obs-outputs: File splitting improvements for Hybrid MP4/MOV#13386
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derrod wants to merge 2 commits into
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obs-outputs: File splitting improvements for Hybrid MP4/MOV#13386derrod wants to merge 2 commits into
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PatTheMav
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May 31, 2026
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| const bool final_flush = mux->next_frag_pts == 0; | ||
| const size_t end_offset = final_flush ? 0 : 1; | ||
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| for (size_t i = 0; i < count - end_offset; i++) { |
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If count is the amount of valid encoder packet entries at the memory address of track->packets, then count - 1 is the start address of the last packet.
But when iterating until count - 0 (which would be the case if mux->next_frag_pts is 0), wouldn't you end up with a out-of-bounds access by passing an index past the last element in get_pkt_at?
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No because the loop is still less-than, so it will terminate at count - 1 - end_offset.
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Description
Fixes file splitting by ensurnig the last frame of each part is not dropped, and b-frames are accounted for in the timer
Motivation and Context
Address part of #13374.
Originally, before file splitting was introduced, I made the choice to simple ignore the last frame in the packet queue of the muxer, because frame N+1 is required to properly determine the duration and I figured nobody would notice if their recording is one frame short.
However, when using frame splitting this would result in the last frame before a split being dropped. To fix this, we can simply reuse the previous sample's duration for the final sample in a file. Since OBS only does CFR, they should all be identical anyway.
Additionally I discovered while testing that the first split would always be one GOP too long (e.g. 1m2s instead of 1m) due to the fact that b-frames and negative start DTSes were not accounted for. This is also fixed in this PR.
How Has This Been Tested?
Recorded some files, looked at them frame-by-frame to confirm none are missing now.
Types of changes
Checklist: