BitstreamReaderAgent (Bio-Formats API)

java.lang.Object
- jj2000.j2k.codestream.reader.BitstreamReaderAgent

All Implemented Interfaces:

CodedCBlkDataSrcDec, InvWTData, MultiResImgData

Direct Known Subclasses:

FileBitstreamReaderAgent
```
public abstract class BitstreamReaderAgent
extends Object
implements CodedCBlkDataSrcDec
```
This is the generic interface for bit stream reader agents. A bit stream reader agent is an entity that allows reading from a bit stream and requesting compressed code-blocks. It can be a simple file reader, or a network connection, or anything else.
The bit stream reader agent allows to make request for compressed block data in any order. The amount of data returned would normally depend on the data available at the time of the request, be it from a file or from a network connection.
The bit stream reader agent has the notion of a current tile, and coordinates are relative to the current tile, where applicable.
Resolution level 0 is the lowest resolution level, i.e. the LL subband alone.

Field Summary

Fields
Modifier and Type	Field and Description
`protected int`	`anbytes` Actual number of read bytes
`protected float`	`arate` Actual decoding rate in bpp
`protected int`	`ax` The horizontal coordinate of the image origin in the canvas system, on the reference grid.
`protected int`	`ay` The vertical coordinate of the image origin in the canvas system, on the reference grid.
`protected int`	`ctX` The current tile horizontal index
`protected int`	`ctY` The current tile vertical index
`protected int[]`	`culx` The horizontal coordinates of the upper-left corner of the active tile, with respect to the canvas origin, in the component hi-res grid, for each component.
`protected int[]`	`culy` The vertical coordinates of the upper-left corner of the active tile, with respect to the canvas origin, in the component hi-res grid, for each component.
`protected DecoderSpecs`	`decSpec` The decoder specifications
`protected boolean[]`	`derived` Whether or not the components in the current tile uses a derived quantization step size (only relevant in non reversible quantization mode).
`protected int[]`	`gb` Number of guard bits off all component in the current tile.
`protected HeaderDecoder`	`hd` The decoded bit stream header
`protected int`	`imgH` The image width on the hi-res reference grid
`protected int`	`imgW` The image width on the hi-res reference grid
`protected int[]`	`mdl` The maximum number of decompostion levels for each component of the current tile.
`protected int`	`nc` The number of components
`protected int`	`nt` The total number of tiles.
`protected int`	`ntH` The nominal tile height, in the hi-res reference grid
`protected int`	`ntW` The nominal tile width, in the hi-res reference grid
`protected int`	`ntX` The number of tile in the horizontal direction
`protected int`	`ntY` The number of tiles in the vertical direction
`protected 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 hi-res grid, for each component.
`protected 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 hi-res grid, for each component.
`static char`	`OPT_PREFIX` The prefix for bit stream reader options: 'B'
`protected StdDequantizerParams[]`	`params` Dequantization parameters of all subbands and all components in the current tile.
`private static String[][]`	`pinfo` The list of parameters that is accepted by the bit stream readers.
`protected int`	`px` The horizontal coordinate of the tiling origin in the canvas system, on the reference grid.
`protected int`	`py` The vertical coordinate of the tiling origin in the canvas system, on the reference grid.
`protected SubbandSyn[]`	`subbTrees` The subband trees for each component in the current tile.
`protected int`	`targetRes` Image resolution level to generate
`protected int`	`tnbytes` Number of bytes targeted to be read
`protected float`	`trate` Target decoding rate in bpp

Constructor Summary

Constructors
Modifier Constructor and Description

protected BitstreamReaderAgent(HeaderDecoder hd, DecoderSpecs decSpec)
Initializes members of this class.

