Project import generated by Copybara.

GitOrigin-RevId: 5b23708185311ae39a8605b0c2eff721e7b4939f

mediapipe/calculators/video/BUILD

@@ -316,6 +316,7 @@ cc_library(
         "//mediapipe/util/tracking",
         "//mediapipe/util/tracking:box_tracker",
         "//mediapipe/util/tracking:tracking_visualization_utilities",
+        "@com_google_absl//absl/container:flat_hash_set",
         "@com_google_absl//absl/container:node_hash_set",
         "@com_google_absl//absl/strings",
     ],

mediapipe/calculators/video/box_tracker_calculator.cc

@@ -18,6 +18,7 @@
 #include <unordered_map>
 #include <unordered_set>
 
+#include "absl/container/flat_hash_set.h"
 #include "absl/container/node_hash_set.h"
 #include "absl/strings/numbers.h"
 #include "mediapipe/calculators/video/box_tracker_calculator.pb.h"
@@ -238,6 +239,11 @@ class BoxTrackerCalculator : public CalculatorBase {
   // Queued track time requests.
   std::vector<Timestamp> queued_track_requests_;
 
+  // Stores the tracked ids that have been discarded actively, from continuous
+  // tracking data. It may accumulate across multiple frames. Once consumed, it
+  // should be cleared immediately.
+  absl::flat_hash_set<int> actively_discarded_tracked_ids_;
+
   // Add smooth transition between re-acquisition and previous tracked boxes.
   // `result_box` is the tracking result of one specific timestamp. The smoothed
   // result will be updated in place.
@@ -1144,9 +1150,16 @@ void BoxTrackerCalculator::StreamTrack(const TrackingData& data,
   CHECK(box_map);
   CHECK(failed_ids);
 
+  // Cache the actively discarded tracked ids from the new tracking data.
+  for (const int discarded_id :
+       data.motion_data().actively_discarded_tracked_ids()) {
+    actively_discarded_tracked_ids_.insert(discarded_id);
+  }
+
   // Track all existing boxes by one frame.
   MotionVectorFrame mvf;  // Holds motion from current to previous frame.
   MotionVectorFrameFromTrackingData(data, &mvf);
+  mvf.actively_discarded_tracked_ids = &actively_discarded_tracked_ids_;
 
   if (forward) {
     MotionVectorFrame mvf_inverted;