Files
Pre_Seg_Server/backend/services/sam2_engine.py
admin f020ff3b4f feat: 打通全栈标注闭环、异步拆帧与模型状态
后端能力:

- 新增 Celery app、worker task、ProcessingTask 模型、/api/tasks 查询接口和 media_task_runner,将 /api/media/parse 改为创建后台任务并由 worker 执行 FFmpeg/OpenCV/pydicom 拆帧。

- 新增 Redis 进度事件模块和 FastAPI Redis pub/sub 订阅,将 worker 任务进度广播到 /ws/progress;Dashboard 后端概览接口改为聚合 projects/frames/annotations/templates/processing_tasks。

- 统一项目状态为 pending/parsing/ready/error,新增共享 status 常量,并让前端兼容归一化旧状态值。

- 扩展 AI 后端:新增 SAM registry、SAM2 真实运行状态、SAM3 状态检测与文本语义推理适配入口,以及 /api/ai/models/status GPU/模型状态接口。

- 补齐标注保存/更新/删除、COCO/PNG mask 导出相关后端契约和模板 mapping_rules 打包/解包行为。

前端能力:

- 新增运行时 API/WS 地址推导配置,前端 API 封装对齐 FastAPI 路由、字段映射、任务轮询、标注归档、导出下载和 AI 预测响应转换。

- Dashboard 改为读取 /api/dashboard/overview,并订阅 WebSocket progress/complete/error/status 更新解析队列和实时流转记录。

- 项目库导入视频/DICOM 后创建项目、上传媒体、触发异步解析并刷新真实项目列表。

- 工作区加载真实帧、无帧时触发解析任务、回显已保存标注、保存未归档 mask、更新 dirty mask、清空当前帧后端标注、导出 COCO JSON。

- Canvas 支持当前帧点/框提示调用后端 AI、渲染推理/已保存 mask、应用模板分类并维护保存状态计数;时间轴按项目 fps 播放。

- AI 页面新增 SAM2/SAM3 模型选择,预测请求携带 model;侧边栏和工作区新增真实 GPU/SAM 状态徽标。

- 模板库和本体面板接入真实模板 CRUD、分类编辑、拖拽排序、JSON 导入、默认腹腔镜分类和本地自定义分类选择。

测试与文档:

- 新增 Vitest 配置、前端测试 setup、API/config/websocket/store/组件测试,覆盖登录、项目库、Dashboard、Canvas、工作区、模型状态、时间轴、本体和模板库。

- 新增 pytest 后端测试夹具和 auth/projects/templates/media/AI/export/dashboard/tasks/progress 测试,使用 SQLite、fake MinIO、fake SAM registry 和 Redis monkeypatch 隔离外部服务。

- 新增 doc/ 文档结构,冻结当前需求、设计、接口契约、测试计划、前端逐元素审计、实现地图和后续实施计划,并同步更新 README 与 AGENTS。

验证:

- conda run -n seg_server pytest backend/tests:27 passed。

- npm run test:run:54 passed。

- npm run lint、npm run build、compileall、git diff --check 均通过;Vite 仅提示大 chunk 警告。
2026-05-01 13:29:14 +08:00