Constructors
Modifier	Constructor and Description
`protected`	`BitstreamReaderAgent(HeaderDecoder hd, DecoderSpecs decSpec)` Initializes members of this class.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`static BitstreamReaderAgent`	`createInstance(RandomAccessIO in, HeaderDecoder hd, J2KImageReadParamJava j2krparam, DecoderSpecs decSpec, boolean cdstrInfo, HeaderInfo hi)` Creates a bit stream reader of the correct type that works on the provided RandomAccessIO, with the special parameters from the parameter list.
`int`	`getActualNbytes()` Return the actual number of read bytes.
`float`	`getActualRate()` Return the actual decoding rate in bits per pixel.
`int`	`getCbULX()` Returns the vertical code-block partition origin.
`int`	`getCbULY()` Returns the vertical code-block partition origin.
`int`	`getCompImgHeight(int c, int rl)` Returns the height in pixels of the specified component in the overall image, for the given (component) resolution level.
`int`	`getCompImgWidth(int c, int rl)` Returns the width in pixels of the specified component in the overall image, for the given (component) resolution level.
`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`	`getImgHeight(int rl)` Returns the overall height of the image in pixels, for the given resolution level.
`int`	`getImgRes()` Returns the image resolution level to reconstruct from the codestream.
`int`	`getImgULX(int rl)` Returns the horizontal coordinate of the image origin, the top-left corner, in the canvas system, on the reference grid at the specified resolution level.
`int`	`getImgULY(int rl)` Returns the vertical coordinate of the image origin, the top-left corner, in the canvas system, on the reference grid at the specified resolution level.
`int`	`getImgWidth(int rl)` Returns the overall width of the image in pixels, for the given (image) resolution level.
`int`	`getNomTileHeight()` Returns the nominal tile height
`int`	`getNomTileWidth()` Returns the nominal tile 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.
`static String[][]`	`getParameterInfo()` Returns the parameters that are used in this class and implementing classes.
`int`	`getPPX(int t, int c, int rl)` Returns the precinct partition width for the specified tile-component and (tile-component) resolution level.
`int`	`getPPY(int t, int c, int rl)` Returns the precinct partition height for the specified tile-component and (tile-component) resolution level.
`int`	`getResULX(int c, int rl)` Returns the horizontal coordinate of the upper-left corner of the specified resolution in the given component of the current tile.
`int`	`getResULY(int c, int rl)` Returns the vertical coordinate of the upper-left corner of the specified component in the given component of the current tile.
`SubbandSyn`	`getSynSubbandTree(int t, int c)` Returns the subband tree, for the specified tile-component.
`int`	`getTargetNbytes()` Return the target number of read bytes.
`float`	`getTargetRate()` Return the target decoding rate in bits per pixel.
`Point`	`getTile(Point co)` Returns the indexes of the current tile.
`int`	`getTileCompHeight(int t, int c, int rl)` Returns the height in pixels of the specified tile-component for the given (tile-component) resolution level.
`int`	`getTileCompWidth(int t, int c, int rl)` Returns the width in pixels of the specified tile-component for the given (tile-component) resolution level.
`int`	`getTileHeight(int rl)` Returns the overall height of the current tile in pixels, for the given resolution level.
`int`	`getTileIdx()` Returns the index of the current tile, relative to a standard scan-line order.
`int`	`getTilePartULX()` Returns the horizontal offset of tile partition
`int`	`getTilePartULY()` Returns the vertical offset of tile partition
`int`	`getTileWidth(int rl)` Returns the overall width of the current tile in pixels for the given (tile) resolution level.
`protected void`	`initSubbandsFields(int c, SubbandSyn sb)` Initialises subbands fields, such as code-blocks dimension and number of magnitude bits, in the subband tree.
`abstract void`	`nextTile()` Advances to the next tile, in standard scan-line order (by rows then columns).
`abstract void`	`setTile(int x, int y)` Changes the current tile, given the new indexes.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface jj2000.j2k.entropy.decoder.CodedCBlkDataSrcDec
getCodeBlock

- Field Detail
  - decSpec
```
protected DecoderSpecs decSpec
```
    The decoder specifications
  - derived
```
protected boolean[] derived
```
    Whether or not the components in the current tile uses a derived quantization step size (only relevant in non reversible quantization mode). This field is actualized by the setTile method in FileBitstreamReaderAgent.
    
    See Also:
    
    initSubbandsFields(int, jj2000.j2k.wavelet.synthesis.SubbandSyn)
  - gb
```
protected int[] gb
```
    Number of guard bits off all component in the current tile. This field is actualized by the setTile method in FileBitstreamReaderAgent.
    
