| public Push ( Array value ) : void | ||
| value | Array | The value to be pushed to the vector |
| return | void | |
public static Matrix<byte> ExtractBriefFeatureDescriptors(Emgu.CV.Image<Gray, byte> im, MKeyPoint kp)
{
var f = new VectorOfKeyPoint();
f.Push(new MKeyPoint[] { kp });
//i'm are going to invoke this with a single point because otherwise I cannot tell which points failed to get descriptors
return new BriefDescriptorExtractor().ComputeDescriptorsRaw(im, (Emgu.CV.Image<Gray, byte>)null, f);
}
/// <summary>
/// Compute the descriptor given the image and the point location
/// </summary>
/// <param name="image">The image where the descriptor will be computed from</param>
/// <param name="mask">The optional mask, can be null if not needed</param>
/// <param name="keyPoints">The keypoint where the descriptor will be computed from</param>
/// <returns>The image features founded on the keypoint location</returns>
public ImageFeature[] ComputeDescriptors(Image<Gray, Byte> image, Image<Gray, byte> mask, MKeyPoint[] keyPoints)
{
using (VectorOfFloat descs = new VectorOfFloat())
using (VectorOfKeyPoint kpts = new VectorOfKeyPoint())
{
kpts.Push(keyPoints);
CvSURFDetectorComputeDescriptors(ref this, image, mask, kpts, descs);
int n = keyPoints.Length;
long address = descs.StartAddress.ToInt64();
ImageFeature[] features = new ImageFeature[n];
int sizeOfdescriptor = extended == 0 ? 64 : 128;
for (int i = 0; i < n; i++, address += sizeOfdescriptor * sizeof(float))
{
features[i].KeyPoint = keyPoints[i];
float[] desc = new float[sizeOfdescriptor];
Marshal.Copy(new IntPtr(address), desc, 0, sizeOfdescriptor);
features[i].Descriptor = desc;
}
return features;
}
}
/// <summary>
/// Compute the descriptor given the image and the point location
/// </summary>
/// <param name="image">The image where the descriptor will be computed from</param>
/// <param name="mask">The optional mask, can be null if not needed</param>
/// <param name="keyPoints">The keypoint where the descriptor will be computed from</param>
/// <returns>The image features founded on the keypoint location</returns>
public ImageFeature[] ComputeDescriptors(Image<Gray, Byte> image, Image<Gray, byte> mask, MKeyPoint[] keyPoints)
{
if (keyPoints.Length == 0) return new ImageFeature[0];
using (VectorOfFloat descVec = new VectorOfFloat())
using (VectorOfKeyPoint kpts = new VectorOfKeyPoint())
{
kpts.Push(keyPoints);
CvSIFTDetectorComputeDescriptors(_ptr, image, mask, kpts, descVec);
int n = keyPoints.Length;
float[] descs = descVec.ToArray();
//long address = descVec.StartAddress.ToInt64();
ImageFeature[] features = new ImageFeature[n];
int sizeOfdescriptor = DescriptorSize;
for (int i = 0; i < n; i++)
{
features[i].KeyPoint = keyPoints[i];
float[] d = new float[sizeOfdescriptor];
Array.Copy(descs, i * sizeOfdescriptor, d, 0, sizeOfdescriptor);
features[i].Descriptor = d;
}
return features;
}
}
/// <summary>
/// Convert the image features to keypoint vector and descriptor matrix
/// </summary>
private static void ConvertFromImageFeature(ImageFeature[] features, out VectorOfKeyPoint keyPoints, out Matrix<float> descriptors)
{
keyPoints = new VectorOfKeyPoint();
keyPoints.Push( Array.ConvertAll<ImageFeature, MKeyPoint>(features, delegate(ImageFeature feature) { return feature.KeyPoint; }));
descriptors = new Matrix<float>(features.Length, features[0].Descriptor.Length);
int descriptorLength = features[0].Descriptor.Length;
float[,] data = descriptors.Data;
for (int i = 0; i < features.Length; i++)
{
for (int j = 0; j < descriptorLength; j++)
data[i, j] = features[i].Descriptor[j];
}
}
/*
/// <summary>
/// Compute the descriptor given the bgr image and the point location, using oppponent color (CGIV 2008 "Color Descriptors for Object Category Recognition").
/// </summary>
/// <param name="image">The image where the descriptor will be computed from</param>
/// <param name="keyPoints">The keypoint where the descriptor will be computed from</param>
/// <returns>The descriptors founded on the keypoint location</returns>
public Matrix<float> ComputeDescriptorsRaw(Image<Bgr, Byte> image, VectorOfKeyPoint keyPoints)
{
int count = keyPoints.Size;
if (count == 0) return null;
Matrix<float> descriptors = new Matrix<float>(count, DescriptorSize * 3, 1);
CvSIFTDetectorComputeDescriptorsBGR(_ptr, image, keyPoints, descriptors);
return descriptors;
}*/
/// <summary>
/// Compute the descriptor given the image and the point location
/// </summary>
/// <param name="image">The image where the descriptor will be computed from</param>
/// <param name="mask">The optional mask, can be null if not needed</param>
/// <param name="keyPoints">The keypoint where the descriptor will be computed from</param>
/// <returns>The descriptors founded on the keypoint location</returns>
public ImageFeature[] ComputeDescriptors(Image<Gray, Byte> image, Image<Gray, byte> mask, MKeyPoint[] keyPoints)
{
if (keyPoints.Length == 0) return new ImageFeature[0];
using (VectorOfKeyPoint kpts = new VectorOfKeyPoint())
{
kpts.Push(keyPoints);
using (Matrix<float> descriptor = ComputeDescriptorsRaw(image, mask, kpts))
{
return Features2DTracker.ConvertToImageFeature(kpts, descriptor);
}
}
}
/// <summary>
/// Compute the descriptor given the image and the point location
/// </summary>
/// <param name="image">The image where the descriptor will be computed from</param>
/// <param name="mask">The optional mask, can be null if not needed</param>
/// <param name="keyPoints">The keypoint where the descriptor will be computed from</param>
/// <returns>The image features founded on the keypoint location</returns>
public ImageFeature[] ComputeDescriptors(Image<Gray, Byte> image, Image<Gray, byte> mask, MKeyPoint[] keyPoints)
{
int sizeOfdescriptor = _surfParams.Extended ? 128 : 64;
using (VectorOfKeyPoint pts = new VectorOfKeyPoint())
{
pts.Push(keyPoints);
using (Matrix<float> descriptors = ComputeDescriptorsRaw(image, mask, pts))
return Features2DTracker.ConvertToImageFeature(pts, descriptors);
}
}
public void TestVectorOfKeyPointSerialization()
{
using (VectorOfKeyPoint kpts = new VectorOfKeyPoint())
{
using (MemoryStream ms = new MemoryStream())
{
kpts.Push(new MKeyPoint[] { new MKeyPoint() });
System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
formatter = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
formatter.Serialize(ms, kpts);
Byte[] bytes = ms.GetBuffer();
using (MemoryStream ms2 = new MemoryStream(bytes))
{
Object o = formatter.Deserialize(ms2);
VectorOfKeyPoint kpts2 = (VectorOfKeyPoint) o;
}
}
}
}
