Add recording to Shared Memory

config.env.example

@@ -131,12 +131,15 @@ FLUSH_EVERY_N_FRAMES=100
 TRACKED_PRUNE_SEC=300
 
 # --- Video recording ---
-# Save annotated frames to segmented MP4 files (true/false)
+# Per-batch video recording — raw frames (no overlay) to shared memory, moved to
+# OUTPUT_DIR on batch close via non-blocking background process (true/false)
 RECORD_VIDEO=false
-# Duration in seconds of each video segment file
-VIDEO_SEGMENT_SEC=3600
 # Output video FPS (fallback if source FPS is unknown or ≤ 1)
 OUTPUT_FPS=15
+# Delay in seconds after batch starts before recording begins (every batch)
+RECORD_DELAY_SECONDS=10
+# Shared memory directory for recording (fast write, moved to OUTPUT_DIR on close)
+RECORD_SHM_DIR=/dev/shm/bytetrack-counter
 
 # --- Live stream snapshot ---
 # Periodically write the latest annotated frame as JPEG for an external web server