    See Also:
    
    initSubbandsFields(int, jj2000.j2k.wavelet.synthesis.SubbandSyn)
  - params
```
protected StdDequantizerParams[] params
```
    Dequantization parameters of all subbands and all components in the current tile. The value is actualized by the setTile method in FileBitstreamReaderAgent.
    
    See Also:
    
    initSubbandsFields(int, jj2000.j2k.wavelet.synthesis.SubbandSyn)
  - OPT_PREFIX
```
public static final char OPT_PREFIX
```
    The prefix for bit stream reader options: 'B'
    
    See Also:
    
    Constant Field Values
  - pinfo
```
private static final String[][] pinfo
```
    The list of parameters that is accepted by the bit stream readers. They start with 'B'.
  - mdl
```
protected int[] mdl
```
    The maximum number of decompostion levels for each component of the current tile. It means that component c has mdl[c]+1 resolution levels (indexed from 0 to mdl[c])
  - nc
```
protected final int nc
```
    The number of components
  - targetRes
```
protected int targetRes
```
    Image resolution level to generate
  - subbTrees
```
protected SubbandSyn[] subbTrees
```
    The subband trees for each component in the current tile. Each element in the array is the root element of the subband tree for a component. The number of magnitude bits in each subband (magBits member variable) is not initialized.
  - imgW
```
protected final int imgW
```
    The image width on the hi-res reference grid
  - imgH
```
protected final int imgH
```
    The image width on the hi-res reference grid
  - ax
```
protected final int ax
```
    The horizontal coordinate of the image origin in the canvas system, on the reference grid.
  - ay
```
protected final int ay
```
    The vertical coordinate of the image origin in the canvas system, on the reference grid.
  - px
```
protected final int px
```
    The horizontal coordinate of the tiling origin in the canvas system, on the reference grid.
  - py
```
protected final int py
```
    The vertical coordinate of the tiling origin in the canvas system, on the reference grid.
  - offX
```
protected 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 hi-res grid, for each component.
  - offY
```
protected 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 hi-res grid, for each component.
  - culx
```
protected final int[] culx
```
    The horizontal coordinates of the upper-left corner of the active tile, with respect to the canvas origin, in the component hi-res grid, for each component.
  - culy
```
protected final int[] culy
```
    The vertical coordinates of the upper-left corner of the active tile, with respect to the canvas origin, in the component hi-res grid, for each component.
  - ntW
```
protected final int ntW
```
    The nominal tile width, in the hi-res reference grid
  - ntH
```
protected final int ntH
```
    The nominal tile height, in the hi-res reference grid
  - ntX
```
protected final int ntX
```
    The number of tile in the horizontal direction
  - ntY
```
protected final int ntY
```
    The number of tiles in the vertical direction
  - nt
```
protected final int nt
```
    The total number of tiles.
  - ctX
```
protected int ctX
```
    The current tile horizontal index
  - ctY
```
protected int ctY
```
    The current tile vertical index
  - hd
```
protected final HeaderDecoder hd
```
    The decoded bit stream header
  - tnbytes
```
protected int tnbytes
```
    Number of bytes targeted to be read
  - anbytes
```
protected int anbytes
```
    Actual number of read bytes
  - trate
```
protected float trate
```
    Target decoding rate in bpp
  - arate
```
protected float arate
```
    Actual decoding rate in bpp
- Constructor Detail
  - BitstreamReaderAgent
```
protected BitstreamReaderAgent(HeaderDecoder hd,
                               DecoderSpecs decSpec)
```
    Initializes members of this class. This constructor takes a HeaderDecoder object. This object must be initialized by the constructor of the implementing class from the header of the bit stream.
    
    Parameters:
    
    hd - The decoded header of the bit stream from where to initialize the values.
    
    decSpec - The decoder specifications
- Method Detail
  - getCbULX
```
public final int getCbULX()
```
    Returns the vertical code-block partition origin. Allowable values are 0 and 1, nothing else.
    