298 lines
11 KiB
Python

"""SAM 2 engine wrapper with lazy loading and explicit runtime status."""
import logging
import os
from typing import Optional
import numpy as np
from config import settings
logger = logging.getLogger(__name__)
# ---------------------------------------------------------------------------
# Attempt to import PyTorch and SAM 2; fall back to stubs if unavailable.
# ---------------------------------------------------------------------------
try:
import torch
TORCH_AVAILABLE = True
except Exception as exc: # noqa: BLE001
TORCH_AVAILABLE = False
torch = None # type: ignore[assignment]
logger.warning("PyTorch import failed (%s). SAM2 will be unavailable.", exc)
try:
from sam2.build_sam import build_sam2
from sam2.sam2_image_predictor import SAM2ImagePredictor
SAM2_AVAILABLE = True
logger.info("SAM2 library imported successfully.")
except Exception as exc: # noqa: BLE001
SAM2_AVAILABLE = False
logger.warning("SAM2 import failed (%s). Using stub engine.", exc)
class SAM2Engine:
"""Lazy-loaded SAM 2 inference engine."""
def __init__(self) -> None:
self._predictor: Optional[SAM2ImagePredictor] = None
self._model_loaded = False
self._loaded_device: str | None = None
self._last_error: str | None = None
# -----------------------------------------------------------------------
# Internal helpers
# -----------------------------------------------------------------------
def _load_model(self) -> None:
"""Load the SAM 2 model and predictor on first use."""
if self._model_loaded:
return
if not TORCH_AVAILABLE:
self._last_error = "PyTorch is not installed."
logger.warning("PyTorch not available; skipping SAM2 model load.")
self._model_loaded = True
return
if not SAM2_AVAILABLE:
self._last_error = "sam2 package is not installed."
logger.warning("SAM2 not available; skipping model load.")
self._model_loaded = True
return
if not os.path.isfile(settings.sam_model_path):
self._last_error = f"SAM2 checkpoint not found: {settings.sam_model_path}"
logger.error("SAM checkpoint not found at %s", settings.sam_model_path)
self._model_loaded = True
return
try:
device = self._best_device()
model = build_sam2(
settings.sam_model_config,
settings.sam_model_path,
device=device,
)
self._predictor = SAM2ImagePredictor(model)
self._model_loaded = True
self._loaded_device = device
self._last_error = None
logger.info("SAM 2 model loaded from %s on %s", settings.sam_model_path, device)
except Exception as exc: # noqa: BLE001
self._last_error = str(exc)
logger.error("Failed to load SAM 2 model: %s", exc)
self._model_loaded = True # Prevent repeated load attempts
def _best_device(self) -> str:
if TORCH_AVAILABLE and torch is not None and torch.cuda.is_available():
return "cuda"
return "cpu"
def _ensure_ready(self) -> bool:
"""Ensure the model is loaded; return whether it is usable."""
self._load_model()
return SAM2_AVAILABLE and self._predictor is not None
def status(self) -> dict:
"""Return lightweight, real runtime status without forcing model load."""
checkpoint_exists = os.path.isfile(settings.sam_model_path)
device = self._loaded_device or self._best_device()
available = bool(TORCH_AVAILABLE and SAM2_AVAILABLE and checkpoint_exists)
if self._predictor is not None:
message = "SAM 2 model loaded and ready."
elif available:
message = "SAM 2 dependencies and checkpoint are present; model will load on first inference."
else:
missing = []
if not TORCH_AVAILABLE:
missing.append("PyTorch")
if not SAM2_AVAILABLE:
missing.append("sam2 package")
if not checkpoint_exists:
missing.append("checkpoint")
message = f"SAM 2 unavailable: missing {', '.join(missing)}."
if self._last_error and not self._predictor:
message = self._last_error
return {
"id": "sam2",
"label": "SAM 2",
"available": available,
"loaded": self._predictor is not None,
"device": device,
"supports": ["point", "box", "auto"],
"message": message,
"package_available": SAM2_AVAILABLE,
"checkpoint_exists": checkpoint_exists,
"checkpoint_path": settings.sam_model_path,
"python_ok": True,
"torch_ok": TORCH_AVAILABLE,
"cuda_required": False,
}
# -----------------------------------------------------------------------
# Public API
# -----------------------------------------------------------------------
def predict_points(
