Pull Request Overview

Opened on September 20, 2026
Status Open
Commit count 2 with first commit September 20, 2026

Total Delta

218 Total Diff Delta

Open Days

Open 40 weekdays

Test Delta

0 Diff Delta in Test Files

Breakdown by Phase

How long has this pull request spent in each phase of its lifecycle?

Fraction of total time	Business days	Phase
	0.0 days	Authoring 1 commit before pull request opened for review
	0.2 days	Awaiting first review
	39.7 days	Revising work with 1 commit in response to 2 reviews that left 7 comments

Total time for pull request still awaiting merge (longer than repo's target): 39.9 business days

Add "Enable Audio Ducking" checkbox

This change mostly reverts a4be7ad3f07d6ad2051c017c6b9acda36946a04d

Instead, it adds a checkbox to enable/disable the feature. When disabled, the ducking controls are disabled.

Disabled:

Enabled:

I don't feel strongly about this change. But there were enough comments from the beta that I thought it was worth responding.

Comments Threads Pending Resolution

ljharb reviewed on September 21, 2026

ljharb left a comment

## Copilot review overview

### 🟡 Changes recommended

Threshold state synchronization and legacy shadow persistence issues remain unresolved.

*Get a fresh assessment by requesting another Copilot review.*

**Review effort:** Lite
**Findings:** 3 · 1

Open (4)

- [Restore real threshold when shadow property is missing](#discussion_r4058775339) · New
- [Persist threshold when disabling ducking on legacy transitions](#discussion_r4058775357) · New
- [Keep ducking enabled state consistent when threshold is zero](#discussion_r4058775373) · New
- [Add entry logging to redo()](#discussion_r4058775381) · New

What changed in this PR

Adds an opt-in audio-ducking checkbox, shadow threshold handling, undo support, and simplified spinner behavior.

**Changes:**
- Adds checkbox-controlled ducking UI and threshold synchronization.
- Adds duck-threshold undo/redo handling.
- Removes obsolete spinner override functionality.

| File | Summary |
|---|---|
| `src/widgets/trackpropertieswidget.ui` | Adds the ducking checkbox a...

src/commands/timelinecommands.cpp

    setText(QObject::tr("Change track duck threshold"));

    QScopedPointer<Mlt::Transition> transition(getMixTransitionByTrackIndex(m_trackIndex));

    if (transition && transition->is_valid()) {

        m_oldValue = transition->get_double("duck_threshold_shadow");

        m_oldRealValue = transition->get_double("duck_threshold");

src/widgets/trackpropertieswidget.cpp

                                                                : 0.0,

                                                            checked

                                                                ? tr("Enable Track Audio Ducking")

                                                                : tr("Disable Track Audio Ducking"),

                                                            false);

src/widgets/trackpropertieswidget.cpp

        auto command

            = new Timeline::ChangeDuckThresholdCommand(transition->get_b_track(),

                                                       value,

                                                       ui->duckEnabledCheckBox->isChecked());

        connect(command, SIGNAL(valueChanged(double)), SLOT(onDuckThresholdShadowChanged(double)));

src/commands/timelinecommands.cpp

    }

}

void ChangeDuckThresholdCommand::redo()

{

ddennedy reviewed on September 20, 2026

ddennedy left a comment

Ugh, I just noticed that some field names are capitalized all words. Again, see [our UI conventions](https://shotcut.org/notes/ui-conventions/).

I inclined to prefer this because the current approach with OFF and need to slide to turn it off is unconventional. However, as an additional row it looks awkwardly placed and redundant. How about a checkbox at the start of the heading?

☑️ **Automatic Audio Ducking**

You can ignore the build failures as Debian unstable being unstable.

Resolved Comment Threads

No resolved comments have been left on this PR.

	2426		`setText(QObject::tr("Change track duck threshold"));`
	2427		`QScopedPointer<Mlt::Transition> transition(getMixTransitionByTrackIndex(m_trackIndex));`
	2428		`if (transition && transition->is_valid()) {`
	2429		`m_oldValue = transition->get_double("duck_threshold_shadow");`
	2430		`m_oldRealValue = transition->get_double("duck_threshold");`

	324		`: 0.0,`
	325		`checked`
	326		`? tr("Enable Track Audio Ducking")`
	327		`: tr("Disable Track Audio Ducking"),`
	328		`false);`

	338	`auto command`
	339	`= new Timeline::ChangeDuckThresholdCommand(transition->get_b_track(),`
298	340	`value,`
	341	`ui->duckEnabledCheckBox->isChecked());`
	342	`connect(command, SIGNAL(valueChanged(double)), SLOT(onDuckThresholdShadowChanged(double)));`

	2431		`}`
	2432		`}`
	2433
	2434		`void ChangeDuckThresholdCommand::redo()`
	2435		`{`