Two related changes to PacketQueue::clearPackets, called by the analysis
thread on every video packet:
1. Lock-free call-site gate (should_try_clear) on the analysis path.
In keep_keyframes mode the existing early-return at the top of
clearPackets discards most non-keyframe video packets after acquiring
the queue mutex. Add an inline lock-free check at the call site so
non-keyframe packets skip the mutex acquire entirely. clear_packets_pending_
is now std::atomic<bool> so it can be read without the lock; a stale
read is harmless (at worst we make one extra cheap early-returning call).
The !keep_keyframes path always returns true from the gate because that
mode pops one packet at a time on every video packet.
2. Iterator boundary in the scan loop changed from >= to >. Setting
next_front to a packet that an iterator points at is safe because
clearPackets deletes strictly before next_front, so the iterator's
own packet stays in the queue. Previously, an event-start (or other)
iterator landing exactly on a keyframe blocked the leading GOP from
being dropped until the iterator advanced; now we can include that
keyframe as next_front while the iterator continues to point at it.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Remove per-packet ZMPacketLock trylock() from clearPackets() scan loops
and queuePacket() GOP deletion — the iterator check is sufficient since
threads only access packets through their own shared_ptr.
Add a monotonic uint64_t queue_index to ZMPacket, assigned on enqueue.
clearPackets() now finds the earliest iterator position with a single
min() over the 2-3 iterators, then uses one integer comparison per
scanned packet instead of walking all iterators per packet.
Defer packet destruction outside the mutex in both clearPackets() and
queuePacket() by collecting removed shared_ptrs into a local vector
and releasing the lock before they are destroyed.
Raise per-packet deletion Debug(1) to Debug(4) in both paths.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Event::Run could block indefinitely in PacketQueue methods during normal
event closing (closeEvent from analysis thread), because their wait
predicates only check deleting/zm_terminate, not Event's terminate_ flag.
Three changes fix this:
- get_packet_no_wait: return immediately when iterator at end instead of
blocking on condition variable (makes it truly non-blocking)
- Event::Run: use increment_it(wait=false) since deletePacket can advance
the iterator to end() during AddPacket_ without the queue lock
- Event::Stop: call packetqueue->notify_all() to wake timed waits so
Run() checks terminate_ promptly
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add a uint64_t queue_index field to ZMPacket, assigned by PacketQueue
on enqueue via a monotonic counter. This lets clearPackets() find the
earliest iterator-pointed packet with a single min() over the 2-3
iterators, then check each scanned packet with one integer comparison
instead of searching a vector of shared_ptrs.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Remove per-packet ZMPacketLock trylock() from clearPackets() scan loops
and queuePacket() GOP deletion — the iterator check is sufficient since
threads only access packets through their own shared_ptr after obtaining
it from the queue.
Pre-compute the set of iterator-pointed packets once before scanning
instead of calling is_there_an_iterator_pointing_to_packet() per packet,
reducing O(packets * iterators) to O(iterators) for the lookup setup.
Batch packet destruction outside the mutex by collecting removed
shared_ptrs into a local vector and releasing the lock before they are
destroyed, so expensive ZMPacket destructors don't block queuePacket()
and get_packet_and_increment_it().
Raise per-packet deletion Debug(1) to Debug(4) to cut string formatting
on the hot path.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
The backward walk loop exits when the iterator reaches pktQueue.begin()
without counting that packet as a video frame. This off-by-one causes
the "Hit end of packetqueue before satisfying pre_event_count" warning
even when the queue has enough packets. Check the begin packet after
the loop exits.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Monitor::Decode():
- Reorganize into 5 clear phases with descriptive comments
- Phase 1: Receive decoded frame from decoder
- Phase 2: Get and send new packet to decoder
- Phase 3: Convert decoded frame to Image
- Phase 4: Prepare Y-channel for analysis
- Phase 5: Process RGB image (deinterlace, rotate, privacy, timestamp)
- Extract applyOrientation() and applyDeinterlacing() helper functions
- Keep slow send_packet detection timing for diagnostics
PacketQueue locking fixes:
- Move lock acquisition before accessing shared state in queuePacket()
- Keep lock held while iterating in stop()
- Add lock to addStream()
- Remove duplicate packet_counts allocation in clear()
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
