Table Of Contents

Previous topic

Exposure Compensation

Next topic

cuda. CUDA-accelerated Computer Vision

Image Blenders

detail::Blender

class detail::Blender

Base class for all blenders.

class CV_EXPORTS Blender
{
public:
    virtual ~Blender() {}

    enum { NO, FEATHER, MULTI_BAND };
    static Ptr<Blender> createDefault(int type, bool try_gpu = false);

    void prepare(const std::vector<Point> &corners, const std::vector<Size> &sizes);
    virtual void prepare(Rect dst_roi);
    virtual void feed(const Mat &img, const Mat &mask, Point tl);
    virtual void blend(Mat &dst, Mat &dst_mask);

protected:
    Mat dst_, dst_mask_;
    Rect dst_roi_;
};

detail::Blender::prepare

Prepares the blender for blending.

C++: void detail::Blender::prepare(const std::vector<Point>& corners, const std::vector<Size>& sizes)
Parameters:
  • corners – Source images top-left corners
  • sizes – Source image sizes

detail::Blender::feed

Processes the image.

C++: void detail::Blender::feed(InputArray img, InputArray mask, Point tl)
Parameters:
  • img – Source image
  • mask – Source image mask
  • tl – Source image top-left corners

detail::Blender::blend

Blends and returns the final pano.

C++: void detail::Blender::blend(InputOutputArray dst, InputOutputArray dst_mask)
Parameters:
  • dst – Final pano
  • dst_mask – Final pano mask

detail::FeatherBlender

class detail::FeatherBlender : public detail::Blender

Simple blender which mixes images at its borders.

class CV_EXPORTS FeatherBlender : public Blender
{
public:
    FeatherBlender(float sharpness = 0.02f) { setSharpness(sharpness); }

    float sharpness() const { return sharpness_; }
    void setSharpness(float val) { sharpness_ = val; }

    void prepare(Rect dst_roi);
    void feed(const Mat &img, const Mat &mask, Point tl);
    void blend(Mat &dst, Mat &dst_mask);

    // Creates weight maps for fixed set of source images by their masks and top-left corners.
    // Final image can be obtained by simple weighting of the source images.
    Rect createWeightMaps(const std::vector<Mat> &masks, const std::vector<Point> &corners,
                          std::vector<Mat> &weight_maps);

private:
    /* hidden */
};

See also

detail::Blender

detail::MultiBandBlender

class detail::MultiBandBlender : public detail::Blender

Blender which uses multi-band blending algorithm (see [BA83]).

class CV_EXPORTS MultiBandBlender : public Blender
{
public:
    MultiBandBlender(int try_gpu = false, int num_bands = 5);
    int numBands() const { return actual_num_bands_; }
    void setNumBands(int val) { actual_num_bands_ = val; }

    void prepare(Rect dst_roi);
    void feed(const Mat &img, const Mat &mask, Point tl);
    void blend(Mat &dst, Mat &dst_mask);

private:
    /* hidden */
};

See also

detail::Blender