    Specified by:
    
    getCbULX in interface InvWTData
  - getCbULY
```
public int getCbULY()
```
    Returns the vertical code-block partition origin. Allowable values are 0 and 1, nothing else.
    
    Specified by:
    
    getCbULY in interface InvWTData
  - getNumComps
```
public final int getNumComps()
```
    Returns the number of components in the image.
    
    Specified by:
    
    getNumComps in interface MultiResImgData
    
    Returns:
    
    The number of components in the image.
  - getCompSubsX
```
public final 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 MultiResImgData
    
    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 MultiResImgData
    
    Parameters:
    
    c - The index of the component (between 0 and C-1)
    
    Returns:
    
    The vertical subsampling factor of component 'c'
    
    See Also:
    
    ImgData
  - getTileWidth
```
public int getTileWidth(int rl)
```
    Returns the overall width of the current tile in pixels for the given (tile) resolution level. This is the tile's width without accounting for any component subsampling.
    Note: Tile resolution level indexes may be different from tile-component resolution index. They are indeed indexed starting from the lowest number of decomposition levels of each component of the tile.
    For an image (1 tile) with 2 components (component 0 having 2 decomposition levels and component 1 having 3 decomposition levels), the first (tile-)component has 3 resolution levels and the second one has 4 resolution levels, whereas the tile has only 3 resolution levels available.
    
    Specified by:
    
    getTileWidth in interface MultiResImgData
    
    Parameters:
    
    rl - The (tile) resolution level.
    
    Returns:
    
    The current tile's width in pixels.
  - getTileHeight
```
public int getTileHeight(int rl)
```
    Returns the overall height of the current tile in pixels, for the given resolution level. This is the tile's height without accounting for any component subsampling.
    Note: Tile resolution level indexes may be different from tile-component resolution index. They are indeed indexed starting from the lowest number of decomposition levels of each component of the tile.
    For an image (1 tile) with 2 components (component 0 having 2 decomposition levels and component 1 having 3 decomposition levels), the first (tile-)component has 3 resolution levels and the second one has 4 resolution levels, whereas the tile has only 3 resolution levels available.
    
    Specified by:
    
    getTileHeight in interface MultiResImgData
    
    Parameters:
    
    rl - The (tile) resolution level.
    
    Returns:
    
    The total current tile's height in pixels.
  - getImgWidth
```
public int getImgWidth(int rl)
```
    Returns the overall width of the image in pixels, for the given (image) resolution level. This is the image's width without accounting for any component subsampling or tiling.
    Note: Image resolution level indexes may differ from tile-component resolution index. They are indeed indexed starting from the lowest number of decomposition levels of each component of each tile.
    Example: For an image (1 tile) with 2 components (component 0 having 2 decomposition levels and component 1 having 3 decomposition levels), the first (tile-) component has 3 resolution levels and the second one has 4 resolution levels, whereas the image has only 3 resolution levels available.
    
    Specified by:
    
    getImgWidth in interface MultiResImgData
    
    Parameters:
    
    rl - The image resolution level.
    
    Returns:
    
    The total image's width in pixels.
  - getImgHeight
```
public int getImgHeight(int rl)
```
    Returns the overall height of the image in pixels, for the given resolution level. This is the image's height without accounting for any component subsampling or tiling.
    Note: Image resolution level indexes may differ from tile-component resolution index. They are indeed indexed starting from the lowest number of decomposition levels of each component of each tile.
    Example: For an image (1 tile) with 2 components (component 0 having 2 decomposition levels and component 1 having 3 decomposition levels), the first (tile-) component has 3 resolution levels and the second one has 4 resolution levels, whereas the image has only 3 resolution levels available.
    
    Specified by:
    
    getImgHeight in interface MultiResImgData
    
    Parameters:
    
    rl - The image resolution level, from 0 to L.
    
    Returns:
    
    The total image's height in pixels.
  - getImgULX
```
public int getImgULX(int rl)
```
    Returns the horizontal coordinate of the image origin, the top-left corner, in the canvas system, on the reference grid at the specified resolution level.
    Note: Image resolution level indexes may differ from tile-component resolution index. They are indeed indexed starting from the lowest number of decomposition levels of each component of each tile.
    Example: For an image (1 tile) with 2 components (component 0 having 2 decomposition levels and component 1 having 3 decomposition levels), the first (tile-) component has 3 resolution levels and the second one has 4 resolution levels, whereas the image has only 3 resolution levels available.
    
