VideoCapture with digital camera and gPhoto2 library

CMakeLists.txt

@@ -205,6 +205,7 @@ OCV_OPTION(WITH_DIRECTX        "Include DirectX support"                     ON
 OCV_OPTION(WITH_INTELPERC      "Include Intel Perceptual Computing support"  OFF  IF (WIN32 AND NOT WINRT) )
 OCV_OPTION(WITH_IPP_A          "Include Intel IPP_A support"                 OFF  IF (MSVC OR X86 OR X86_64) )
 OCV_OPTION(WITH_GDAL           "Include GDAL Support"                        OFF  IF (NOT ANDROID AND NOT IOS AND NOT WINRT) )
+OCV_OPTION(WITH_GPHOTO2        "Include gPhoto2 library support"             ON   IF (UNIX AND NOT ANDROID) )
 
 # OpenCV build components
 # ===================================================
@@ -1032,6 +1033,10 @@ if(DEFINED WITH_INTELPERC)
   status("    Intel PerC:"     HAVE_INTELPERC      THEN "YES"                                 ELSE NO)
 endif(DEFINED WITH_INTELPERC)
 
+if(DEFINED WITH_GPHOTO2)
+  status("    gPhoto2:"        HAVE_GPHOTO2        THEN "YES"                                 ELSE NO)
+endif(DEFINED WITH_GPHOTO2)
+
 
 # ========================== Other third-party libraries ==========================
 status("")

cmake/OpenCVFindLibsVideo.cmake

@@ -311,3 +311,9 @@ endif()
 if(WITH_INTELPERC)
   include("${OpenCV_SOURCE_DIR}/cmake/OpenCVFindIntelPerCSDK.cmake")
 endif(WITH_INTELPERC)
+
+# --- gPhoto2 ---
+ocv_clear_vars(HAVE_GPHOTO2)
+if(WITH_GPHOTO2)
+  CHECK_MODULE(libgphoto2 HAVE_GPHOTO2)
+endif(WITH_GPHOTO2)

cmake/templates/cvconfig.h.in

@@ -178,3 +178,6 @@
 /* Define if your processor stores words with the most significant byte
    first (like Motorola and SPARC, unlike Intel and VAX). */
 #cmakedefine WORDS_BIGENDIAN
+
+/* gPhoto2 library */
+#cmakedefine HAVE_GPHOTO2

modules/videoio/CMakeLists.txt

@@ -186,6 +186,10 @@ if(HAVE_INTELPERC)
   list(APPEND VIDEOIO_LIBRARIES ${INTELPERC_LIBRARIES})
 endif(HAVE_INTELPERC)
 
+if(HAVE_GPHOTO2)
+  list(APPEND videoio_srcs ${CMAKE_CURRENT_LIST_DIR}/src/cap_gphoto2.cpp)
+endif(HAVE_GPHOTO2)
+
 if(IOS)
   add_definitions(-DHAVE_IOS=1)
   list(APPEND videoio_srcs

modules/videoio/include/opencv2/videoio.hpp

@@ -89,7 +89,8 @@ enum { CAP_ANY          = 0,     // autodetect
        CAP_WINRT        = 1410,  // Microsoft Windows Runtime using Media Foundation
        CAP_INTELPERC    = 1500,  // Intel Perceptual Computing SDK
        CAP_OPENNI2      = 1600,  // OpenNI2 (for Kinect)
-       CAP_OPENNI2_ASUS = 1610   // OpenNI2 (for Asus Xtion and Occipital Structure sensors)
+       CAP_OPENNI2_ASUS = 1610,  // OpenNI2 (for Asus Xtion and Occipital Structure sensors)
+       CAP_GPHOTO2      = 1700   // gPhoto2 connection
      };
 
 // generic properties (based on DC1394 properties)
@@ -382,6 +383,23 @@ enum { VIDEOWRITER_PROP_QUALITY = 1,    // Quality (0..100%) of the videostream
        VIDEOWRITER_PROP_FRAMEBYTES = 2, // (Read-only): Size of just encoded video frame
      };
 
