Semantic Search for Detections (#11899)

* Initial re-implementation of semantic search

* put docker-compose back and make reindex match docs

* remove debug code and fix import

* fix docs

* manually build pysqlite3 as binaries are only available for x86-64

* update comment in build_pysqlite3.sh

* only embed objects

* better error handling when genai fails

* ask ollama to pull requested model at startup

* update ollama docs

* address some PR review comments

* fix lint

* use IPC to write description, update docs for reindex

* remove gemini-pro-vision from docs as it will be unavailable soon

* fix OpenAI doc available models

* fix api error in gemini and metadata for embeddings

frigate/embeddings/__init__.py

@@ -0,0 +1,67 @@
+"""ChromaDB embeddings database."""
+
+import logging
+import multiprocessing as mp
+import signal
+import sys
+import threading
+from types import FrameType
+from typing import Optional
+
+from playhouse.sqliteq import SqliteQueueDatabase
+from setproctitle import setproctitle
+
+from frigate.config import FrigateConfig
+from frigate.models import Event
+from frigate.util.services import listen
+
+logger = logging.getLogger(__name__)
+
+
+def manage_embeddings(config: FrigateConfig) -> None:
+    # Only initialize embeddings if semantic search is enabled
+    if not config.semantic_search.enabled:
+        return
+
+    stop_event = mp.Event()
+
+    def receiveSignal(signalNumber: int, frame: Optional[FrameType]) -> None:
+        stop_event.set()
+
+    signal.signal(signal.SIGTERM, receiveSignal)
+    signal.signal(signal.SIGINT, receiveSignal)
+
+    threading.current_thread().name = "process:embeddings_manager"
+    setproctitle("frigate.embeddings_manager")
+    listen()
+
+    # Configure Frigate DB
+    db = SqliteQueueDatabase(
+        config.database.path,
+        pragmas={
+            "auto_vacuum": "FULL",  # Does not defragment database
+            "cache_size": -512 * 1000,  # 512MB of cache
+            "synchronous": "NORMAL",  # Safe when using WAL https://www.sqlite.org/pragma.html#pragma_synchronous
+        },
+        timeout=max(60, 10 * len([c for c in config.cameras.values() if c.enabled])),
+    )
+    models = [Event]
+    db.bind(models)
+
+    # Hotsawp the sqlite3 module for Chroma compatibility
+    __import__("pysqlite3")
+    sys.modules["sqlite3"] = sys.modules.pop("pysqlite3")
+    from .embeddings import Embeddings
+    from .maintainer import EmbeddingMaintainer
+
+    embeddings = Embeddings()
+
+    # Check if we need to re-index events
+    if config.semantic_search.reindex:
+        embeddings.reindex()
+
+    maintainer = EmbeddingMaintainer(
+        config,
+        stop_event,
+    )
+    maintainer.start()