org.bytedeco.javacpp

Class opencv_core.SparseMat

java.lang.Object

org.bytedeco.javacpp.Pointer

org.bytedeco.javacpp.opencv_core.SparseMat

Enclosing class:

opencv_core

public static class opencv_core.SparseMat
extends Pointer

Sparse matrix class. The class represents multi-dimensional sparse numerical arrays. Such a sparse array can store elements of any type that cv::Mat is able to store. "Sparse" means that only non-zero elements are stored (though, as a result of some operations on a sparse matrix, some of its stored elements can actually become 0. It's user responsibility to detect such elements and delete them using cv::SparseMat::erase(). The non-zero elements are stored in a hash table that grows when it's filled enough, so that the search time remains O(1) in average. Elements can be accessed using the following methods:

1. Query operations: cv::SparseMat::ptr() and the higher-level cv::SparseMat::ref(), cv::SparseMat::value() and cv::SparseMat::find, for example: \code const int dims = 5; int size[] = {10, 10, 10, 10, 10}; SparseMat sparse_mat(dims, size, CV_32F); for(int i = 0; i < 1000; i++) { int idx[dims]; for(int k = 0; k < dims; k++) idx[k] = rand()%sparse_mat.size(k); sparse_mat.ref(idx) += 1.f; } \endcode
2. Sparse matrix iterators. Like cv::Mat iterators and unlike cv::Mat iterators, the sparse matrix iterators are STL-style, that is, the iteration is done as following: \code // prints elements of a sparse floating-point matrix and the sum of elements. SparseMatConstIterator_ it = sparse_mat.begin(), it_end = sparse_mat.end(); double s = 0; int dims = sparse_mat.dims(); for(; it != it_end; ++it) { // print element indices and the element value const Node* n = it.node(); printf("(") for(int i = 0; i < dims; i++) printf("%3d%c", n->idx[i], i < dims-1 ? ',' : ')'); printf(": %f\n", *it); s += *it; } printf("Element sum is %g\n", s); \endcode If you run this loop, you will notice that elements are enumerated in no any logical order (lexicographical etc.), they come in the same order as they stored in the hash table, i.e. semi-randomly. You may collect pointers to the nodes and sort them to get the proper ordering. Note, however, that pointers to the nodes may become invalid when you add more elements to the matrix; this is because of possible buffer reallocation.
3. A combination of the above 2 methods when you need to process 2 or more sparse matrices simultaneously, e.g. this is how you can compute unnormalized cross-correlation of the 2 floating-point sparse matrices: \code double crossCorr(const SparseMat& a, const SparseMat& b) { const SparseMat *_a = &a, *_b = &b; // if b contains less elements than a, // it's faster to iterate through b if(_a->nzcount() > _b->nzcount()) std::swap(_a, _b); SparseMatConstIterator_ it = _a->begin(), it_end = _a->end(); double ccorr = 0; for(; it != it_end; ++it) { // take the next element from the first matrix float avalue = *it; const Node* anode = it.node(); // and try to find element with the same index in the second matrix. // since the hash value depends only on the element index, // we reuse hashvalue stored in the node float bvalue = _b->value(anode->idx,&anode->hashval); ccorr += avalue*bvalue; } return ccorr; } \endcode

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	opencv_core.SparseMat.Hdr the sparse matrix header
static class	opencv_core.SparseMat.Node sparse matrix node - element of a hash table

Nested classes/interfaces inherited from class org.bytedeco.javacpp.Pointer

Pointer.CustomDeallocator, Pointer.Deallocator, Pointer.NativeDeallocator

Field Summary

Fields

Modifier and Type	Field and Description
static int	HASH_BIT enum cv::SparseMat::
static int	HASH_SCALE enum cv::SparseMat::
static int	MAGIC_VAL enum cv::SparseMat::
static int	MAX_DIM enum cv::SparseMat::

Fields inherited from class org.bytedeco.javacpp.Pointer

address, capacity, limit, position

Constructor Summary

Constructors

Constructor and Description
opencv_core.SparseMat() default constructor
opencv_core.SparseMat(int size)
opencv_core.SparseMat(int dims, int[] _sizes, int _type)
opencv_core.SparseMat(int dims, IntBuffer _sizes, int _type)
opencv_core.SparseMat(int dims, IntPointer _sizes, int _type) creates matrix of the specified size and type
opencv_core.SparseMat(opencv_core.CvSparseMat m) converts old-style sparse matrix to the new-style.
opencv_core.SparseMat(opencv_core.Mat m) converts dense 2d matrix to the sparse form /** \param m the input matrix
opencv_core.SparseMat(opencv_core.SparseMat m) copy constructor
opencv_core.SparseMat(Pointer p)

