jj2000.j2k.image

Class ImgDataJoiner

java.lang.Object

jj2000.j2k.image.ImgDataJoiner

All Implemented Interfaces:

BlkImgDataSrc, ImgData

public class ImgDataJoiner
extends Object
implements BlkImgDataSrc

This class implements the ImgData interface and allows to obtain data from different sources. Here, one source is represented by an ImgData and a component index. The typical use of this class is when the encoder needs different components (Red, Green, Blue, alpha, ...) from different input files (i.e. from different ImgReader objects).

All input ImgData must not be tiled (i.e. must have only 1 tile) and the image origin must be the canvas origin. The different inputs can have different dimensions though (this will lead to different subsampling factors for each component).

The input ImgData and component index list must be defined when constructing this class and can not be modified later.

See Also:

ImgData, ImgReader

Constructor Summary

Constructors

Constructor and Description
ImgDataJoiner(BlkImgDataSrc[] imD, int[] cIdx) Class constructor.

Method Summary

Modifier and Type	Method and Description
DataBlk	getCompData(DataBlk blk, int c) Returns, in the blk argument, a block of image data containing the specifed rectangular area, in the specified component.
int	getCompImgHeight(int n) Returns the height in pixels of the specified component in the overall image.
int	getCompImgWidth(int c) Returns the width in pixels of the specified component in the overall image.
int	getCompSubsX(int c) Returns the component subsampling factor in the horizontal direction, for the specified component.
int	getCompSubsY(int c) Returns the component subsampling factor in the vertical direction, for the specified component.
int	getCompULX(int c) Returns the horizontal coordinate of the upper-left corner of the specified component in the current tile.
int	getCompULY(int c) Returns the vertical coordinate of the upper-left corner of the specified component in the current tile.
int	getFixedPoint(int c) Returns the position of the fixed point in the specified component.
int	getImgHeight() Returns the overall height of the image in pixels.
int	getImgULX() Returns the horizontal coordinate of the image origin, the top-left corner, in the canvas system, on the reference grid.
int	getImgULY() Returns the vertical coordinate of the image origin, the top-left corner, in the canvas system, on the reference grid.
int	getImgWidth() Returns the overall width of the image in pixels.
DataBlk	getInternCompData(DataBlk blk, int c) Returns, in the blk argument, a block of image data containing the specifed rectangular area, in the specified component.
int	getNomRangeBits(int c) Returns the number of bits, referred to as the "range bits", corresponding to the nominal range of the data in the specified component.
int	getNomTileHeight() Returns the nominal tiles height
int	getNomTileWidth() Returns the nominal tiles width
int	getNumComps() Returns the number of components in the image.
int	getNumTiles() Returns the total number of tiles in the image.
Point	getNumTiles(Point co) Returns the number of tiles in the horizontal and vertical directions.
Point	getTile(Point co) Returns the coordinates of the current tile.
int	getTileCompHeight(int t, int c) Returns the height in pixels of the specified tile-component.
int	getTileCompWidth(int t, int c) Returns the width in pixels of the specified tile-component
int	getTileHeight() Returns the overall height of the current tile in pixels.
int	getTileIdx() Returns the index of the current tile, relative to a standard scan-line order.
int	getTilePartULX() Returns the horizontal tile partition offset in the reference grid
int	getTilePartULY() Returns the vertical tile partition offset in the reference grid
int	getTileWidth() Returns the overall width of the current tile in pixels.
void	nextTile() Advances to the next tile, in standard scan-line order (by rows then columns).
void	setTile(int x, int y) Changes the current tile, given the new coordinates.
String	toString() Returns a string of information about the object, more than 1 line long.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

ImgDataJoiner

public ImgDataJoiner(BlkImgDataSrc[] imD,
                     int[] cIdx)

Class constructor. Each input BlkImgDataSrc and its component index must appear in the order wanted for the output components.
Example: Reading R,G,B components from 3 PGM files.
BlkImgDataSrc[] idList =
{
new ImgReaderPGM(new BEBufferedRandomAccessFile("R.pgm", "r")),
new ImgReaderPGM(new BEBufferedRandomAccessFile("G.pgm", "r")),
new ImgReaderPGM(new BEBufferedRandomAccessFile("B.pgm", "r"))
};
int[] compIdx = {0,0,0};
ImgDataJoiner idj = new ImgDataJoiner(idList, compIdx);

Of course, the 2 arrays must have the same length (This length is the number of output components). The image width and height are definded to be the maximum values of all the input ImgData.

Parameters:

imD - The list of input BlkImgDataSrc in an array.

cIdx - The component index associated with each ImgData.

Method Detail

getTileWidth

public int getTileWidth()

Returns the overall width of the current tile in pixels. This is the tile's width without accounting for any component subsampling.

Specified by:

getTileWidth in interface ImgData

Returns:

The total current tile's width in pixels.

getTileHeight

public int getTileHeight()

Returns the overall height of the current tile in pixels. This is the tile's height without accounting for any component subsampling.

