ImageMatcher< Tag, Allocator > Struct Template Reference

The ImageMatcher structure provides fast algorithm of searching of similar images. More...

#include <SimdImageMatcher.hpp>

Data Structures
struct	Hash
	The Hash structure is used for fast image matching. More...
struct	Result
	The Result structure is a result of matching current image and images added before to ImageMatcher. More...

Public Types
enum	HashType {   Hash16x16 ,   Hash32x32 ,   Hash64x64 }
typedef Simd::View< Allocator >	View
typedef std::shared_ptr< Hash >	HashPtr
typedef std::vector< Result >	Results

Public Member Functions
bool	Empty () const
size_t	Size () const
bool	Init (double threshold=0.05, HashType type=Hash16x16, size_t number=0, bool normalized=false)
HashPtr	Create (const View &view, const Tag &tag)
bool	Find (const HashPtr &hash, Results &results)
void	Add (const HashPtr &hash)
void	Skip (const Hash *hash)

Detailed Description

template<class Tag, template< class > class Allocator>
struct Simd::ImageMatcher< Tag, Allocator >

The ImageMatcher structure provides fast algorithm of searching of similar images.

Using example (the filter removes duplicates from the list):

#include "Simd/SimdImageMatcher.hpp"

typedef Simd::ImageMatcher<size_t, Simd::Allocator> ImageMatcher;
typedef std::shared_ptr<View> ViewPtr;
typedef std::vector<ViewPtr> ViewPtrs;

void FilterDuplicates(const ViewPtrs & src, double threshold, ViewPtrs & dst)
{
    ImageMatcher matcher;
    matcher.Init(threshold, ImageMatcher::Hash16x16, src.size());
    for (size_t i = 0; i < src.size(); ++i)
    {
        ImageMatcher::HashPtr hash = matcher.Create(*src[i], i);
        ImageMatcher::Results results;
        if (!matcher.Find(hash, results))
        {
            matcher.Add(hash);
            dst.push_back(src[i]);
        }
    }
}

Member Typedef Documentation

View

typedef Simd::View<Allocator> View

An image type definition.

HashPtr

typedef std::shared_ptr<Hash> HashPtr

A shared pointer to Hash structure.

Results

typedef std::vector<Result> Results

A vector with results.

Member Enumeration Documentation

HashType

enum HashType

Describes size of reduced image used in image Hash.

Enumerator
Hash16x16	16x16 reduced image size.
Hash32x32	32x32 reduced image size.
Hash64x64	32x32 reduced image size.

Member Function Documentation

Empty()

bool Empty

(

)

const

Signalizes true if ImageMatcher is initialized.

Returns

true if ImageMatcher is initialized.

Size()

size_t Size

(

)

const

Gets total number of images added to ImageMatcher.

Returns

total number of images added to ImageMatcher.

Init()

bool Init	(	double	threshold = 0.05,
		HashType	type = Hash16x16,
		size_t	number = 0,
		bool	normalized = false
	)

Initializes ImageMatcher for search.

Parameters

[in]	threshold	- a maximal mean squared difference for similar images. By default it is equal to 0.05.
[in]	type	- a type of Hash used for matching. By default it is equal to ImageMatcher::Hash16x16.
[in]	number	- an estimated total number of images used for matching. By default it is equal to 0.
[in]	normalized	- a flag signalized that images have normalized histogram. By default it is false.

Returns

the result of the operation.

Create()

HashPtr Create	(	const View &	view,
		const Tag &	tag
	)

Creates hash for given image.

Parameters

[in]	view	- an input image.
[in]	tag	- a tag of arbitrary type.

Returns

the smart pointer to Hash for image matching.

Find()

bool Find	(	const HashPtr &	hash,
		Results &	results
	)

Finds all similar images earlier added to ImageMatcher for given image.

Parameters

[in]	hash	- a smart pointer to hash of the image.
[out]	results	- a list of found similar images.

Returns

true if similar images were found.

Add()

void Add

(

const HashPtr &

hash

)

Adds given image to ImageMatcher.

Parameters

[in]

hash

- a smart pointer to hash of the image.

Skip()

void Skip

(

const Hash *

hash

)

Skips searching of the image in ImageMatcher.

Parameters

[in]

hash

- a pointer to hash of the image.