fix(wtv): Set sync_pts alongside min_pts to prevent PTS jump detection #1853
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The previous WTV timing fix (commit 300f8ca) set min_pts and pts_set=2 (MinPtsSet) but didn't set sync_pts. This caused the Rust timing code to detect a massive PTS jump when processing WTV files with large initial timestamps (e.g., files recorded at 18:38:23). The PTS jump detection computes (current_pts - sync_pts), and with sync_pts=0 but current_pts=6039323550 (18:38:23 in PTS units), the difference exceeded MAX_DIF and triggered the jump handling, resulting in empty output. This fix sets sync_pts to the same value as min_pts when first initializing timing, preventing the false PTS jump detection. Test results: - Before: WTV files with large initial PTS produced empty output - After: Timestamps match expected ground truth exactly (e.g., 00:00:00,601 --> 00:00:02,801 for first caption) 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <[email protected]>
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Summary
Fixes a regression introduced in PR #1849 (commit 300f8ca) where WTV files with large initial PTS values would produce empty output.
Root cause: The WTV timing fix set
min_ptsandpts_set=2(MinPtsSet) but didn't setsync_pts. The Rust timing code checks for PTS jumps by computingcurrent_pts - sync_pts, and withsync_pts=0butcurrent_ptsat a large value (e.g., 6039323550 for a file starting at 18:38:23), the difference triggered false PTS jump detection.Fix: Set
sync_ptsto the same value asmin_ptswhen first initializing timing.Test results
Before (master):
Output: Empty file, progress showed
-1118:-23(negative hours!)After (this fix):
00:00:00,601 --> 00:00:02,801✅ Matches expected00:00:02,837 --> 00:00:06,305✅ Matches expected00:00:11,145 --> 00:00:12,411✅ Matches expectedTested on all WTV samples in the test corpus - all produce correct output.
Test plan
🤖 Generated with Claude Code