org.openimaj.feature.local.list

Class MemoryLocalFeatureList<T extends LocalFeature<?,?>>

java.lang.Object

java.util.AbstractCollection<E>

java.util.AbstractList<E>

java.util.ArrayList<T>

org.openimaj.feature.local.list.MemoryLocalFeatureList<T>

Type Parameters:

T - the type of local feature

All Implemented Interfaces:

Serializable, Cloneable, Iterable<T>, Collection<T>, List<T>, RandomAccess, LocalFeatureList<T>, Writeable, WriteableASCII, WriteableBinary, RandomisableList<T>

public class MemoryLocalFeatureList<T extends LocalFeature<?,?>>
extends ArrayList<T>
implements LocalFeatureList<T>

An in-memory list of local features.

Author:

Jonathon Hare (jsh2@ecs.soton.ac.uk)

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected int	cached_veclen

Fields inherited from class java.util.AbstractList

modCount

Fields inherited from interface org.openimaj.feature.local.list.LocalFeatureList

BINARY_HEADER

Constructor Summary

Constructors

Constructor and Description
MemoryLocalFeatureList() Construct an empty feature list
MemoryLocalFeatureList(Collection<? extends T> c) Construct a local feature list from the given collection of local features.
MemoryLocalFeatureList(int veclen) Construct an empty list with the given feature-vector length.
MemoryLocalFeatureList(int veclen, int initialCapacity) Construct an empty list with the given feature-vector length and pre-allocate the underlying array with space for initialCapacity local features.

Method Summary

Methods

Modifier and Type	Method and Description
String	asciiHeader() Header for ascii output.
<Q> Q[]	asDataArray(Q[] a) Get the feature-vector data of the list as a two-dimensional array of data.
byte[]	binaryHeader() Header for binary output.
MemoryLocalFeatureList<T>	filter(LocationFilter locationFilter) Create a new list by applying a LocationFilter to all the elements of this list.
MemoryLocalFeatureList<T>	randomSubList(int nelem) Extract a sublist made up of nelem elements from the this list.
static <T extends LocalFeature<?,?>> MemoryLocalFeatureList<T>	read(BufferedInputStream stream, Class<T> clz) Create a MemoryLocalFeatureList by reading all the local features from the specified stream.
static <T extends LocalFeature<?,?>> MemoryLocalFeatureList<T>	read(File keypointFile, Class<T> clz) Create a MemoryLocalFeatureList by reading all the local features from the specified file.
static <T extends LocalFeature<?,?>> MemoryLocalFeatureList<T>	read(InputStream stream, Class<T> clz) Create a MemoryLocalFeatureList by reading all the local features from the specified stream.
static <T extends LocalFeature<?,?>> MemoryLocalFeatureList<T>	readNoHeader(DataInput in, Class<T> clz) Create a MemoryLocalFeatureList by reading all the local features from the specified DataInput.
void	resetVecLength() Reset the internal feature vector length to the length of the first feature.
MemoryLocalFeatureList<T>	subList(int fromIndex, int toIndex)
int	vecLength() Get the length of the feature-vectors of each local feature if they are constant.
void	writeASCII(PrintWriter out) Write the content of this as ascii to out.
void	writeBinary(DataOutput out) Write the content of this as binary to out.

Methods inherited from class java.util.ArrayList

add, add, addAll, addAll, clear, clone, contains, ensureCapacity, get, indexOf, isEmpty, iterator, lastIndexOf, listIterator, listIterator, remove, remove, removeAll, removeRange, retainAll, set, size, toArray, toArray, trimToSize

Methods inherited from class java.util.AbstractList

equals, hashCode

Methods inherited from class java.util.AbstractCollection

containsAll, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.List

add, add, addAll, addAll, clear, contains, containsAll, equals, get, hashCode, indexOf, isEmpty, iterator, lastIndexOf, listIterator, listIterator, remove, remove, removeAll, retainAll, set, size, toArray, toArray

Field Detail

cached_veclen

protected int cached_veclen

Constructor Detail

MemoryLocalFeatureList

public MemoryLocalFeatureList()

Construct an empty feature list

MemoryLocalFeatureList

public MemoryLocalFeatureList(int veclen)

Construct an empty list with the given feature-vector length.

Parameters:

veclen - the expected length of the feature vectors of each local feature.

MemoryLocalFeatureList

public MemoryLocalFeatureList(Collection<? extends T> c)

Construct a local feature list from the given collection of local features.

Parameters:

c - Collection of local feature to add to the list instance.

MemoryLocalFeatureList

public MemoryLocalFeatureList(int veclen,
                      int initialCapacity)

Construct an empty list with the given feature-vector length and pre-allocate the underlying array with space for initialCapacity local features. The list will automatically grow once initialCapacity is reached.

Parameters:

veclen - the expected length of the feature vectors of each local feature.

initialCapacity - the initial capacity of the list.