+// gPhoto2 properties, if propertyId is less than 0 then work on widget with that __additive inversed__ camera setting ID
+// Get IDs by using CAP_PROP_GPHOTO2_WIDGET_ENUMERATE.
+// @see CvCaptureCAM_GPHOTO2 for more info
+enum { CAP_PROP_GPHOTO2_PREVIEW           = 17001, // Capture only preview from liveview mode.
+       CAP_PROP_GPHOTO2_WIDGET_ENUMERATE  = 17002, // Readonly, returns (const char *).
+       CAP_PROP_GPHOTO2_RELOAD_CONFIG     = 17003, // Trigger, only by set. Reload camera settings.
+       CAP_PROP_GPHOTO2_RELOAD_ON_CHANGE  = 17004, // Reload all settings on set.
+       CAP_PROP_GPHOTO2_COLLECT_MSGS      = 17005, // Collect messages with details.
+       CAP_PROP_GPHOTO2_FLUSH_MSGS        = 17006, // Readonly, returns (const char *).
+       CAP_PROP_SPEED                     = 17007, // Exposure speed. Can be readonly, depends on camera program.
+       CAP_PROP_APERTURE                  = 17008, // Aperture. Can be readonly, depends on camera program.
+       CAP_PROP_EXPOSUREPROGRAM           = 17009, // Camera exposure program.
+       CAP_PROP_VIEWFINDER                = 17010  // Enter liveview mode.
+     };
+
+//enum {
+
 class IVideoCapture;
 
 /** @brief Class for video capturing from video files, image sequences or cameras. The class provides C++ API

modules/videoio/include/opencv2/videoio/videoio_c.h

@@ -110,7 +110,9 @@ enum
 
     CV_CAP_INTELPERC = 1500, // Intel Perceptual Computing
 
-    CV_CAP_OPENNI2 = 1600   // OpenNI2 (for Kinect)
+    CV_CAP_OPENNI2 = 1600,   // OpenNI2 (for Kinect)
+
+    CV_CAP_GPHOTO2 = 1700
 };
 
 /* start capturing frames from camera: index = camera_index + domain_offset (CV_CAP_*) */
@@ -391,6 +393,23 @@ enum
     CV_CAP_INTELPERC_IMAGE                  = 3
 };
 
+// gPhoto2 properties, if propertyId is less than 0 then work on widget with that __additive inversed__ camera setting ID
+// Get IDs by using CAP_PROP_GPHOTO2_WIDGET_ENUMERATE.
+// @see CvCaptureCAM_GPHOTO2 for more info
+enum
+{
+    CV_CAP_PROP_GPHOTO2_PREVIEW           = 17001, // Capture only preview from liveview mode.
+    CV_CAP_PROP_GPHOTO2_WIDGET_ENUMERATE  = 17002, // Readonly, returns (const char *).
+    CV_CAP_PROP_GPHOTO2_RELOAD_CONFIG     = 17003, // Trigger, only by set. Reload camera settings.
+    CV_CAP_PROP_GPHOTO2_RELOAD_ON_CHANGE  = 17004, // Reload all settings on set.
+    CV_CAP_PROP_GPHOTO2_COLLECT_MSGS      = 17005, // Collect messages with details.
+    CV_CAP_PROP_GPHOTO2_FLUSH_MSGS        = 17006, // Readonly, returns (const char *).
+    CV_CAP_PROP_SPEED                     = 17007, // Exposure speed. Can be readonly, depends on camera program.
+    CV_CAP_PROP_APERTURE                  = 17008, // Aperture. Can be readonly, depends on camera program.
+    CV_CAP_PROP_EXPOSUREPROGRAM           = 17009, // Camera exposure program.
+    CV_CAP_PROP_VIEWFINDER                = 17010  // Enter liveview mode.
+};
+
 /* retrieve or set capture properties */
 CVAPI(double) cvGetCaptureProperty( CvCapture* capture, int property_id );
 CVAPI(int)    cvSetCaptureProperty( CvCapture* capture, int property_id, double value );

