jj2000.j2k.image
Class Tiler

java.lang.Object
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  +--jj2000.j2k.image.ImgDataAdapter
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        +--jj2000.j2k.image.Tiler

public class Tiler
extends ImgDataAdapter
implements BlkImgDataSrc

This class places an image in the canvas coordinate system, tiles it, if so specified, and performs the coordinate conversions transparently. The source must be a 'BlkImgDataSrc' which is not tiled and has a the image origin at the canvas origin (i.e. it is not "canvased"), or an exception is thrown by the constructor. A tiled and "canvased" output is given through the 'BlkImgDataSrc' interface. See the 'ImgData' interface for a description of the canvas and tiling.

All tiles produced are rectangular, non-overlapping and their union covers all the image. However, the tiling may not be uniform, depending on the nominal tile size, tiling origin, component subsampling and other factors. Therefore it might not be assumed that all tiles are of the same width and height.

The nominal dimension of the tiles is the maximal one, in the reference grid. All the components of the image have the same number of tiles.

See Also:
ImgData, BlkImgDataSrc

Field Summary
private  int ax
          The horizontal coordinate of the image origin in the canvas system, on the reference grid.
private  int ay
          The vertical coordinate of the image origin in the canvas system, on the reference grid.
private  int[] bh
          The component height in the current active tile, for each component
private  int[] bw
          The component width in the current active tile, for each component
private  int ch
          The height of the current tile, on the reference grid.
private  int cw
          The width of the current tile, on the reference grid.
private  int[] iulx
          The horizontal coordinates of the upper-left corner of the active tile, with respect to the image origin, in the component grid, for each component.
private  int[] iuly
          The vertical coordinates of the upper-left corner of the active tile, with respect to the image origin, in the component grid, for each component.
private  int nh
          The nominal height of the tiles, on the reference grid.
private  int nht
          The number of tiles in the horizontal direction.
private  int nvt
          The number of tiles in the vertical direction.
private  int nw
          The nominal width of the tiles, on the reference grid.
private  int[] offX
          The horizontal offsets of the upper-left corner of the current tile (not active tile) with respect to the canvas origin, in the component grid, for each component.
private  int[] offY
          The vertical offsets of the upper-left corner of the current tile (not active tile) with respect to the canvas origin, in the component grid, for each component.
private  int px
          The horizontal coordinate of the tiling origin in the canvas system, on the reference grid.
private  int py
          The vertical coordinate of the tiling origin in the canvas system, on the reference grid.
private  BlkImgDataSrc src
          The source of image data
private  int tx
          The horizontal index of the current tile
private  int ty
          The vertical index of the current tile
 
Fields inherited from class jj2000.j2k.image.ImgDataAdapter
imgdatasrc, tIdx
 
Constructor Summary
Tiler(BlkImgDataSrc src, int ax, int ay, int px, int py, int nw, int nh)
          Constructs a new tiler with the specified 'BlkImgDataSrc' source, image origin, tiling origin and nominal tile size.
 
Method Summary
 DataBlk getCompData(DataBlk blk, int n)
          Returns, in the blk argument, a block of image data containing the specifed rectangular area, in the specified component.
 int getCompHeight(int c)
          Returns the height in pixels of the specified component in the current tile.
 int getCompWidth(int c)
          Returns the width in pixels of the specified component in the current tile.
 int getFixedPoint(int c)
          Returns the position of the fixed point in the specified component.
 int getHeight()
          Returns the overall height of the current tile 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.
 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 getNomTileHeight()
          Returns the nominal width of the tiles in the reference grid.
 int getNomTileWidth()
          Returns the nominal width of the tiles in the reference grid.
 int getNumTiles()
          Returns the total number of tiles in the image.
 Coord getNumTiles(Coord co)
          Returns the number of tiles in the horizontal and vertical directions.
 Coord getTile(Coord co)
          Returns the horizontal and vertical indexes of the current tile.
 int getTileIdx()
          Returns the index of the current tile, relative to a standard scan-line order.
 Coord getTileOff(Coord co, int c)
          Returns the horizontal and vertical offset of the upper-left corner of the current tile, in the specified component, relative to the canvas origin, in the component coordinates (not in the reference grid coordinates).
 Coord getTilingOrigin(Coord co)
          Returns the tiling origin, refferred to as '(Px,Py)' in the 'ImgData' interface.
 int getULX(int c)
          Returns the horizontal coordinate of the upper-left corner of the active tile, with respect to the canvas origin, in the component coordinates, for the specified component.
 int getULY(int c)
          Returns the vertical coordinate of the upper-left corner of the active tile, with respect to the canvas origin, in the component coordinates, for the specified component.
 int getWidth()
          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 tile indexes.
 java.lang.String toString()
          Returns a String object representing Tiler's informations
 