Specified by:

getTileHeight in interface ImgData

Returns:

The total current tile's height in pixels.

getNomTileWidth

public int getNomTileWidth()

Returns the nominal tiles width

Specified by:

getNomTileWidth in interface ImgData

getNomTileHeight

public int getNomTileHeight()

Returns the nominal tiles height

Specified by:

getNomTileHeight in interface ImgData

getImgWidth

public int getImgWidth()

Returns the overall width of the image in pixels. This is the image's width without accounting for any component subsampling or tiling.

Specified by:

getImgWidth in interface ImgData

Returns:

The total image's width in pixels.

getImgHeight

public int getImgHeight()

Returns the overall height of the image in pixels. This is the image's height without accounting for any component subsampling or tiling.

Specified by:

getImgHeight in interface ImgData

Returns:

The total image's height in pixels.

getNumComps

public int getNumComps()

Returns the number of components in the image.

Specified by:

getNumComps in interface ImgData

Returns:

The number of components in the image.

getCompSubsX

public int getCompSubsX(int c)

Returns the component subsampling factor in the horizontal direction, for the specified component. This is, approximately, the ratio of dimensions between the reference grid and the component itself, see the 'ImgData' interface desription for details.

Specified by:

getCompSubsX in interface ImgData

Parameters:

c - The index of the component (between 0 and N-1)

Returns:

The horizontal subsampling factor of component 'c'

See Also:

ImgData

getCompSubsY

public int getCompSubsY(int c)

Returns the component subsampling factor in the vertical direction, for the specified component. This is, approximately, the ratio of dimensions between the reference grid and the component itself, see the 'ImgData' interface desription for details.

Specified by:

getCompSubsY in interface ImgData

Parameters:

c - The index of the component (between 0 and N-1)

Returns:

The vertical subsampling factor of component 'c'

See Also:

ImgData

getTileCompWidth

public int getTileCompWidth(int t,
                            int c)

Returns the width in pixels of the specified tile-component

Specified by:

getTileCompWidth in interface ImgData

Parameters:

t - Tile index

c - The index of the component, from 0 to N-1.

Returns:

The width in pixels of component c in tilet.

getTileCompHeight

public int getTileCompHeight(int t,
                             int c)

Returns the height in pixels of the specified tile-component.

Specified by:

getTileCompHeight in interface ImgData

Parameters:

t - The tile index.

c - The index of the component, from 0 to N-1.

Returns:

The height in pixels of component c in the current tile.

getCompImgWidth

public int getCompImgWidth(int c)

Returns the width in pixels of the specified component in the overall image.

Specified by:

getCompImgWidth in interface ImgData

Parameters:

c - The index of the component, from 0 to N-1.

Returns:

The width in pixels of component c in the overall image.

getCompImgHeight

public int getCompImgHeight(int n)

Returns the height in pixels of the specified component in the overall image.

Specified by:

getCompImgHeight in interface ImgData

Parameters:

n - The index of the component, from 0 to N-1.

Returns:

The height in pixels of component n in the overall image.

getNomRangeBits

public int getNomRangeBits(int c)

Returns the number of bits, referred to as the "range bits", corresponding to the nominal range of the data in the specified component. If this number is b then for unsigned data the nominal range is between 0 and 2^b-1, and for signed data it is between -2^(b-1) and 2^(b-1)-1. For floating point data this value is not applicable.

Specified by:

getNomRangeBits in interface ImgData

Parameters:

c - The index of the component.

Returns:

The number of bits corresponding to the nominal range of the data. Fro floating-point data this value is not applicable and the return value is undefined.

getFixedPoint

public int getFixedPoint(int c)

Returns the position of the fixed point in the specified component. This is the position of the least significant integral (i.e. non-fractional) bit, which is equivalent to the number of fractional bits. For instance, for fixed-point values with 2 fractional bits, 2 is returned. For floating-point data this value does not apply and 0 should be returned. Position 0 is the position of the least significant bit in the data.

Specified by:

getFixedPoint in interface BlkImgDataSrc

Parameters:

c - The index of the component.

Returns:

The position of the fixed-point, which is the same as the number of fractional bits. For floating-point data 0 is returned.

getInternCompData

public DataBlk getInternCompData(DataBlk blk,
                                 int c)

Returns, in the blk argument, a block of image data containing the specifed rectangular area, in the specified component. The data is returned, as a reference to the internal data, if any, instead of as a copy, therefore the returned data should not be modified.

The rectangular area to return is specified by the 'ulx', 'uly', 'w' and 'h' members of the 'blk' argument, relative to the current tile. These members are not modified by this method. The 'offset' and 'scanw' of the returned data can be arbitrary. See the 'DataBlk' class.

This method, in general, is more efficient than the 'getCompData()' method since it may not copy the data. However if the array of returned data is to be modified by the caller then the other method is probably preferable.

If the data array in blk is null, then a new one is created if necessary. The implementation of this interface may choose to return the same array or a new one, depending on what is more efficient. Therefore, the data array in blk prior to the method call should not be considered to contain the returned data, a new array may have been created. Instead, get the array from blk after the method has returned.

The returned data may have its 'progressive' attribute set. In this case the returned data is only an approximation of the "final" data.

