diff --git a/mediapipe/tasks/c/components/containers/detection_result_converter_test.cc b/mediapipe/tasks/c/components/containers/detection_result_converter_test.cc
index 884481f29..2fd85bf31 100644
--- a/mediapipe/tasks/c/components/containers/detection_result_converter_test.cc
+++ b/mediapipe/tasks/c/components/containers/detection_result_converter_test.cc
@@ -25,4 +25,54 @@ limitations under the License.
 
 namespace mediapipe::tasks::c::components::containers {
 
+TEST(DetectionResultConverterTest, ConvertsDetectionResultCustomCategory) {
+  mediapipe::tasks::components::containers::DetectionResult
+      cpp_detection_result = {/* detections= */ {
+          {/* categories= */ {{/* index= */ 1, /* score= */ 0.1,
+                               /* category_name= */ "cat",
+                               /* display_name= */ "cat"}},
+           /* bounding_box= */ {10, 10, 10, 10},
+           {/* keypoints */ {{0.1, 0.1, "foo", 0.5}}}}}};
+
+  DetectionResult c_detection_result;
+  CppConvertToDetectionResult(cpp_detection_result, &c_detection_result);
+  EXPECT_NE(c_detection_result.detections, nullptr);
+  EXPECT_EQ(c_detection_result.detections_count, 1);
+  EXPECT_NE(c_detection_result.detections[0].categories, nullptr);
+  EXPECT_EQ(c_detection_result.detections[0].categories_count, 1);
+  EXPECT_EQ(c_detection_result.detections[0].bounding_box.left, 10);
+  EXPECT_EQ(c_detection_result.detections[0].bounding_box.top, 10);
+  EXPECT_EQ(c_detection_result.detections[0].bounding_box.right, 10);
+  EXPECT_EQ(c_detection_result.detections[0].bounding_box.bottom, 10);
+  EXPECT_NE(c_detection_result.detections[0].keypoints, nullptr);
+
+  CppCloseDetectionResult(&c_detection_result);
+}
+
+TEST(DetectionResultConverterTest, ConvertsDetectionResultNoCategory) {
+  mediapipe::tasks::components::containers::DetectionResult
+      cpp_detection_result = {/* detections= */ {/* categories= */ {}}};
+
+  DetectionResult c_detection_result;
+  CppConvertToDetectionResult(cpp_detection_result, &c_detection_result);
+  EXPECT_NE(c_detection_result.detections, nullptr);
+  EXPECT_EQ(c_detection_result.detections_count, 1);
+  EXPECT_NE(c_detection_result.detections[0].categories, nullptr);
+  EXPECT_EQ(c_detection_result.detections[0].categories_count, 0);
+
+  CppCloseDetectionResult(&c_detection_result);
+}
+
+TEST(DetectionResultConverterTest, FreesMemory) {
+  mediapipe::tasks::components::containers::DetectionResult
+      cpp_detection_result = {/* detections= */ {{/* categories= */ {}}}};
+
+  DetectionResult c_detection_result;
+  CppConvertToDetectionResult(cpp_detection_result, &c_detection_result);
+  EXPECT_NE(c_detection_result.detections, nullptr);
+
+  CppCloseDetectionResult(&c_detection_result);
+  EXPECT_EQ(c_detection_result.detections, nullptr);
+}
+
 }  // namespace mediapipe::tasks::c::components::containers
diff --git a/mediapipe/tasks/c/components/containers/keypoint_converter.cc b/mediapipe/tasks/c/components/containers/keypoint_converter.cc
index 53e8a5da1..2d64e8063 100644
--- a/mediapipe/tasks/c/components/containers/keypoint_converter.cc
+++ b/mediapipe/tasks/c/components/containers/keypoint_converter.cc
@@ -15,7 +15,6 @@ limitations under the License.
 
