): Trivial patch, unit tests added.
• String changes made/needed:
• Is Android affected?: Yes

Comment 6

[Donal Meehan [:dmeehan]]

Setting Bug 1823953 at the regressor based on the push log in Comment 0, please correct if needed

Comment 7

[Donal Meehan [:dmeehan]]

Comment on attachment 9357593 [details]
Bug 1858036 - Fix A-law PCM playback. r?alwu

Approved for 119.0b9

Comment 8

[Pulsebot]

https://hg.mozilla.org/releases/mozilla-beta/rev/c6bc14a54429

Comment 9

[Hani Yacoub, Desktop QA]

Verified as fixed on Windows 10 x64, macOS 11.6 and on Ubuntu 20.04 x64.