Methods inherited from class jj2000.j2k.image.ImgDataAdapter
getCompImgHeight, getCompImgWidth, getCompSubsX, getCompSubsY, getImgHeight, getImgWidth, getNomRangeBits, getNumComps
 
Methods inherited from class java.lang.Object
, clone, equals, finalize, getClass, hashCode, notify, notifyAll, registerNatives, wait, wait, wait
 

Field Detail

src

private final BlkImgDataSrc src
The source of image data

ax

private final int ax
The horizontal coordinate of the image origin in the canvas system, on the reference grid.

ay

private final int ay
The vertical coordinate of the image origin in the canvas system, on the reference grid.

px

private final int px
The horizontal coordinate of the tiling origin in the canvas system, on the reference grid.

py

private final int py
The vertical coordinate of the tiling origin in the canvas system, on the reference grid.

nw

private final int nw
The nominal width of the tiles, on the reference grid. If 0 then there is no tiling in that direction.

nh

private final int nh
The nominal height of the tiles, on the reference grid. If 0 then there is no tiling in that direction.

nht

private final int nht
The number of tiles in the horizontal direction.

nvt

private final int nvt
The number of tiles in the vertical direction.

bw

private final int[] bw
The component width in the current active tile, for each component

bh

private final int[] bh
The component height in the current active tile, for each component

offX

private final int[] offX
The horizontal offsets of the upper-left corner of the current tile (not active tile) with respect to the canvas origin, in the component grid, for each component.

offY

private final int[] offY
The vertical offsets of the upper-left corner of the current tile (not active tile) with respect to the canvas origin, in the component grid, for each component.

iulx

private final int[] iulx
The horizontal coordinates of the upper-left corner of the active tile, with respect to the image origin, in the component grid, for each component.

iuly

private final int[] iuly
The vertical coordinates of the upper-left corner of the active tile, with respect to the image origin, in the component grid, for each component.

tx

private int tx
The horizontal index of the current tile

ty

private int ty
The vertical index of the current tile

cw

private int cw
The width of the current tile, on the reference grid.

ch

private int ch
The height of the current tile, on the reference grid.
Constructor Detail

Tiler

public Tiler(BlkImgDataSrc src,
             int ax,
             int ay,
             int px,
             int py,
             int nw,
             int nh)
Constructs a new tiler with the specified 'BlkImgDataSrc' source, image origin, tiling origin and nominal tile size.

It must be noted that 'ax' and 'bx' can not be chosen arbitrarily for multi component images with different component subsampling. This is because not all '(ax,bx)' yield the correct component dimensions (i.e. the component dimensions derived from '(ax,bx)' and the subsampling factors might not be the same as the true component dimensions). See the 'ImgData' interface for component width calculation from '(ax,bx)' and subsampling factors. This is checked by the constructor and an 'IllegalArgumentException' is thrown if an inconsistency occurs.

Parameters:
src - The 'BlkImgDataSrc' source from where to get the image data. It must not be tiled and the image origin must be at '(0,0)' on its canvas.
ax - The horizontal coordinate of the image origin in the canvas system, on the reference grid (i.e. the image's top-left corner in the reference grid).
ay - The vertical coordinate of the image origin in the canvas system, on the reference grid (i.e. the image's top-left corner in the reference grid).
px - The horizontal tiling origin, in the canvas system, on the reference grid. It must satisfy 'px<=ax'.
py - The vertical tiling origin, in the canvas system, on the reference grid. It must satisfy 'py<=ay'.
nw - The nominal tile width, on the reference grid. If 0 then there is no tiling in that direction.
nh - The nominal tile height, on the reference grid. If 0 then there is no tiling in that direction.
Throws:
java.lang.IllegalArgumentException - If src is tiled or "canvased", or if the arguments do not satisfy the specified constraints.
Method Detail

getWidth

public final int getWidth()
Returns the overall width of the current tile in pixels. This is the tile's width without accounting for any component subsampling.
Overrides:
getWidth in class ImgDataAdapter
Returns:
The total current tile width in pixels.

getHeight

public final int getHeight()
Returns the overall height of the current tile in pixels. This is the tile's width without accounting for any component subsampling.
Overrides:
getHeight in class ImgDataAdapter
Returns:
The total current tile height in pixels.

getCompWidth

public final int getCompWidth(int c)
Returns the width in pixels of the specified component in the current tile.
Overrides:
getCompWidth in class ImgDataAdapter
Parameters:
c - The index of the component, from 0 to N-1.
Returns:
The width in pixels of component c in the current tile.

getCompHeight

public final int getCompHeight(int c)
Returns the height in pixels of the specified component in the current tile.
Overrides:
getCompHeight in class ImgDataAdapter
Parameters:
c - The index of the component, from 0 to N-1.
Returns:
The height in pixels of component c in the current tile.