 #include "mediapipe/tasks/c/components/containers/keypoint_converter.h"
 
-#include <cstdint>
 #include <cstdlib>
 #include <cstring>
 
@@ -38,7 +37,7 @@ void CppConvertToNormalizedKeypoint(
 void CppCloseNormalizedKeypoint(NormalizedKeypoint* keypoint) {
   if (keypoint && keypoint->label) {
     free(keypoint->label);
-    keypoint->label = NULL;
+    keypoint->label = nullptr;
   }
 }
 
diff --git a/mediapipe/tasks/c/components/containers/keypoint_converter_test.cc b/mediapipe/tasks/c/components/containers/keypoint_converter_test.cc
index ca09154c3..38bf1e3c6 100644
--- a/mediapipe/tasks/c/components/containers/keypoint_converter_test.cc
+++ b/mediapipe/tasks/c/components/containers/keypoint_converter_test.cc
@@ -25,11 +25,29 @@ limitations under the License.
 
 namespace mediapipe::tasks::c::components::containers {
 
-TEST(RectConverterTest, ConvertsRectCustomValues) {
-  mediapipe::tasks::components::containers::Rect cpp_rect = {0, 0, 0, 0};
+constexpr float kPrecision = 1e-6;
 
-  Rect c_rect;
-  CppConvertToRect(cpp_rect, &c_rect);
+TEST(KeypointConverterTest, ConvertsKeypointCustomValues) {
+  mediapipe::tasks::components::containers::NormalizedKeypoint cpp_keypoint = {
+      0.1, 0.1, "foo", 0.5};
+
+  NormalizedKeypoint c_keypoint;
+  CppConvertToNormalizedKeypoint(cpp_keypoint, &c_keypoint);
+  EXPECT_NEAR(c_keypoint.x, 0.1f, kPrecision);
+  EXPECT_NEAR(c_keypoint.x, 0.1f, kPrecision);
+  EXPECT_EQ(std::string(c_keypoint.label), "foo");
+  EXPECT_NEAR(c_keypoint.score, 0.5f, kPrecision);
+}
+
+TEST(KeypointConverterTest, FreesMemory) {
+  mediapipe::tasks::components::containers::NormalizedKeypoint cpp_keypoint = {
+      0.1, 0.1, "foo", 0.5};
+
+  NormalizedKeypoint c_keypoint;
+  CppConvertToNormalizedKeypoint(cpp_keypoint, &c_keypoint);
+  EXPECT_NE(c_keypoint.label, nullptr);
+  CppCloseNormalizedKeypoint(&c_keypoint);
+  EXPECT_EQ(c_keypoint.label, nullptr);
 }
 
 }  // namespace mediapipe::tasks::c::components::containers
diff --git a/mediapipe/tasks/c/components/containers/rect_converter.cc b/mediapipe/tasks/c/components/containers/rect_converter.cc
index ff700acee..9f30bec4e 100644
--- a/mediapipe/tasks/c/components/containers/rect_converter.cc
+++ b/mediapipe/tasks/c/components/containers/rect_converter.cc
@@ -15,8 +15,6 @@ limitations under the License.
 
 #include "mediapipe/tasks/c/components/containers/rect_converter.h"
 
-#include <cstdlib>
-
 #include "mediapipe/tasks/c/components/containers/rect.h"
 #include "mediapipe/tasks/cc/components/containers/rect.h"
 
diff --git a/mediapipe/tasks/c/components/containers/rect_converter_test.cc b/mediapipe/tasks/c/components/containers/rect_converter_test.cc
index 3e8848094..eb2107240 100644
--- a/mediapipe/tasks/c/components/containers/rect_converter_test.cc
+++ b/mediapipe/tasks/c/components/containers/rect_converter_test.cc
@@ -41,7 +41,7 @@ TEST(RectFConverterTest, ConvertsRectFCustomValues) {
                                                               0.1};
 
   RectF c_rect;
-  CppConvertToRect(cpp_rect, &c_rect);
+  CppConvertToRectF(cpp_rect, &c_rect);
   EXPECT_FLOAT_EQ(c_rect.left, 0.1);
   EXPECT_FLOAT_EQ(c_rect.right, 0.1);
   EXPECT_FLOAT_EQ(c_rect.top, 0.1);