autodj: preroll transitions for gapless playback - #16063
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oh right I need to update tests as well |
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Pull request overview
Adds “pre-roll” playback for the incoming deck during AutoDJ so the next track is already running before the crossfader transition starts, reducing audible gaps from playback start latency.
Changes:
- Start the “to” deck ~1s before
fadeBeginPoswhile still inADJ_IDLE, seeking it back so it aligns at fade start. - Add a gtest covering the early-play pre-roll behavior in
FixedFullTrackmode.
Reviewed changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 7 comments.
| File | Description |
|---|---|
| src/library/autodj/autodjprocessor.cpp | Implements early-start logic for the incoming deck during ADJ_IDLE before fading begins. |
| src/test/autodjprocessor_test.cpp | Adds a regression test verifying the pre-roll behavior and that fading still starts at fadeBeginPos. |
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Start playback of incoming tracks before the transition begins, to prevent any audible gap between tracks due to buffer inconsistencies or delays in playback triggering. Tested manually, sounds delicious Signed-off-by: Owen Williams <owilliams@mixxx.org>
Signed-off-by: Owen Williams <owilliams@mixxx.org>
…eek requests. Also removes ADJ_ENABLE_P1PLAYING state, which was unused. Signed-off-by: Owen Williams <owilliams@mixxx.org>
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looks like I have to fix a test |
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This PR is marked as stale because it has been open 90 days with no activity. |
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Signed-off-by: Owen Williams <owilliams@mixxx.org>
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Start playback of incoming tracks about 1.0s (corrected for the exact offset between tracks!) before the transition begins to prevent any audible gap between tracks due to buffer inconsistencies or delays in playback triggering.
Tested manually, sounds delicious. This is best with the following settings:
NOTE: this does not totally work on mp3 tracks, which cannot be sample-exact lengths. Instead, test with wav, aiff, flac, or ogg. "skip silence" mode works a little better, but it's not perfect and sometimes messes up the transitions for non-mp3 tracks. A subsequent PR could introduce a new skip algorithm that takes mp3 frames into account.
Initially created with claude but I edited it a lot since then so now it's all mine.