Specified by:

getInternCompData in interface BlkImgDataSrc

Parameters:

blk - Its coordinates and dimensions specify the area to return, relative to the current tile. Some fields in this object are modified to return the data.

c - The index of the component from which to get the data.

Returns:

The requested DataBlk

See Also:

getCompData(jj2000.j2k.image.DataBlk, int)

getCompData

public DataBlk getCompData(DataBlk blk,
                           int c)

Returns, in the blk argument, a block of image data containing the specifed rectangular area, in the specified component. The data is returned, as a copy of the internal data, therefore the returned data can be modified "in place".

The rectangular area to return is specified by the 'ulx', 'uly', 'w' and 'h' members of the 'blk' argument, relative to the current tile. These members are not modified by this method. The 'offset' of the returned data is 0, and the 'scanw' is the same as the block's width. See the 'DataBlk' class.

This method, in general, is less efficient than the 'getInternCompData()' method since, in general, it copies the data. However if the array of returned data is to be modified by the caller then this method is preferable.

If the data array in 'blk' is 'null', then a new one is created. If the data array is not 'null' then it is reused, and it must be large enough to contain the block's data. Otherwise an 'ArrayStoreException' or an 'IndexOutOfBoundsException' is thrown by the Java system.

The returned data may have its 'progressive' attribute set. In this case the returned data is only an approximation of the "final" data.

Specified by:

getCompData in interface BlkImgDataSrc

Parameters:

blk - Its coordinates and dimensions specify the area to return, relative to the current tile. If it contains a non-null data array, then it must be large enough. If it contains a null data array a new one is created. Some fields in this object are modified to return the data.

c - The index of the component from which to get the data.

Returns:

The requested DataBlk

See Also:

getInternCompData(jj2000.j2k.image.DataBlk, int)

setTile

public void setTile(int x,
                    int y)

Changes the current tile, given the new coordinates. An IllegalArgumentException is thrown if the coordinates do not correspond to a valid tile.

Specified by:

setTile in interface ImgData

Parameters:

x - The horizontal coordinate of the tile.

y - The vertical coordinate of the new tile.

nextTile

public void nextTile()

Advances to the next tile, in standard scan-line order (by rows then columns). A NoNextElementException is thrown if the current tile is the last one (i.e. there is no next tile). This default implementation assumes no tiling, so NoNextElementException() is always thrown.

Specified by:

nextTile in interface ImgData

getTile

public Point getTile(Point co)

Returns the coordinates of the current tile. This default implementation assumes no-tiling, so (0,0) is returned.

Specified by:

getTile in interface ImgData

Parameters:

co - If not null this object is used to return the information. If null a new one is created and returned.

Returns:

The current tile's coordinates.

getTileIdx

public int getTileIdx()

Returns the index of the current tile, relative to a standard scan-line order. This default implementations assumes no tiling, so 0 is always returned.

Specified by:

getTileIdx in interface ImgData

Returns:

The current tile's index (starts at 0).

getCompULX

public int getCompULX(int c)

Returns the horizontal coordinate of the upper-left corner of the specified component in the current tile.

Specified by:

getCompULX in interface ImgData

Parameters:

c - The component index.

getCompULY

public int getCompULY(int c)

Returns the vertical coordinate of the upper-left corner of the specified component in the current tile.

Specified by:

getCompULY in interface ImgData

Parameters:

c - The component index.

getTilePartULX

public int getTilePartULX()

Returns the horizontal tile partition offset in the reference grid

Specified by:

getTilePartULX in interface ImgData

getTilePartULY

public int getTilePartULY()

Returns the vertical tile partition offset in the reference grid

Specified by:

getTilePartULY in interface ImgData

getImgULX

public int getImgULX()

Returns the horizontal coordinate of the image origin, the top-left corner, in the canvas system, on the reference grid.

Specified by:

getImgULX in interface ImgData

Returns:

The horizontal coordinate of the image origin in the canvas system, on the reference grid.

getImgULY

public int getImgULY()

Returns the vertical coordinate of the image origin, the top-left corner, in the canvas system, on the reference grid.

Specified by:

getImgULY in interface ImgData

Returns:

The vertical coordinate of the image origin in the canvas system, on the reference grid.

getNumTiles

public Point getNumTiles(Point co)

Returns the number of tiles in the horizontal and vertical directions. This default implementation assumes no tiling, so (1,1) is always returned.

Specified by:

getNumTiles in interface ImgData

Parameters:

co - If not null this object is used to return the information. If null a new one is created and returned.

Returns:

The number of tiles in the horizontal (Point.x) and vertical (Point.y) directions.

getNumTiles

public int getNumTiles()

Returns the total number of tiles in the image. This default implementation assumes no tiling, so 1 is always returned.

Specified by:

getNumTiles in interface ImgData

Returns:

The total number of tiles in the image.

toString

public String toString()

Returns a string of information about the object, more than 1 line long. The information string includes information from the several input ImgData (their toString() method are called one after the other).

Overrides:

toString in class Object

Returns:

A string of information about the object.