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 final 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 final DataBlk getCompData(DataBlk blk,
                                 int n)
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.
n - 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 final void setTile(int x,
                          int y)
Changes the current tile, given the new tile indexes. An IllegalArgumentException is thrown if the coordinates do not correspond to a valid tile.
Overrides:
setTile in class ImgDataAdapter
Parameters:
x - The horizontal index of the tile.
y - The vertical index of the new tile.

nextTile

public final void nextTile()
Advances to the next tile, in standard scan-line order (by rows then columns). An NoNextElementException is thrown if the current tile is the last one (i.e. there is no next tile).
Overrides:
nextTile in class ImgDataAdapter

getTile

public final Coord getTile(Coord co)
Returns the horizontal and vertical indexes of the current tile.
Overrides:
getTile in class ImgDataAdapter
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 horizontal and vertical indexes..

getTileIdx

public final int getTileIdx()
Returns the index of the current tile, relative to a standard scan-line order.
Overrides:
getTileIdx in class ImgDataAdapter
Returns:
The current tile's index (starts at 0).

getTileOff

public final Coord getTileOff(Coord co,
                              int c)
Returns the horizontal and vertical offset of the upper-left corner of the current tile, in the specified component, relative to the canvas origin, in the component coordinates (not in the reference grid coordinates). These are the coordinates of the current tile's (not active tile) upper-left corner relative to the canvas.
Overrides:
getTileOff in class ImgDataAdapter
Parameters:
co - If not null the object is used to return the values, if null a new one is created and returned.
c - The index of the component (between 0 and N-1).
Returns:
The horizontal and vertical offsets of the upper-left corner of the current tile, for the specified component, relative to the canvas origin, in the component coordinates.

getULX

public final int getULX(int c)
Returns the horizontal coordinate of the upper-left corner of the active tile, with respect to the canvas origin, in the component coordinates, for the specified component.
Overrides:
getULX in class ImgDataAdapter
Parameters:
c - The index of the component (between 0 and N-1)
Returns:
The horizontal coordinate of the upper-left corner of the active tile, with respect to the canvas origin, for component 'c', in the component coordinates.

getULY

public final int getULY(int c)
Returns the vertical coordinate of the upper-left corner of the active tile, with respect to the canvas origin, in the component coordinates, for the specified component.
Overrides:
getULY in class ImgDataAdapter
Parameters:
c - The index of the component (between 0 and N-1)
Returns:
The vertical coordinate of the upper-left corner of the active tile, with respect to the canvas origin, for component 'c', in the component coordinates.

getImgULX

public final int getImgULX()
Returns the horizontal coordinate of the image origin, the top-left corner, in the canvas system, on the reference grid.
Overrides:
getImgULX in class ImgDataAdapter
Returns:
The horizontal coordinate of the image origin in the canvas system, on the reference grid.

getImgULY

public final int getImgULY()
Returns the vertical coordinate of the image origin, the top-left corner, in the canvas system, on the reference grid.
Overrides:
getImgULY in class ImgDataAdapter
Returns:
The vertical coordinate of the image origin in the canvas system, on the reference grid.

getNumTiles

public final Coord getNumTiles(Coord co)
Returns the number of tiles in the horizontal and vertical directions.
Overrides:
getNumTiles in class ImgDataAdapter
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 (Coord.x) and vertical (Coord.y) directions.

getNumTiles

public final int getNumTiles()
Returns the total number of tiles in the image.
Overrides:
getNumTiles in class ImgDataAdapter
Returns:
The total number of tiles in the image.

getNomTileWidth

public final int getNomTileWidth()
Returns the nominal width of the tiles in the reference grid.
Returns:
The nominal tile width, in the reference grid.

getNomTileHeight

public final int getNomTileHeight()
Returns the nominal width of the tiles in the reference grid.
Returns:
The nominal tile width, in the reference grid.

getTilingOrigin

public final Coord getTilingOrigin(Coord co)
Returns the tiling origin, refferred to as '(Px,Py)' in the 'ImgData' interface.
Parameters:
co - If not null this object is used to return the information. If null a new one is created and returned.
Returns:
The coordinate of the tiling origin, in the canvas system, on the reference grid.
See Also:
ImgData

toString

public java.lang.String toString()
Returns a String object representing Tiler's informations
Overrides:
toString in class java.lang.Object
Returns:
Tiler's infos in a string