Method Summary

Methods

Modifier and Type	Method and Description
void	addref() manually increments the reference counter to the header.
opencv_core.CvSparseMat	asCvSparseMat() converts sparse matrix to the old-style representation; all the elements are copied.
void	assignTo(opencv_core.SparseMat m)
void	assignTo(opencv_core.SparseMat m, int type)
opencv_core.SparseMatIterator	begin() returns the sparse matrix iterator at the matrix beginning
int	channels() returns the number of channels
void	clear() sets all the sparse matrix elements to 0, which means clearing the hash table.
opencv_core.SparseMat	clone() creates full copy of the matrix
void	convertTo(opencv_core.Mat m, int rtype)
void	convertTo(opencv_core.Mat m, int rtype, double alpha, double beta) converts sparse matrix to dense n-dim matrix with optional type conversion and scaling.
void	convertTo(opencv_core.SparseMat m, int rtype)
void	convertTo(opencv_core.SparseMat m, int rtype, double alpha) multiplies all the matrix elements by the specified scale factor alpha and converts the results to the specified data type
void	copyTo(opencv_core.Mat m) converts sparse matrix to dense matrix.
void	copyTo(opencv_core.SparseMat m) copies all the data to the destination matrix.
void	create(int dims, int[] _sizes, int _type)
void	create(int dims, IntBuffer _sizes, int _type)
void	create(int dims, IntPointer _sizes, int _type) reallocates sparse matrix.
int	depth() returns the depth of sparse matrix elements
int	dims() returns the matrix dimensionality
long	elemSize() returns the size of each element in bytes (not including the overhead - the space occupied by SparseMat::Node elements)
long	elemSize1() returns elemSize()/channels()
opencv_core.SparseMatIterator	end() returns the sparse matrix iterator at the matrix end
void	erase(int[] idx)
void	erase(int[] idx, SizeTPointer hashval)
void	erase(IntBuffer idx)
void	erase(IntBuffer idx, SizeTPointer hashval)
void	erase(int i0, int i1)
void	erase(int i0, int i1, int i2)
void	erase(int i0, int i1, int i2, SizeTPointer hashval) erases the specified element (3D case)
void	erase(int i0, int i1, SizeTPointer hashval) erases the specified element (2D case)
void	erase(IntPointer idx)
void	erase(IntPointer idx, SizeTPointer hashval) erases the specified element (nD case)
int	flags()
opencv_core.SparseMat	flags(int flags)
long	hash(int i0) computes the element hash value (1D case)
long	hash(int[] idx)
long	hash(IntBuffer idx)
long	hash(int i0, int i1) computes the element hash value (2D case)
long	hash(int i0, int i1, int i2) computes the element hash value (3D case)
long	hash(IntPointer idx) computes the element hash value (nD case)
opencv_core.SparseMat.Hdr	hdr()
opencv_core.SparseMat	hdr(opencv_core.SparseMat.Hdr hdr)
byte[]	newNode(int[] idx, long hashval)
ByteBuffer	newNode(IntBuffer idx, long hashval)
BytePointer	newNode(IntPointer idx, long hashval)
opencv_core.SparseMat.Node	node(long nidx) returns the value stored in the sparse martix node
long	nzcount() returns the number of non-zero elements (=the number of hash table nodes)
opencv_core.SparseMat	position(int position)
byte[]	ptr(int[] idx, boolean createMissing)
byte[]	ptr(int[] idx, boolean createMissing, SizeTPointer hashval)
BytePointer	ptr(int i0, boolean createMissing)
BytePointer	ptr(int i0, boolean createMissing, SizeTPointer hashval) returns pointer to the specified element (1D case)
ByteBuffer	ptr(IntBuffer idx, boolean createMissing)
ByteBuffer	ptr(IntBuffer idx, boolean createMissing, SizeTPointer hashval)
BytePointer	ptr(int i0, int i1, boolean createMissing)
BytePointer	ptr(int i0, int i1, boolean createMissing, SizeTPointer hashval) returns pointer to the specified element (2D case)
BytePointer	ptr(int i0, int i1, int i2, boolean createMissing)
BytePointer	ptr(int i0, int i1, int i2, boolean createMissing, SizeTPointer hashval) returns pointer to the specified element (3D case)
BytePointer	ptr(IntPointer idx, boolean createMissing)
BytePointer	ptr(IntPointer idx, boolean createMissing, SizeTPointer hashval) returns pointer to the specified element (nD case)
opencv_core.SparseMat	put(opencv_core.Mat m) equivalent to the corresponding constructor
opencv_core.SparseMat	put(opencv_core.SparseMat m) assignment operator.
void	release()
void	removeNode(long hidx, long nidx, long previdx)
void	resizeHashTab(long newsize)
IntPointer	size() returns the array of sizes, or NULL if the matrix is not allocated
int	size(int i) returns the size of i-th matrix dimension (or 0)
int	type() returns type of sparse matrix elements

