fix: Fix garbled captions from HDHomeRun and I/P-only H.264 streams #1842
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For I/P-only streams (like HDHomeRun recordings), the caption buffer was being flushed on every reference frame (I and P). Since ALL frames in these streams are reference frames, this defeated the caption reordering mechanism, causing garbled output. The fix: - Only flush the buffer and reset reference PTS on IDR frames (NAL type 5), not on P-frames - Initialize currefpts on first frame to avoid huge indices at stream start - Properly flush buffer and reset reference when large PTS gaps are detected This allows P-frames to accumulate in the buffer and be sorted by their PTS-based indices before output. Fixes #1109 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <[email protected]>
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CCExtractor CI platform finished running the test files on linux. Below is a summary of the test results, when compared to test for commit a0809ca...:
Your PR breaks these cases:
NOTE: The following tests have been failing on the master branch as well as the PR:
It seems that not all tests were passed completely. This is an indication that the output of some files is not as expected (but might be according to you). Check the result page for more info. |
Fix clippy warning: variable does not need to be mutable. The current_index variable is only assigned once during initialization and never modified afterward. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <[email protected]>
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Summary
Fixes #1109 - Garbled SRT from transport stream
For I/P-only streams (like HDHomeRun recordings), the caption buffer was being flushed on every reference frame. Since ALL frames in these streams are reference frames, this defeated the caption reordering mechanism, causing garbled output like:
Root Cause
The stream has no B-frames (only I/P frames), but frames arrive in decode order rather than display order. The original code flushed the buffer on every reference frame (I and P), which meant:
The Fix
currefptson first frame to avoid huge indices at stream startThis allows P-frames to accumulate in the buffer and be sorted by their PTS-based indices before output.
Before/After
The output now matches FFmpeg's extraction exactly.
Test plan
🤖 Generated with Claude Code