diff --git a/plugins/logic_gate/color_analyzer.cpp b/plugins/logic_gate/color_analyzer.cpp
index 2532b3a..2551e4f 100644
--- a/plugins/logic_gate/color_analyzer.cpp
+++ b/plugins/logic_gate/color_analyzer.cpp
@@ -33,10 +33,12 @@ ColorResult ColorAnalyzer::Analyze(const Frame& frame, const Rect& bbox) {
         return result;
     }
 
-    const int sample_w = crop_w;
-    const int sample_h = std::max(1, crop_h / 3);
-    const int sample_x = 0;
-    const int sample_y = std::max(0, crop_h - sample_h);
+    // Sample the middle-lower shoe surface to avoid both bright trouser fabric
+    // above and reflective floor pixels near the sole.
+    const int sample_w = std::max(1, static_cast<int>(crop_w * 0.6f));
+    const int sample_h = std::max(1, static_cast<int>(crop_h * 0.4f));
+    const int sample_x = std::max(0, (crop_w - sample_w) / 2);
+    const int sample_y = std::max(0, static_cast<int>(crop_h * 0.35f));
 
     std::vector<uint8_t> sample(sample_w * sample_h * 3);
     for (int row = 0; row < sample_h; ++row) {
diff --git a/tests/test_color_analyzer.cpp b/tests/test_color_analyzer.cpp
index 541e7f3..7f0677b 100644
--- a/tests/test_color_analyzer.cpp
+++ b/tests/test_color_analyzer.cpp
@@ -10,10 +10,15 @@
 namespace rk3588 {
 namespace {
 
-Frame MakeRgbFrame(int width, int height, uint8_t top_value, uint8_t bottom_value) {
+Frame MakeRgbFrame(int width, int height, uint8_t top_value, uint8_t middle_value, uint8_t bottom_value) {
     auto pixels = std::make_shared<std::vector<uint8_t>>(static_cast<size_t>(width * height * 3), 0);
     for (int y = 0; y < height; ++y) {
-        const uint8_t value = (y < (height * 2 / 3)) ? top_value : bottom_value;
+        uint8_t value = bottom_value;
+        if (y < (height * 35 / 100)) {
+            value = top_value;
+        } else if (y < (height * 75 / 100)) {
+            value = middle_value;
+        }
         for (int x = 0; x < width; ++x) {
             const size_t idx = static_cast<size_t>((y * width + x) * 3);
             (*pixels)[idx] = value;
@@ -33,7 +38,7 @@ Frame MakeRgbFrame(int width, int height, uint8_t top_value, uint8_t bottom_valu
     return frame;
 }
 
-TEST(ColorAnalyzerTest, UsesBottomThirdInsteadOfCenterRegionForBrightness) {
+TEST(ColorAnalyzerTest, UsesMiddleLowerRegionForBrightness) {
     ColorConfig config;
     config.method = ColorMethod::RGB;
     config.dark_threshold = 80;
@@ -41,8 +46,8 @@ TEST(ColorAnalyzerTest, UsesBottomThirdInsteadOfCenterRegionForBrightness) {
     config.debug_output = false;
 
     ColorAnalyzer analyzer(config);
-    Frame frame = MakeRgbFrame(9, 9, 180, 20);
-    Rect bbox{0.0f, 0.0f, 9.0f, 9.0f};
+    Frame frame = MakeRgbFrame(10, 10, 180, 20, 200);
+    Rect bbox{0.0f, 0.0f, 10.0f, 10.0f};
 
     const ColorResult result = analyzer.Analyze(frame, bbox);