self,
image: np.ndarray,
points: list[list[float]],
labels: list[int],
) -> tuple[list[list[list[float]]], list[float]]:
"""Run point-prompt segmentation.
Args:
image: HWC numpy array (uint8).
points: List of [x, y] normalized coordinates (0-1).
labels: 1 for foreground, 0 for background.
Returns:
Tuple of (polygons, scores).
"""
if not self._ensure_ready():
logger.warning("SAM2 not ready; returning dummy masks.")
return self._dummy_polygons(image.shape[1], image.shape[0]), [0.5]
try:
h, w = image.shape[:2]
pts = np.array([[p[0] * w, p[1] * h] for p in points], dtype=np.float32)
lbls = np.array(labels, dtype=np.int32)
with torch.inference_mode(): # type: ignore[name-defined]
self._predictor.set_image(image)
masks, scores, _ = self._predictor.predict(
point_coords=pts,
point_labels=lbls,
multimask_output=True,
)
polygons = []
for m in masks:
poly = self._mask_to_polygon(m)
if poly:
polygons.append(poly)
return polygons, scores.tolist()
except Exception as exc: # noqa: BLE001
logger.error("SAM2 point prediction failed: %s", exc)
return self._dummy_polygons(image.shape[1], image.shape[0]), [0.5]
def predict_box(
self,
image: np.ndarray,
box: list[float],
) -> tuple[list[list[list[float]]], list[float]]:
"""Run box-prompt segmentation.
Args:
image: HWC numpy array (uint8).
box: [x1, y1, x2, y2] normalized coordinates.
Returns:
Tuple of (polygons, scores).
"""
if not self._ensure_ready():
logger.warning("SAM2 not ready; returning dummy masks.")
return self._dummy_polygons(image.shape[1], image.shape[0]), [0.5]
try:
h, w = image.shape[:2]
bbox = np.array(
[box[0] * w, box[1] * h, box[2] * w, box[3] * h],
dtype=np.float32,
)
with torch.inference_mode(): # type: ignore[name-defined]
self._predictor.set_image(image)
masks, scores, _ = self._predictor.predict(
box=bbox[None, :],
multimask_output=False,
)
polygons = []
for m in masks:
poly = self._mask_to_polygon(m)
if poly:
polygons.append(poly)
return polygons, scores.tolist()
except Exception as exc: # noqa: BLE001
logger.error("SAM2 box prediction failed: %s", exc)
return self._dummy_polygons(image.shape[1], image.shape[0]), [0.5]
def predict_auto(self, image: np.ndarray) -> tuple[list[list[list[float]]], list[float]]:
"""Run automatic mask generation (grid of points).
Args:
image: HWC numpy array (uint8).
Returns:
Tuple of (polygons, scores).
"""
if not self._ensure_ready():
logger.warning("SAM2 not ready; returning dummy masks.")
return self._dummy_polygons(image.shape[1], image.shape[0]), [0.5]
try:
with torch.inference_mode(): # type: ignore[name-defined]
self._predictor.set_image(image)
# Generate a uniform 16x16 grid of point prompts
h, w = image.shape[:2]
grid = np.mgrid[0:1:17j, 0:1:17j].reshape(2, -1).T
pts = grid * np.array([w, h])
lbls = np.ones(pts.shape[0], dtype=np.int32)
masks, scores, _ = self._predictor.predict(
point_coords=pts,
point_labels=lbls,
multimask_output=True,
)
polygons = []
for m in masks[:3]: # Limit to top 3 masks
poly = self._mask_to_polygon(m)
if poly:
polygons.append(poly)
return polygons, scores[:3].tolist()
except Exception as exc: # noqa: BLE001
logger.error("SAM2 auto prediction failed: %s", exc)
return self._dummy_polygons(image.shape[1], image.shape[0]), [0.5]
# -----------------------------------------------------------------------
# Helpers
# -----------------------------------------------------------------------
@staticmethod
def _mask_to_polygon(mask: np.ndarray) -> list[list[float]]:
"""Convert a binary mask to a normalized polygon."""
import cv2
if mask.dtype != np.uint8:
mask = (mask > 0).astype(np.uint8)
contours, _ = cv2.findContours(mask, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
h, w = mask.shape[:2]
largest = []
for cnt in contours:
if len(cnt) > len(largest):
largest = cnt
if len(largest) < 3:
return []
return [[float(pt[0][0]) / w, float(pt[0][1]) / h] for pt in largest]
@staticmethod
def _dummy_polygons(w: int, h: int) -> list[list[list[float]]]:
"""Return a dummy rectangle polygon for fallback mode."""
return [
[
[0.25, 0.25],
[0.75, 0.25],
[0.75, 0.75],
[0.25, 0.75],
]
]
# Singleton instance
sam_engine = SAM2Engine()