refactored features finders in stitching module

modules/stitching/include/opencv2/stitching/detail/matchers.hpp

@@ -46,6 +46,10 @@
 #include "opencv2/core/core.hpp"
 #include "opencv2/features2d/features2d.hpp"
 
+#ifndef ANDROID
+#include "opencv2/gpu/gpu.hpp"
+#endif
+
 namespace cv {
 namespace detail {
 
@@ -63,8 +67,6 @@ class CV_EXPORTS FeaturesFinder
 public:
     virtual ~FeaturesFinder() {}
     void operator ()(const Mat &image, ImageFeatures &features);
-
-    // TODO put it into operator ()
     virtual void collectGarbage() {}
 
 protected:
@@ -75,17 +77,38 @@ protected:
 class CV_EXPORTS SurfFeaturesFinder : public FeaturesFinder
 {
 public:
-    SurfFeaturesFinder(bool try_use_gpu = true, double hess_thresh = 300.0, 
-                       int num_octaves = 3, int num_layers = 4, 
+    SurfFeaturesFinder(double hess_thresh = 300., int num_octaves = 3, int num_layers = 4,
                        int num_octaves_descr = 4, int num_layers_descr = 2);
 
+private:
+    void find(const Mat &image, ImageFeatures &features);
+
+    Ptr<FeatureDetector> detector_;
+    Ptr<DescriptorExtractor> extractor_;
+};
+
+
+#ifndef ANDROID
+class SurfFeaturesFinderGpu : public FeaturesFinder
+{
+public:
+    SurfFeaturesFinderGpu(double hess_thresh = 300., int num_octaves = 3, int num_layers = 4,
+                          int num_octaves_descr = 4, int num_layers_descr = 2);
+
     void collectGarbage();
 
-protected:
+private:
     void find(const Mat &image, ImageFeatures &features);
 
-    Ptr<FeaturesFinder> impl_;
+    gpu::GpuMat image_;
+    gpu::GpuMat gray_image_;
+    gpu::SURF_GPU surf_;
+    gpu::GpuMat keypoints_;
+    gpu::GpuMat descriptors_;
+    int num_octaves_, num_layers_;
+    int num_octaves_descr_, num_layers_descr_;
 };
+#endif
 
 
 struct CV_EXPORTS MatchesInfo

modules/stitching/include/opencv2/stitching/warpers.hpp

@@ -77,7 +77,6 @@ public:
 
 
 #ifndef ANDROID
-
 class PlaneWarperGpu: public WarperCreator
 {
 public:
@@ -97,7 +96,6 @@ class SphericalWarperGpu: public WarperCreator
 public:
     Ptr<detail::Warper> createByFocalLength(double f) const { return new detail::SphericalWarperGpu(f); }
 };
-
 #endif
 
 } // namespace cv

modules/stitching/src/matchers.cpp

@@ -51,104 +51,6 @@ using namespace cv::gpu;
 
