jj2000.j2k.image.ImgDataConverter Maven / Gradle / Ivy
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/*
* $RCSfile: ImgDataConverter.java,v $
* $Revision: 1.1 $
* $Date: 2005/02/11 05:02:13 $
* $State: Exp $
*
* Interface: ImgDataConverter
*
* Description: The abstract class for classes that provide
* Image Data Convertres (int -> float, float->int).
*
*
*
* COPYRIGHT:
*
* This software module was originally developed by Raphaël Grosbois and
* Diego Santa Cruz (Swiss Federal Institute of Technology-EPFL); Joel
* Askelöf (Ericsson Radio Systems AB); and Bertrand Berthelot, David
* Bouchard, Félix Henry, Gerard Mozelle and Patrice Onno (Canon Research
* Centre France S.A) in the course of development of the JPEG2000
* standard as specified by ISO/IEC 15444 (JPEG 2000 Standard). This
* software module is an implementation of a part of the JPEG 2000
* Standard. Swiss Federal Institute of Technology-EPFL, Ericsson Radio
* Systems AB and Canon Research Centre France S.A (collectively JJ2000
* Partners) agree not to assert against ISO/IEC and users of the JPEG
* 2000 Standard (Users) any of their rights under the copyright, not
* including other intellectual property rights, for this software module
* with respect to the usage by ISO/IEC and Users of this software module
* or modifications thereof for use in hardware or software products
* claiming conformance to the JPEG 2000 Standard. Those intending to use
* this software module in hardware or software products are advised that
* their use may infringe existing patents. The original developers of
* this software module, JJ2000 Partners and ISO/IEC assume no liability
* for use of this software module or modifications thereof. No license
* or right to this software module is granted for non JPEG 2000 Standard
* conforming products. JJ2000 Partners have full right to use this
* software module for his/her own purpose, assign or donate this
* software module to any third party and to inhibit third parties from
* using this software module for non JPEG 2000 Standard conforming
* products. This copyright notice must be included in all copies or
* derivative works of this software module.
*
* Copyright (c) 1999/2000 JJ2000 Partners.
* */
package jj2000.j2k.image;
/**
* This class is responsible of all data type conversions. It should be used,
* at encoder side, between Tiler and ForwardWT modules and, at decoder side,
* between InverseWT/CompDemixer and ImgWriter modules. The conversion is
* realized when a block of data is requested: if source and destination data
* type are the same one, it does nothing, else appropriate cast is done. All
* the methods of the 'ImgData' interface are implemented by the
* 'ImgDataAdapter' class that is the superclass of this one, so they don't
* need to be reimplemented by subclasses.
* */
public class ImgDataConverter extends ImgDataAdapter implements BlkImgDataSrc {
/** The block used to request data from the source in the case that a
* conversion seems necessary. It can be either int or float at
* initialization time. It will be checked (and corrected if necessary) by
* the source whenever necessary */
private DataBlk srcBlk = new DataBlkInt();
/** The source of image data */
private BlkImgDataSrc src;
/** The number of fraction bits in the casted ints */
private int fp;
/**
* Constructs a new ImgDataConverter object that operates on the specified
* source of image data.
*
* @param imgSrc The source from where to get the data to be transformed
*
* @param fp The number of fraction bits in the casted ints
*
* @see BlkImgDataSrc
* */
public ImgDataConverter(BlkImgDataSrc imgSrc, int fp) {
super(imgSrc);
src = imgSrc;
this.fp=fp;
}
/**
* Constructs a new ImgDataConverter object that operates on the specified
* source of image data.
*
* @param imgSrc The source from where to get the data to be transformed
*
* @see BlkImgDataSrc
* */
public ImgDataConverter(BlkImgDataSrc imgSrc) {
super(imgSrc);
src = imgSrc;
fp = 0;
}
/**
* 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.
*
* @param c The index of the component.
*
* @return The position of the fixed-point, which is the same as the
* number of fractional bits.
* */
public int getFixedPoint(int c){
return fp;
}
/**
* Returns, in the blk argument, a block of image data containing the
* specifed rectangular area, in the specified component, using the
* 'transfer type' specified in the block given as argument. 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.
*
* @param 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.
*
* @param c The index of the component from which to get the data.
*
* @see #getInternCompData
* */
public DataBlk getCompData(DataBlk blk, int c){
return getData(blk,c,false);
}
/**
* Returns, in the blk argument, a block of image data containing the
* specifed rectangular area, in the specified component, using the
* 'transfer type' defined in the block given as argument. 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.
*
*
If source data and expected data (blk) are using the same type,
* block returned without any modification. If not appropriate cast is
* used.
*
*
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.
*
* @param 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.
*
* @param c The index of the component from which to get the data.
