jj2000.j2k.roi.encoder

Class RectROIMaskGenerator

java.lang.Object

jj2000.j2k.roi.encoder.ROIMaskGenerator

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

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

nrc, roiInTile, rois, tileMaskMade

Constructor Summary

Constructors

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

Method Summary

Modifier and Type	Method and Description
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.
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

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.

maxShift - The flag indicating use of Maxshift method.

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 String toString()

This function returns the relevant data of the mask generator

Overrides:

toString in class 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