Methods inherited from class org.bytedeco.javacpp.Pointer

address, asBuffer, asByteBuffer, capacity, capacity, deallocate, deallocate, deallocateReferences, deallocator, deallocator, equals, fill, hashCode, isNull, limit, limit, memchr, memcmp, memcpy, memmove, memset, offsetof, position, put, setNull, sizeof, toString, withDeallocator, zero

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

MAGIC_VAL

public static final int MAGIC_VAL

enum cv::SparseMat::

See Also:

Constant Field Values

MAX_DIM

public static final int MAX_DIM

enum cv::SparseMat::

See Also:

Constant Field Values

HASH_SCALE

public static final int HASH_SCALE

enum cv::SparseMat::

See Also:

Constant Field Values

HASH_BIT

public static final int HASH_BIT

enum cv::SparseMat::

See Also:

Constant Field Values

Constructor Detail

opencv_core.SparseMat

public opencv_core.SparseMat(Pointer p)

opencv_core.SparseMat

public opencv_core.SparseMat(int size)

opencv_core.SparseMat

public opencv_core.SparseMat()

default constructor

opencv_core.SparseMat

public opencv_core.SparseMat(int dims,
                     IntPointer _sizes,
                     int _type)

creates matrix of the specified size and type

opencv_core.SparseMat

public opencv_core.SparseMat(int dims,
                     IntBuffer _sizes,
                     int _type)

opencv_core.SparseMat

public opencv_core.SparseMat(int dims,
                     int[] _sizes,
                     int _type)

opencv_core.SparseMat

public opencv_core.SparseMat(opencv_core.SparseMat m)

copy constructor

opencv_core.SparseMat

public opencv_core.SparseMat(opencv_core.Mat m)

converts dense 2d matrix to the sparse form /** \param m the input matrix

opencv_core.SparseMat

public opencv_core.SparseMat(opencv_core.CvSparseMat m)

converts old-style sparse matrix to the new-style. All the data is copied

Method Detail

position

public opencv_core.SparseMat position(int position)

Overrides:

position in class Pointer

put

public opencv_core.SparseMat put(opencv_core.SparseMat m)

assignment operator. This is O(1) operation, i.e. no data is copied

put

public opencv_core.SparseMat put(opencv_core.Mat m)

equivalent to the corresponding constructor

clone

public opencv_core.SparseMat clone()

creates full copy of the matrix

Overrides:

clone in class Object

copyTo

public void copyTo(opencv_core.SparseMat m)

copies all the data to the destination matrix. All the previous content of m is erased

copyTo

public void copyTo(opencv_core.Mat m)

converts sparse matrix to dense matrix.

convertTo

public void convertTo(opencv_core.SparseMat m,
             int rtype,
             double alpha)

multiplies all the matrix elements by the specified scale factor alpha and converts the results to the specified data type

convertTo

public void convertTo(opencv_core.SparseMat m,
             int rtype)

convertTo

public void convertTo(opencv_core.Mat m,
             int rtype,
             double alpha,
             double beta)

converts sparse matrix to dense n-dim matrix with optional type conversion and scaling. /** \param rtype The output matrix data type. When it is =-1, the output array will have the same data type as (*this) \param alpha The scale factor \param beta The optional delta added to the scaled values before the conversion

convertTo

public void convertTo(opencv_core.Mat m,
             int rtype)

assignTo

public void assignTo(opencv_core.SparseMat m,
            int type)

assignTo

public void assignTo(opencv_core.SparseMat m)

create

public void create(int dims,
          IntPointer _sizes,
          int _type)

reallocates sparse matrix. /** If the matrix already had the proper size and type, it is simply cleared with clear(), otherwise, the old matrix is released (using release()) and the new one is allocated.