modules/videoio/src/cap.cpp

@@ -518,6 +518,9 @@ static Ptr<IVideoCapture> IVideoCapture_create(int index)
 #endif
 #ifdef WINRT_VIDEO
         CAP_WINRT,
+#endif
+#ifdef HAVE_GPHOTO2
+        CV_CAP_GPHOTO2,
 #endif
         -1, -1
     };
@@ -536,7 +539,8 @@ static Ptr<IVideoCapture> IVideoCapture_create(int index)
     {
 #if defined(HAVE_DSHOW)        || \
     defined(HAVE_INTELPERC)    || \
-    defined(WINRT_VIDEO)         || \
+    defined(WINRT_VIDEO)       || \
+    defined(HAVE_GPHOTO2)      || \
     (0)
         Ptr<IVideoCapture> capture;
 
@@ -558,6 +562,11 @@ static Ptr<IVideoCapture> IVideoCapture_create(int index)
             if (capture)
                 return capture;
             break; // CAP_WINRT
+#endif
+#ifdef HAVE_GPHOTO2
+            case CV_CAP_GPHOTO2:
+                capture = createGPhoto2Capture(index);
+                break;
 #endif
         }
         if (capture && capture->isOpened())
@@ -572,14 +581,37 @@ static Ptr<IVideoCapture> IVideoCapture_create(int index)
 
 static Ptr<IVideoCapture> IVideoCapture_create(const String& filename)
 {
-    Ptr<IVideoCapture> capture;
+    int  domains[] =
+    {
+        CV_CAP_ANY,
+#ifdef HAVE_GPHOTO2
+        CV_CAP_GPHOTO2,
+#endif
+        -1, -1
+    };
 
-    capture = createMotionJpegCapture(filename);
-    if (capture && capture->isOpened())
+    // try every possibly installed camera API
+    for (int i = 0; domains[i] >= 0; i++)
     {
-        return capture;
-    }
+        Ptr<IVideoCapture> capture;
+
+        switch (domains[i])
+        {
+        case CV_CAP_ANY:
+            capture = createMotionJpegCapture(filename);
+            break;
+#ifdef HAVE_GPHOTO2
+        case CV_CAP_GPHOTO2:
+            capture = createGPhoto2Capture(filename);
+            break;
+#endif
+        }
 
+        if (capture && capture->isOpened())
+        {
+            return capture;
+        }
+    }
     // failed open a camera
     return Ptr<IVideoCapture>();
 }
@@ -800,4 +832,4 @@ int VideoWriter::fourcc(char c1, char c2, char c3, char c4)
     return (c1 & 255) + ((c2 & 255) << 8) + ((c3 & 255) << 16) + ((c4 & 255) << 24);
 }
 
-}
\ No newline at end of file
+}

modules/videoio/src/precomp.hpp

@@ -186,6 +186,9 @@ namespace cv
 
     Ptr<IVideoCapture> createMotionJpegCapture(const String& filename);
     Ptr<IVideoWriter> createMotionJpegWriter( const String& filename, double fps, Size frameSize, bool iscolor );
+
+    Ptr<IVideoCapture> createGPhoto2Capture(int index);
+    Ptr<IVideoCapture> createGPhoto2Capture(const String& deviceName);
 };
 
 #endif /* __VIDEOIO_H_ */

modules/videoio/test/test_precomp.hpp

@@ -37,6 +37,7 @@
     defined(HAVE_AVFOUNDATION) || \
     defined(HAVE_GIGE_API)     || \
     defined(HAVE_INTELPERC)    || \
+    defined(HAVE_GPHOTO2)      || \
     (0)
     //defined(HAVE_ANDROID_NATIVE_CAMERA) ||   - enable after #1193
 #  define BUILD_WITH_CAMERA_SUPPORT 1