From c8930cc27964680b0df97aaed2250347c449ad07 Mon Sep 17 00:00:00 2001
From: Alexander Alekhin <alexander.a.alekhin@gmail.com>
Date: Sat, 27 Jan 2018 13:37:38 +0000
Subject: [PATCH] opencv_version: dump detected HW features

---
 apps/version/opencv_version.cpp               | 22 +++++++++++++++++++
 modules/core/include/opencv2/core/utility.hpp |  6 +++++
 modules/core/src/system.cpp                   |  5 +++++
 3 files changed, 33 insertions(+)

diff --git a/apps/version/opencv_version.cpp b/apps/version/opencv_version.cpp
index ecb602c171..04aa25917f 100644
--- a/apps/version/opencv_version.cpp
+++ b/apps/version/opencv_version.cpp
@@ -20,6 +20,7 @@ int main(int argc, const char** argv)
         "{ help h usage ? |      | show this help message }"
         "{ verbose v      |      | show build configuration log }"
         "{ opencl         |      | show information about OpenCL (available platforms/devices, default selected device) }"
+        "{ hw             |      | show detected HW features (see cv::checkHardwareSupport() function). Use --hw=0 to show available features only }"
     );
 
     if (parser.has("help"))
@@ -42,5 +43,26 @@ int main(int argc, const char** argv)
         cv::dumpOpenCLInformation();
     }
 
+    if (parser.has("hw"))
+    {
+        bool showAll = parser.get<bool>("hw");
+        std::cout << "OpenCV's HW features list:" << std::endl;
+        int count = 0;
+        for (int i = 0; i < CV_HARDWARE_MAX_FEATURE; i++)
+        {
+            cv::String name = cv::getHardwareFeatureName(i);
+            if (name.empty())
+                continue;
+            bool enabled = cv::checkHardwareSupport(i);
+            if (enabled)
+                count++;
+            if (enabled || showAll)
+            {
+                printf("    ID=%3d (%s) -> %s\n", i, name.c_str(), enabled ? "ON" : "N/A");
+            }
+        }
+        std::cout << "Total available: " << count << std::endl;
+    }
+
     return 0;
 }
diff --git a/modules/core/include/opencv2/core/utility.hpp b/modules/core/include/opencv2/core/utility.hpp
index 69d114e156..863012710c 100644
--- a/modules/core/include/opencv2/core/utility.hpp
+++ b/modules/core/include/opencv2/core/utility.hpp
@@ -427,6 +427,12 @@ in OpenCV.
  */
 CV_EXPORTS_W bool checkHardwareSupport(int feature);
 
+/** @brief Returns feature name by ID
+
+Returns empty string if feature is not defined
+*/
+CV_EXPORTS_W String getHardwareFeatureName(int feature);
+
 /** @brief Returns the number of logical CPUs available for the process.
  */
 CV_EXPORTS_W int getNumberOfCPUs();
diff --git a/modules/core/src/system.cpp b/modules/core/src/system.cpp
index ccf2ca0e28..ceca01f82e 100644
--- a/modules/core/src/system.cpp
+++ b/modules/core/src/system.cpp
@@ -663,6 +663,11 @@ bool checkHardwareSupport(int feature)
     return currentFeatures->have[feature];
 }
 
+String getHardwareFeatureName(int feature)
+{
+    const char* name = getHWFeatureName(feature);
+    return name ? String(name) : String();
+}
 
 volatile bool useOptimizedFlag = true;