create

public void create(int dims,
          IntBuffer _sizes,
          int _type)

create

public void create(int dims,
          int[] _sizes,
          int _type)

clear

public void clear()

sets all the sparse matrix elements to 0, which means clearing the hash table.

addref

public void addref()

manually increments the reference counter to the header.

release

public void release()

asCvSparseMat

public opencv_core.CvSparseMat asCvSparseMat()

converts sparse matrix to the old-style representation; all the elements are copied.

elemSize

public long elemSize()

returns the size of each element in bytes (not including the overhead - the space occupied by SparseMat::Node elements)

elemSize1

public long elemSize1()

returns elemSize()/channels()

type

public int type()

returns type of sparse matrix elements

depth

public int depth()

returns the depth of sparse matrix elements

channels

public int channels()

returns the number of channels

size

public IntPointer size()

returns the array of sizes, or NULL if the matrix is not allocated

size

public int size(int i)

returns the size of i-th matrix dimension (or 0)

dims

public int dims()

returns the matrix dimensionality

nzcount

public long nzcount()

returns the number of non-zero elements (=the number of hash table nodes)

hash

public long hash(int i0)

computes the element hash value (1D case)

hash

public long hash(int i0,
        int i1)

computes the element hash value (2D case)

hash

public long hash(int i0,
        int i1,
        int i2)

computes the element hash value (3D case)

hash

public long hash(IntPointer idx)

computes the element hash value (nD case)

hash

public long hash(IntBuffer idx)

hash

public long hash(int[] idx)

ptr

public BytePointer ptr(int i0,
              boolean createMissing,
              SizeTPointer hashval)

returns pointer to the specified element (1D case)

ptr

public BytePointer ptr(int i0,
              boolean createMissing)

ptr

public BytePointer ptr(int i0,
              int i1,
              boolean createMissing,
              SizeTPointer hashval)

returns pointer to the specified element (2D case)

ptr

public BytePointer ptr(int i0,
              int i1,
              boolean createMissing)

ptr

public BytePointer ptr(int i0,
              int i1,
              int i2,
              boolean createMissing,
              SizeTPointer hashval)

returns pointer to the specified element (3D case)

ptr

public BytePointer ptr(int i0,
              int i1,
              int i2,
              boolean createMissing)

ptr

public BytePointer ptr(IntPointer idx,
              boolean createMissing,
              SizeTPointer hashval)

returns pointer to the specified element (nD case)

ptr

public BytePointer ptr(IntPointer idx,
              boolean createMissing)

ptr

public ByteBuffer ptr(IntBuffer idx,
             boolean createMissing,
             SizeTPointer hashval)

ptr

public ByteBuffer ptr(IntBuffer idx,
             boolean createMissing)

ptr

public byte[] ptr(int[] idx,
         boolean createMissing,
         SizeTPointer hashval)

ptr

public byte[] ptr(int[] idx,
         boolean createMissing)

erase

public void erase(int i0,
         int i1,
         SizeTPointer hashval)

erases the specified element (2D case)

erase

public void erase(int i0,
         int i1)

erase

public void erase(int i0,
         int i1,
         int i2,
         SizeTPointer hashval)

erases the specified element (3D case)

erase

public void erase(int i0,
         int i1,
         int i2)

erase

public void erase(IntPointer idx,
         SizeTPointer hashval)

erases the specified element (nD case)

erase

public void erase(IntPointer idx)

erase

public void erase(IntBuffer idx,
         SizeTPointer hashval)

erase

public void erase(IntBuffer idx)

erase

public void erase(int[] idx,
         SizeTPointer hashval)

erase

public void erase(int[] idx)

begin

public opencv_core.SparseMatIterator begin()

returns the sparse matrix iterator at the matrix beginning

end

public opencv_core.SparseMatIterator end()

returns the sparse matrix iterator at the matrix end

node

public opencv_core.SparseMat.Node node(long nidx)

returns the value stored in the sparse martix node

newNode

public BytePointer newNode(IntPointer idx,
                  long hashval)

newNode

public ByteBuffer newNode(IntBuffer idx,
                 long hashval)

newNode

public byte[] newNode(int[] idx,
             long hashval)

removeNode

public void removeNode(long hidx,
              long nidx,
              long previdx)

resizeHashTab

public void resizeHashTab(long newsize)

flags

public int flags()

flags

public opencv_core.SparseMat flags(int flags)

hdr

public opencv_core.SparseMat.Hdr hdr()

hdr

public opencv_core.SparseMat hdr(opencv_core.SparseMat.Hdr hdr)