jj2000.j2k.roi.encoder
Class RectROIMaskGenerator

java.lang.Object
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  +--jj2000.j2k.roi.encoder.ROIMaskGenerator
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        +--jj2000.j2k.roi.encoder.RectROIMaskGenerator

public class RectROIMaskGenerator

extends ROIMaskGenerator

This class generates the ROI masks when there are only rectangular ROIs in the image. The ROI mask generation can then be simplified by only calculating the boundaries of the ROI mask in the particular subbands

The values are calculated from the scaling factors of the ROIs. The values with which to scale are equal to u-umin where umin is the lowest scaling factor within the block. The umin value is sent to the entropy coder to be used for scaling the distortion values.

To generate and to store the boundaries of the ROIs, the class SubbandRectROIMask is used. There is one tree of SubbandMasks for each component.

See Also:

SubbandRectROIMask, ROIMaskGenerator, ArbROIMaskGenerator

Field Summary

private int[]	lrxs The lower right xs of the ROIs
private int[]	lrys The lower right ys of the ROIs
private int[]	nrROIs Number of ROIs
private SubbandRectROIMask[]	sMasks The tree of subbandmask.
private int[]	ulxs The upper left xs of the ROIs
private int[]	ulys The upper left ys of the ROIs

Fields inherited from class jj2000.j2k.roi.encoder.ROIMaskGenerator

nrc, roiInTile, rois, tileMaskMade

Constructor Summary

RectROIMaskGenerator(ROI[] ROIs, int nrc)
The constructor of the mask generator.

Method Summary

boolean	getROIMask(DataBlkInt db, Subband sb, int magbits, int c) This functions gets a DataBlk the size of the current code-block and fills this block with the ROI mask.
void	makeMask(Subband sb, int magbits, int n) This function generates the ROI mask for the entire tile.
java.lang.String	toString() This function returns the relevant data of the mask generator

Methods inherited from class jj2000.j2k.roi.encoder.ROIMaskGenerator

getROIs, tileChanged

Methods inherited from class java.lang.Object

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

Field Detail

ulxs

private int[] ulxs

The upper left xs of the ROIs

ulys

private int[] ulys

The upper left ys of the ROIs

lrxs

private int[] lrxs

The lower right xs of the ROIs

lrys

private int[] lrys

The lower right ys of the ROIs

nrROIs

private int[] nrROIs

Number of ROIs

sMasks

private SubbandRectROIMask[] sMasks

The tree of subbandmask. One for each component

Constructor Detail

RectROIMaskGenerator

public RectROIMaskGenerator(ROI[] ROIs,
                            int nrc)

The constructor of the mask generator. The constructor is called with the ROI data. This data is stored in arrays that are used to generate the SubbandRectROIMask trees for each component.

Parameters:

ROIs - The ROI info.

nrc - number of components.

Method Detail

getROIMask

public boolean getROIMask(DataBlkInt db,
                          Subband sb,
                          int magbits,
                          int c)

This functions gets a DataBlk the size of the current code-block and fills this block with the ROI mask.

In order to get the mask for a particular Subband, the subband tree is traversed and at each decomposition, the ROI masks are computed. The roi bondaries for each subband are stored in the SubbandRectROIMask tree.

Specified by:

getROIMask in class ROIMaskGenerator

Parameters:

db - The data block that is to be filled with the mask

sb - The root of the subband tree to which db belongs

magbits - The max number of magnitude bits in any code-block

c - The component for which to get the mask

Returns:

Whether or not a mask was needed for this tile

toString

public java.lang.String toString()

This function returns the relevant data of the mask generator

Overrides:

toString in class java.lang.Object

makeMask

public void makeMask(Subband sb,
                     int magbits,
                     int n)

This function generates the ROI mask for the entire tile. The mask is generated for one component. This method is called once for each tile and component.

Specified by:

makeMask in class ROIMaskGenerator

Parameters:

sb - The root of the subband tree used in the decomposition

n - component number

magbits - The max number of magnitude bits in any code-block