add face feature extraction pipeline

network_camera_receiver/include/network_camera_receiver.h

@@ -13,6 +13,15 @@
 #include <thread>
 #include <mutex>
 #include <atomic>
+#include <chrono>
+#include <cstdint>
+
+struct NetworkFrame {
+    cv::Mat image;
+    std::uint64_t frame_id = 0;
+    std::chrono::steady_clock::time_point captured_at;
+    std::int64_t captured_at_unix_ms = 0;
+};
 
 class NetworkCameraReceiver {
 public:
@@ -27,6 +36,7 @@ public:
     void stop();
     // 取最新帧（深拷贝到 out）；自上次取帧后若无新帧则返回 false
     bool getLatestFrame(cv::Mat& out);
+    bool getLatestFrame(NetworkFrame& out);
     // 视频流是否已打开
     bool isOpened() const;
 
@@ -40,6 +50,9 @@ private:
     std::thread capture_thread;
     std::mutex mtx;                 // 保护 latest_frame
     cv::Mat latest_frame;           // 最新一帧
+    std::uint64_t latest_frame_id = 0;
+    std::chrono::steady_clock::time_point latest_captured_at;
+    std::int64_t latest_captured_at_unix_ms = 0;
     std::atomic<bool> has_new_frame{false};
     std::atomic<bool> running{false};
 };

network_camera_receiver/src/network_camera_receiver.cpp

@@ -57,17 +57,31 @@ void NetworkCameraReceiver::captureLoop() {
             std::lock_guard<std::mutex> lock(mtx);
             // 仅保留最新一帧，旧帧直接丢弃
             frame.copyTo(latest_frame);
+            ++latest_frame_id;
+            latest_captured_at = std::chrono::steady_clock::now();
+            latest_captured_at_unix_ms = std::chrono::duration_cast<std::chrono::milliseconds>(
+                std::chrono::system_clock::now().time_since_epoch()).count();
         }
         has_new_frame.store(true);
     }
 }
 
 bool NetworkCameraReceiver::getLatestFrame(cv::Mat& out) {
+    NetworkFrame frame;
+    if (!getLatestFrame(frame)) return false;
+    out = frame.image;
+    return true;
+}
+
+bool NetworkCameraReceiver::getLatestFrame(NetworkFrame& out) {
     if (!has_new_frame.load()) return false;
     // 先清标记：若在此期间后台又写入新帧，标记会被再次置 true，下一轮可取到
     has_new_frame.store(false);
     std::lock_guard<std::mutex> lock(mtx);
     if (latest_frame.empty()) return false;
-    latest_frame.copyTo(out);
+    latest_frame.copyTo(out.image);
+    out.frame_id = latest_frame_id;
+    out.captured_at = latest_captured_at;
+    out.captured_at_unix_ms = latest_captured_at_unix_ms;
     return true;
 }