 namespace {
 
-class CpuSurfFeaturesFinder : public FeaturesFinder
-{
-public:
-    CpuSurfFeaturesFinder(double hess_thresh, int num_octaves, int num_layers,
-                          int num_octaves_descr, int num_layers_descr)
-    {
-        detector_ = new SurfFeatureDetector(hess_thresh, num_octaves, num_layers);
-        extractor_ = new SurfDescriptorExtractor(num_octaves_descr, num_layers_descr);
-    }
-
-protected:
-    void find(const Mat &image, ImageFeatures &features);
-
-private:
-    Ptr<FeatureDetector> detector_;
-    Ptr<DescriptorExtractor> extractor_;
-};
-
-#ifndef ANDROID
-class GpuSurfFeaturesFinder : public FeaturesFinder
-{
-public:
-    GpuSurfFeaturesFinder(double hess_thresh, int num_octaves, int num_layers,
-                          int num_octaves_descr, int num_layers_descr)
-    {
-        surf_.keypointsRatio = 0.1f;
-        surf_.hessianThreshold = hess_thresh;
-        surf_.extended = false;
-        num_octaves_ = num_octaves;
-        num_layers_ = num_layers;
-        num_octaves_descr_ = num_octaves_descr;
-        num_layers_descr_ = num_layers_descr;
-    }
-
-    void collectGarbage();
-
-protected:
-    void find(const Mat &image, ImageFeatures &features);
-
-private:
-    GpuMat image_;
-    GpuMat gray_image_;
-    SURF_GPU surf_;
-    GpuMat keypoints_;
-    GpuMat descriptors_;
-    int num_octaves_, num_layers_;
-    int num_octaves_descr_, num_layers_descr_;
-};
-#endif
-
-
-void CpuSurfFeaturesFinder::find(const Mat &image, ImageFeatures &features)
-{
-    Mat gray_image;
-    CV_Assert(image.depth() == CV_8U);
-    cvtColor(image, gray_image, CV_BGR2GRAY);
-    detector_->detect(gray_image, features.keypoints);
-    extractor_->compute(gray_image, features.keypoints, features.descriptors);
-}
-
-#ifndef ANDROID
-void GpuSurfFeaturesFinder::find(const Mat &image, ImageFeatures &features)
-{
-    CV_Assert(image.depth() == CV_8U);
-
-    ensureSizeIsEnough(image.size(), image.type(), image_);
-    image_.upload(image);
-
-    ensureSizeIsEnough(image.size(), CV_8UC1, gray_image_);
-    cvtColor(image_, gray_image_, CV_BGR2GRAY);
-
-    surf_.nOctaves = num_octaves_;
-    surf_.nOctaveLayers = num_layers_;
-    surf_.upright = false;
-    surf_(gray_image_, GpuMat(), keypoints_);
-
-    surf_.nOctaves = num_octaves_descr_;
-    surf_.nOctaveLayers = num_layers_descr_;
-    surf_.upright = true;
-    surf_(gray_image_, GpuMat(), keypoints_, descriptors_, true);
-    surf_.downloadKeypoints(keypoints_, features.keypoints);
-
-    descriptors_.download(features.descriptors);
-}
-
-void GpuSurfFeaturesFinder::collectGarbage()
-{
-    surf_.releaseMemory();
-    image_.release();
-    gray_image_.release();
-    keypoints_.release();
-    descriptors_.release();
-}
-#endif
-
-
-//////////////////////////////////////////////////////////////////////////////
-
 struct DistIdxPair
 {
     bool operator<(const DistIdxPair &other) const { return dist < other.dist; }
@@ -347,34 +249,76 @@ void FeaturesFinder::operator ()(const Mat &image, ImageFeatures &features)
 { 
     find(image, features);
     features.img_size = image.size();
-    //features.img = image.clone();
 }
 
 
-SurfFeaturesFinder::SurfFeaturesFinder(bool try_use_gpu, double hess_thresh, int num_octaves, int num_layers,
+SurfFeaturesFinder::SurfFeaturesFinder(double hess_thresh, int num_octaves, int num_layers,
                                        int num_octaves_descr, int num_layers_descr)
 {
-#ifndef ANDROID
-    if (try_use_gpu && getCudaEnabledDeviceCount() > 0)
-        impl_ = new GpuSurfFeaturesFinder(hess_thresh, num_octaves, num_layers, num_octaves_descr, num_layers_descr);
-    else
-#endif
-        impl_ = new CpuSurfFeaturesFinder(hess_thresh, num_octaves, num_layers, num_octaves_descr, num_layers_descr);
+    detector_ = new SurfFeatureDetector(hess_thresh, num_octaves, num_layers);
+    extractor_ = new SurfDescriptorExtractor(num_octaves_descr, num_layers_descr);
 }
 
 
 void SurfFeaturesFinder::find(const Mat &image, ImageFeatures &features)
 {
-    (*impl_)(image, features);
+    Mat gray_image;
+    CV_Assert(image.depth() == CV_8U);
+    cvtColor(image, gray_image, CV_BGR2GRAY);
+    detector_->detect(gray_image, features.keypoints);
+    extractor_->compute(gray_image, features.keypoints, features.descriptors);
 }
 
 
-void SurfFeaturesFinder::collectGarbage()
+#ifndef ANDROID
+SurfFeaturesFinderGpu::SurfFeaturesFinderGpu(double hess_thresh, int num_octaves, int num_layers,
+                                             int num_octaves_descr, int num_layers_descr)
 {
-    impl_->collectGarbage();
+    surf_.keypointsRatio = 0.1f;
+    surf_.hessianThreshold = hess_thresh;
+    surf_.extended = false;
+    num_octaves_ = num_octaves;
+    num_layers_ = num_layers;
+    num_octaves_descr_ = num_octaves_descr;
+    num_layers_descr_ = num_layers_descr;
 }
 