*
* @return The requested DataBlk
*
* @see #getCompData
* */
public final DataBlk getInternCompData(DataBlk blk, int c){
return getData(blk,c,true);
}
/**
* Implements the 'getInternCompData()' and the 'getCompData()'
* methods. The 'intern' flag signals which of the two methods should run
* as.
*
* @param blk The data block to get.
*
* @param c The index of the component from which to get the data.
*
* @param intern If true behave as 'getInternCompData(). Otherwise behave
* as 'getCompData()'
*
* @return The requested data block
*
* @see #getInternCompData
*
* @see #getCompData
* */
private DataBlk getData(DataBlk blk, int c, boolean intern) {
DataBlk reqBlk; // Reference to block used in request to source
// Keep request data type
int otype = blk.getDataType();
if (otype == srcBlk.getDataType()) {
// Probably requested type is same as source type
reqBlk = blk;
}
else {
// Probably requested type is not the same as source type
reqBlk = srcBlk;
// We need to copy requested coordinates and size
reqBlk.ulx = blk.ulx;
reqBlk.uly = blk.uly;
reqBlk.w = blk.w;
reqBlk.h = blk.h;
}
// Get source data block
if (intern) {
// We can use the intern variant
srcBlk = src.getInternCompData(reqBlk,c);
}
else {
// Do not use the intern variant. Note that this is not optimal
// since if we are going to convert below then we could have used
// the intern variant. But there is currently no way to know if we
// will need to do conversion or not before getting the data.
srcBlk = src.getCompData(reqBlk,c);
}
// Check if casting is needed
if(srcBlk.getDataType()==otype){
return srcBlk;
}
int i;
int k,kSrc,kmin;
float mult;
int w=srcBlk.w;
int h=srcBlk.h;
switch(otype){
case DataBlk.TYPE_FLOAT: // Cast INT -> FLOAT
float farr[];
int srcIArr[];
// Get data array from resulting blk
farr = (float[]) blk.getData();
if (farr == null || farr.length < w*h) {
farr = new float[w*h];
blk.setData(farr);
}
blk.scanw = srcBlk.w;
blk.offset = 0;
blk.progressive = srcBlk.progressive;
srcIArr=(int[]) srcBlk.getData();
// Cast data from source to blk
fp=src.getFixedPoint(c);
if(fp!=0){
mult=1.0f/(1<=0; i--) {
for (kmin = k-w; k>kmin; k--, kSrc--) {
farr[k]=((srcIArr[kSrc]*mult));
}
// Jump to geggining of next line in source
kSrc -= srcBlk.scanw - w;
}
}
else{
for (i=h-1, k=w*h-1, kSrc =
srcBlk.offset+(h-1)*srcBlk.scanw+w-1; i>=0; i--) {
for (kmin = k-w; k>kmin; k--, kSrc--) {
farr[k]=((float)(srcIArr[kSrc]));
}
// Jump to geggining of next line in source
kSrc -= srcBlk.scanw - w;
}
}
break; // End of cast INT-> FLOAT
case DataBlk.TYPE_INT: // cast FLOAT -> INT
int iarr[];
float srcFArr[];
// Get data array from resulting blk
iarr = (int[]) blk.getData();
if (iarr == null || iarr.length < w*h) {
iarr = new int[w*h];
blk.setData(iarr);
}
blk.scanw = srcBlk.w;
blk.offset = 0;
blk.progressive = srcBlk.progressive;
srcFArr=(float[]) srcBlk.getData();
// Cast data from source to blk
if(fp!=0){
mult=(float)(1<=0; i--) {
for (kmin = k-w; k>kmin; k--, kSrc--) {
if (srcFArr[kSrc] > 0.0f) {
iarr[k] = (int) (srcFArr[kSrc]*mult+0.5f);
}
else {
iarr[k] = (int) (srcFArr[kSrc]*mult-0.5f);
}
}
// Jump to geggining of next line in source
kSrc -= srcBlk.scanw - w;
}
}
else{
for (i=h-1, k=w*h-1, kSrc =
srcBlk.offset+(h-1)*srcBlk.scanw+w-1; i>=0; i--) {
for (kmin = k-w; k>kmin; k--, kSrc--) {
if (srcFArr[kSrc] > 0.0f) {
iarr[k] = (int) (srcFArr[kSrc]+0.5f);
}
else {
iarr[k] = (int) (srcFArr[kSrc]-0.5f);
}
}
// Jump to geggining of next line in source
kSrc -= srcBlk.scanw - w;
}
}
break; // End cast FLOAT -> INT
default:
throw
new IllegalArgumentException("Only integer and float data "+
"are "+
"supported by JJ2000");
}
return blk;
}
}