    Specified by:
    
    getImgULX in interface MultiResImgData
    
    Parameters:
    
    rl - The resolution level, from 0 to L.
    
    Returns:
    
    The horizontal coordinate of the image origin in the canvas system, on the reference grid.
  - getImgULY
```
public int getImgULY(int rl)
```
    Returns the vertical coordinate of the image origin, the top-left corner, in the canvas system, on the reference grid at the specified resolution level.
    Note: Image resolution level indexes may differ from tile-component resolution index. They are indeed indexed starting from the lowest number of decomposition levels of each component of each tile.
    Example: For an image (1 tile) with 2 components (component 0 having 2 decomposition levels and component 1 having 3 decomposition levels), the first (tile-) component has 3 resolution levels and the second one has 4 resolution levels, whereas the image has only 3 resolution levels available.
    
    Specified by:
    
    getImgULY in interface MultiResImgData
    
    Parameters:
    
    rl - The resolution level, from 0 to L.
    
    Returns:
    
    The vertical coordinate of the image origin in the canvas system, on the reference grid.
  - getTileCompWidth
```
public final int getTileCompWidth(int t,
                                  int c,
                                  int rl)
```
    Returns the width in pixels of the specified tile-component for the given (tile-component) resolution level.
    
    Specified by:
    
    getTileCompWidth in interface MultiResImgData
    
    Parameters:
    
    t - The tile index
    
    c - The index of the component, from 0 to N-1.
    
    rl - The resolution level, from 0 to L.
    
    Returns:
    
    The width in pixels of component c in tile t for resolution level rl.
  - getTileCompHeight
```
public final int getTileCompHeight(int t,
                                   int c,
                                   int rl)
```
    Returns the height in pixels of the specified tile-component for the given (tile-component) resolution level.
    
    Specified by:
    
    getTileCompHeight in interface MultiResImgData
    
    Parameters:
    
    t - The tile index.
    
    c - The index of the component, from 0 to N-1.
    
    rl - The resolution level, from 0 to L.
    
    Returns:
    
    The height in pixels of component c in the current tile.
  - getCompImgWidth
```
public final int getCompImgWidth(int c,
                                 int rl)
```
    Returns the width in pixels of the specified component in the overall image, for the given (component) resolution level.
    Note: Component resolution level indexes may differ from tile-component resolution index. They are indeed indexed starting from the lowest number of decomposition levels of same component of each tile.
    Example: For an image (2 tiles) with 1 component (tile 0 having 2 decomposition levels and tile 1 having 3 decomposition levels), the first tile(-component) has 3 resolution levels and the second one has 4 resolution levels, whereas the component has only 3 resolution levels available.
    
    Specified by:
    
    getCompImgWidth in interface MultiResImgData
    
    Parameters:
    
    c - The index of the component, from 0 to N-1.
    
    rl - The resolution level, from 0 to L.
    
    Returns:
    
    The width in pixels of component c in the overall image.
  - getCompImgHeight
```
public final int getCompImgHeight(int c,
                                  int rl)
```
    Returns the height in pixels of the specified component in the overall image, for the given (component) resolution level.
    Note: Component resolution level indexes may differ from tile-component resolution index. They are indeed indexed starting from the lowest number of decomposition levels of same component of each tile.
    Example: For an image (2 tiles) with 1 component (tile 0 having 2 decomposition levels and tile 1 having 3 decomposition levels), the first tile(-component) has 3 resolution levels and the second one has 4 resolution levels, whereas the component has only 3 resolution levels available.
    
    Specified by:
    
    getCompImgHeight in interface MultiResImgData
    
    Parameters:
    
    c - The index of the component, from 0 to N-1.
    
    rl - The resolution level, from 0 to L.
    
    Returns:
    
    The height in pixels of component c in the overall image.
  - setTile
```
public abstract void setTile(int x,
                             int y)
```
    Changes the current tile, given the new indexes. An IllegalArgumentException is thrown if the indexes do not correspond to a valid tile.
    
    Specified by:
    
    setTile in interface MultiResImgData
    
    Parameters:
    
    x - The horizontal indexes the tile.
    
    y - The vertical indexes of the new tile.
  - nextTile
```
public abstract 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 MultiResImgData
  - getTile
```
public final Point getTile(Point co)
```
    Returns the indexes of the current tile. These are the horizontal and vertical indexes of the current tile.
    