 
+void SurfFeaturesFinderGpu::find(const Mat &image, ImageFeatures &features)
+{
+    CV_Assert(image.depth() == CV_8U);
+
+    ensureSizeIsEnough(image.size(), image.type(), image_);
+    image_.upload(image);
+
+    ensureSizeIsEnough(image.size(), CV_8UC1, gray_image_);
+    cvtColor(image_, gray_image_, CV_BGR2GRAY);
+
+    surf_.nOctaves = num_octaves_;
+    surf_.nOctaveLayers = num_layers_;
+    surf_.upright = false;
+    surf_(gray_image_, GpuMat(), keypoints_);
+
+    surf_.nOctaves = num_octaves_descr_;
+    surf_.nOctaveLayers = num_layers_descr_;
+    surf_.upright = true;
+    surf_(gray_image_, GpuMat(), keypoints_, descriptors_, true);
+    surf_.downloadKeypoints(keypoints_, features.keypoints);
+
+    descriptors_.download(features.descriptors);
+}
+
+void SurfFeaturesFinderGpu::collectGarbage()
+{
+    surf_.releaseMemory();
+    image_.release();
+    gray_image_.release();
+    keypoints_.release();
+    descriptors_.release();
+}
+#endif
+
+
 //////////////////////////////////////////////////////////////////////////////
 
 MatchesInfo::MatchesInfo() : src_img_idx(-1), dst_img_idx(-1), num_inliers(0), confidence(0) {}

modules/stitching/src/stitcher.cpp

@@ -46,7 +46,6 @@ using namespace std;
 
 namespace cv {
 
-// TODO put all #ifndef ANDROID here, avoid passing try_use_gpu
 Stitcher Stitcher::createDefault(bool try_use_gpu)
 {
     Stitcher stitcher;
@@ -55,18 +54,25 @@ Stitcher Stitcher::createDefault(bool try_use_gpu)
     stitcher.setCompositingResol(ORIG_RESOL);
     stitcher.setPanoConfidenceThresh(1);
     stitcher.setHorizontalStrightening(true);
-    stitcher.setFeaturesFinder(new detail::SurfFeaturesFinder(try_use_gpu));
     stitcher.setFeaturesMatcher(new detail::BestOf2NearestMatcher(try_use_gpu));
+
 #ifndef ANDROID
-    bool must_use_gpu = try_use_gpu && (gpu::getCudaEnabledDeviceCount() > 0);
-    stitcher.setWarper(must_use_gpu ? static_cast<WarperCreator*>(new SphericalWarperGpu()) :
-                                      static_cast<WarperCreator*>(new SphericalWarper()));
-#else
-    stitcher.setWarper(new SphericalWarper());
+    if (try_use_gpu && gpu::getCudaEnabledDeviceCount() > 0)
+    {
+        stitcher.setFeaturesFinder(new detail::SurfFeaturesFinderGpu());
+        stitcher.setWarper(new SphericalWarperGpu());
+    }
+    else
 #endif
+    {
+        stitcher.setFeaturesFinder(new detail::SurfFeaturesFinder());
+        stitcher.setWarper(new SphericalWarper());
+    }
+
     stitcher.setExposureCompenstor(new detail::BlocksGainCompensator());
     stitcher.setSeamFinder(new detail::GraphCutSeamFinder());
     stitcher.setBlender(new detail::MultiBandBlender(try_use_gpu));
+
     return stitcher;
 }
 

samples/cpp/stitching_detailed.cpp

@@ -326,10 +326,16 @@ int main(int argc, char* argv[])
     LOGLN("Finding features...");
     int64 t = getTickCount();
 
-    vector<ImageFeatures> features(num_images);
-    SurfFeaturesFinder finder(try_gpu);
-    Mat full_img, img;
+    Ptr<FeaturesFinder> finder;
+#ifndef ANDROID
+    if (try_gpu && gpu::getCudaEnabledDeviceCount() > 0)
+        finder = new SurfFeaturesFinderGpu();
+    else
+#endif
+        finder = new SurfFeaturesFinder();
 
+    Mat full_img, img;
+    vector<ImageFeatures> features(num_images);
     vector<Mat> images(num_images);
     vector<Size> full_img_sizes(num_images);
     double seam_work_aspect = 1;
@@ -366,7 +372,7 @@ int main(int argc, char* argv[])
             is_seam_scale_set = true;
         }
 
-        finder(img, features[i]);
+        (*finder)(img, features[i]);
         features[i].img_idx = i;
         LOGLN("Features in image #" << i+1 << ": " << features[i].keypoints.size());
 
@@ -374,8 +380,7 @@ int main(int argc, char* argv[])
         images[i] = img.clone();
     }
 
-    finder.collectGarbage();
-
+    finder->collectGarbage();
     full_img.release();
     img.release();