Method Detail

read

public static <T extends LocalFeature<?,?>> MemoryLocalFeatureList<T> read(File keypointFile,
                                                           Class<T> clz)
                                                                throws IOException

Create a MemoryLocalFeatureList by reading all the local features from the specified file.

Type Parameters:

T - the type of local feature

Parameters:

keypointFile - the file from which to read the features

clz - the class of local feature

Returns:

a new MemoryLocalFeatureList populated with features from the file

Throws:

IOException - if an error occurs reading the file

read

public static <T extends LocalFeature<?,?>> MemoryLocalFeatureList<T> read(InputStream stream,
                                                           Class<T> clz)
                                                                throws IOException

Create a MemoryLocalFeatureList by reading all the local features from the specified stream.

Type Parameters:

T - the type of local feature

Parameters:

stream - the input stream from which to read the features

clz - the class of local feature

Returns:

a new MemoryLocalFeatureList populated with features from the file

Throws:

IOException - if an error occurs reading the file

read

public static <T extends LocalFeature<?,?>> MemoryLocalFeatureList<T> read(BufferedInputStream stream,
                                                           Class<T> clz)
                                                                throws IOException

Create a MemoryLocalFeatureList by reading all the local features from the specified stream.

Type Parameters:

T - the type of local feature

Parameters:

stream - the input stream from which to read the features

clz - the class of local feature

Returns:

a new MemoryLocalFeatureList populated with features from the file

Throws:

IOException - if an error occurs reading the file

readNoHeader

public static <T extends LocalFeature<?,?>> MemoryLocalFeatureList<T> readNoHeader(DataInput in,
                                                                   Class<T> clz)
                                                                        throws IOException

Create a MemoryLocalFeatureList by reading all the local features from the specified DataInput. Reading of the header is skipped, and it is assumed that the data is in binary format.

Type Parameters:

T - the type of local feature

Parameters:

in - the data input from which to read the features

clz - the class of local feature

Returns:

a new MemoryLocalFeatureList populated with features from the file

Throws:

IOException - if an error occurs reading the file

asDataArray

public <Q> Q[] asDataArray(Q[] a)

Description copied from interface: LocalFeatureList

Get the feature-vector data of the list as a two-dimensional array of data. The number of rows will equal the number of features in the list, and the type must be compatible with the data type of the features themselves.

Specified by:

asDataArray in interface LocalFeatureList<T extends LocalFeature<?,?>>

Type Parameters:

Q - the data type

Parameters:

a - the array to fill

Returns:

the array, filled with the feature-vector data.

randomSubList

public MemoryLocalFeatureList<T> randomSubList(int nelem)

Description copied from interface: RandomisableList

Extract a sublist made up of nelem elements from the this list.

Specified by:

randomSubList in interface RandomisableList<T extends LocalFeature<?,?>>

Parameters:

nelem - number of elements to extract

Returns:

another randomisable list

writeBinary

public void writeBinary(DataOutput out)
                 throws IOException

Description copied from interface: WriteableBinary

Write the content of this as binary to out.

Specified by:

writeBinary in interface WriteableBinary

Parameters:

out - sink to write to

Throws:

IOException - an error writing to out

writeASCII

public void writeASCII(PrintWriter out)
                throws IOException

Description copied from interface: WriteableASCII

Write the content of this as ascii to out.

Specified by:

writeASCII in interface WriteableASCII

Parameters:

out - sink to write to

Throws:

IOException - an error writing to out

binaryHeader

public byte[] binaryHeader()

Description copied from interface: WriteableBinary

Header for binary output. Will be automatically written by IOUtils when using writeBinary().

Specified by:

binaryHeader in interface WriteableBinary

Returns:

header

asciiHeader

public String asciiHeader()

Description copied from interface: WriteableASCII

Header for ascii output. Will be automatically written by IOUtils when using writeASCII().

Specified by:

asciiHeader in interface WriteableASCII

Returns:

header

vecLength

public int vecLength()

Description copied from interface: LocalFeatureList

Get the length of the feature-vectors of each local feature if they are constant. This value is used as instantiate new local features in the case that the local feature has a constructor that takes a single integer.

Specified by:

vecLength in interface LocalFeatureList<T extends LocalFeature<?,?>>

Returns:

the feature-vector length

resetVecLength

public void resetVecLength()

Reset the internal feature vector length to the length of the first feature. You must call this if you change the length of the features within the list.

filter

public MemoryLocalFeatureList<T> filter(LocationFilter locationFilter)

Create a new list by applying a LocationFilter to all the elements of this list. Only items which are accepted by the filter will be added to the new list.

Parameters:

locationFilter - the location filter

Returns:

a filtered list

subList

public MemoryLocalFeatureList<T> subList(int fromIndex,
                                int toIndex)

Specified by:

subList in interface List<T extends LocalFeature<?,?>>

Specified by:

subList in interface LocalFeatureList<T extends LocalFeature<?,?>>

Overrides:

subList in class ArrayList<T extends LocalFeature<?,?>>