    Specified by:
    
    getTile in interface MultiResImgData
    
    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 indexes (vertical and horizontal 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 MultiResImgData
    
    Returns:
    
    The current tile's index (starts at 0).
  - getResULX
```
public final int getResULX(int c,
                           int rl)
```
    Returns the horizontal coordinate of the upper-left corner of the specified resolution in the given component of the current tile.
    
    Specified by:
    
    getResULX in interface MultiResImgData
    
    Parameters:
    
    c - The component index.
    
    rl - The resolution level index.
  - getResULY
```
public final int getResULY(int c,
                           int rl)
```
    Returns the vertical coordinate of the upper-left corner of the specified component in the given component of the current tile.
    
    Specified by:
    
    getResULY in interface MultiResImgData
    
    Parameters:
    
    c - The component index.
    
    rl - The resolution level index.
  - getNumTiles
```
public final Point getNumTiles(Point co)
```
    Returns the number of tiles in the horizontal and vertical directions.
    
    Specified by:
    
    getNumTiles in interface MultiResImgData
    
    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 final int getNumTiles()
```
    Returns the total number of tiles in the image.
    
    Specified by:
    
    getNumTiles in interface MultiResImgData
    
    Returns:
    
    The total number of tiles in the image.
  - getSynSubbandTree
```
public final SubbandSyn getSynSubbandTree(int t,
                                          int c)
```
    Returns the subband tree, for the specified tile-component. This method returns the root element of the subband tree structure, see Subband and SubbandSyn. The tree comprises all the available resolution levels.
    Note: this method is not able to return subband tree for a tile different than the current one.
    
    The number of magnitude bits ('magBits' member variable) for each subband is not initialized.
    
    Specified by:
    
    getSynSubbandTree in interface InvWTData
    
    Specified by:
    
    getSynSubbandTree in interface MultiResImgData
    
    Parameters:
    
    t - The tile index
    
    c - The index of the component, from 0 to C-1.
    
    Returns:
    
    The root of the tree structure.
  - createInstance
```
public static BitstreamReaderAgent createInstance(RandomAccessIO in,
                                                  HeaderDecoder hd,
                                                  J2KImageReadParamJava j2krparam,
                                                  DecoderSpecs decSpec,
                                                  boolean cdstrInfo,
                                                  HeaderInfo hi)
                                           throws IOException
```
    Creates a bit stream reader of the correct type that works on the provided RandomAccessIO, with the special parameters from the parameter list.
    
    Parameters:
    
    in - The RandomAccessIO source from which to read the bit stream.
    
    hd - Header of the codestream.
    
    j2krparam - The parameters applicable to the bit stream read (other parameters may also be present).
    
    decSpec - The decoder specifications
    
    cdstrInfo - Whether or not to print information found in codestream.
    
    hi - Reference to the HeaderInfo instance.
    
    Throws:
    
    IOException - If an I/O error occurs while reading initial data from the bit stream.
    
    IllegalArgumentException - If an unrecognised bit stream reader option is present.
  - getParameterInfo
```
public static String[][] getParameterInfo()
```
    Returns the parameters that are used in this class and implementing classes. It returns a 2D String array. Each of the 1D arrays is for a different option, and they have 3 elements. The first element is the option name, the second one is the synopsis and the third one is a long description of what the parameter is. The synopsis or description may be 'null', in which case it is assumed that there is no synopsis or description of the option, respectively. Null may be returned if no options are supported.
    
