ucar.jpeg.jj2000.j2k.image
Class Tiler

java.lang.Object
  extended by ucar.jpeg.jj2000.j2k.image.ImgDataAdapter
      extended by ucar.jpeg.jj2000.j2k.image.Tiler
All Implemented Interfaces:
BlkImgDataSrc, ImgData

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
 
Fields inherited from class ucar.jpeg.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 c)
          Returns, in the blk argument, a block of image data containing the specifed rectangular area, in 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 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 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.
 Coord getTilingOrigin(Coord co)
          Returns the tiling origin, referred to as '(xt0siz,yt0siz)' in the codestream header (SIZ marker segment).
 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.
 String toString()
          Returns a String object representing Tiler's informations
 
Methods inherited from class ucar.jpeg.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, wait, wait, wait
 
Methods inherited from interface ucar.jpeg.jj2000.j2k.image.ImgData
getCompImgHeight, getCompImgWidth, getCompSubsX, getCompSubsY, getImgHeight, getImgWidth, getNomRangeBits, getNumComps
 

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.

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:
IllegalArgumentException - If src is tiled or "canvased", or if the arguments do not satisfy the specified constraints.
Method Detail

getTileWidth

public final 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
Overrides:
getTileWidth in class ImgDataAdapter
Returns:
The total current tile width in pixels.

getTileHeight

public final int getTileHeight()
Returns the overall height of the current tile in pixels. This is the tile's width without accounting for any component subsampling.

Specified by:
getTileHeight in interface ImgData
Overrides:
getTileHeight in class ImgDataAdapter
Returns:
The total current tile height in pixels.

getTileCompWidth

public final int getTileCompWidth(int t,
                                  int c)
Returns the width in pixels of the specified tile-component.

Specified by:
getTileCompWidth in interface ImgData
Overrides:
getTileCompWidth in class ImgDataAdapter
Parameters:
t - Tile index
c - The index of the component, from 0 to N-1.
Returns:
The width of specified tile-component.

getTileCompHeight

public final int getTileCompHeight(int t,
                                   int c)
Returns the height in pixels of the specified tile-component.

Specified by:
getTileCompHeight in interface ImgData
Overrides:
getTileCompHeight in class ImgDataAdapter
Parameters:
t - The tile index.
c - The index of the component, from 0 to N-1.
Returns:
The height of specified tile-component.

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(ucar.jpeg.jj2000.j2k.image.DataBlk, int)

getCompData

public final 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(ucar.jpeg.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.

Specified by:
setTile in interface ImgData
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).

Specified by:
nextTile in interface ImgData
Overrides:
nextTile in class ImgDataAdapter

getTile

public final Coord getTile(Coord co)
Returns the horizontal and vertical indexes of the current tile.

Specified by:
getTile in interface ImgData
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.

Specified by:
getTileIdx in interface ImgData
Overrides:
getTileIdx in class ImgDataAdapter
Returns:
The current tile's index (starts at 0).

getCompULX

public final 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
Overrides:
getCompULX in class ImgDataAdapter
Parameters:
c - The component index.

getCompULY

public final 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
Overrides:
getCompULY in class ImgDataAdapter
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
Overrides:
getTilePartULX in class ImgDataAdapter

getTilePartULY

public int getTilePartULY()
Returns the vertical tile partition offset in the reference grid

Specified by:
getTilePartULY in interface ImgData
Overrides:
getTilePartULY in class ImgDataAdapter

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.

Specified by:
getImgULX in interface ImgData
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.

Specified by:
getImgULY in interface ImgData
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.

Specified by:
getNumTiles in interface ImgData
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.

Specified by:
getNumTiles in interface ImgData
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.

Specified by:
getNomTileWidth in interface ImgData
Overrides:
getNomTileWidth in class ImgDataAdapter
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.

Specified by:
getNomTileHeight in interface ImgData
Overrides:
getNomTileHeight in class ImgDataAdapter
Returns:
The nominal tile width, in the reference grid.

getTilingOrigin

public final Coord getTilingOrigin(Coord co)
Returns the tiling origin, referred to as '(xt0siz,yt0siz)' in the codestream header (SIZ marker segment).

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 String toString()
Returns a String object representing Tiler's informations

Overrides:
toString in class Object
Returns:
Tiler's infos in a string


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