    Returns:
    
    the options name, their synopsis and their explanation, or null if no options are supported.
  - getPPX
```
public final int getPPX(int t,
                        int c,
                        int rl)
```
    Returns the precinct partition width for the specified tile-component and (tile-component) resolution level.
    
    Parameters:
    
    t - the tile index
    
    c - The index of the component (between 0 and N-1)
    
    rl - The resolution level, from 0 to L.
    
    Returns:
    
    the precinct partition width for the specified component, resolution level and tile.
  - getPPY
```
public final int getPPY(int t,
                        int c,
                        int rl)
```
    Returns the precinct partition height for the specified tile-component and (tile-component) resolution level.
    
    Parameters:
    
    t - The tile index
    
    c - The index of the component (between 0 and N-1)
    
    rl - The resolution level, from 0 to L.
    
    Returns:
    
    The precinct partition height in the specified component, for the specified resolution level, for the current tile.
  - initSubbandsFields
```
protected void initSubbandsFields(int c,
                                  SubbandSyn sb)
```
    Initialises subbands fields, such as code-blocks dimension and number of magnitude bits, in the subband tree. The nominal code-block width/height depends on the precincts dimensions if used. The way the number of magnitude bits is computed depends on the quantization type (reversible, derived, expounded).
    
    Parameters:
    
    c - The component index
    
    sb - The subband tree to be initialised.
  - getImgRes
```
public int getImgRes()
```
    Returns the image resolution level to reconstruct from the codestream. This value cannot be computed before every main and tile headers are read.
    
    Returns:
    
    The image resolution level
  - getTargetRate
```
public float getTargetRate()
```
    Return the target decoding rate in bits per pixel.
    
    Returns:
    
    Target decoding rate in bpp.
  - getActualRate
```
public float getActualRate()
```
    Return the actual decoding rate in bits per pixel.
    
    Returns:
    
    Actual decoding rate in bpp.
  - getTargetNbytes
```
public int getTargetNbytes()
```
    Return the target number of read bytes.
    
    Returns:
    
    Target decoding rate in bytes.
  - getActualNbytes
```
public int getActualNbytes()
```
    Return the actual number of read bytes.
    
    Returns:
    
    Actual decoding rate in bytes.
  - getTilePartULX
```
public int getTilePartULX()
```
    Returns the horizontal offset of tile partition
    
    Specified by:
    
    getTilePartULX in interface MultiResImgData
  - getTilePartULY
```
public int getTilePartULY()
```
    Returns the vertical offset of tile partition
    
    Specified by:
    
    getTilePartULY in interface MultiResImgData
  - getNomTileWidth
```
public int getNomTileWidth()
```
    Returns the nominal tile width
    
    Specified by:
    
    getNomTileWidth in interface MultiResImgData
  - getNomTileHeight
```
public int getNomTileHeight()
```
    Returns the nominal tile height
    
    Specified by:
    
    getNomTileHeight in interface MultiResImgData

Class BitstreamReaderAgent

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface jj2000.j2k.entropy.decoder.CodedCBlkDataSrcDec

Field Detail

decSpec

derived

gb

params

OPT_PREFIX

pinfo

mdl

nc

targetRes

subbTrees

imgW

imgH

ax

ay

px

py

offX

offY

culx

culy

ntW

ntH

ntX

ntY

nt

ctX

ctY

hd

tnbytes

anbytes

trate

arate

Constructor Detail

BitstreamReaderAgent

Method Detail

getCbULX

getCbULY

getNumComps

getCompSubsX

getCompSubsY

getTileWidth

getTileHeight

getImgWidth

getImgHeight

getImgULX

getImgULY

getTileCompWidth

getTileCompHeight

getCompImgWidth

getCompImgHeight

setTile

nextTile

getTile

getTileIdx

getResULX

getResULY

getNumTiles

getNumTiles

getSynSubbandTree

createInstance

getParameterInfo

getPPX

getPPY

initSubbandsFields

getImgRes

getTargetRate

getActualRate

getTargetNbytes

getActualNbytes

getTilePartULX

getTilePartULY

getNomTileWidth

getNomTileHeight