Package jj2000.j2k.entropy.encoder

Class EBCOTRateAllocator

java.lang.Object

jj2000.j2k.image.ImgDataAdapter

jj2000.j2k.entropy.encoder.PostCompRateAllocator

jj2000.j2k.entropy.encoder.EBCOTRateAllocator

All Implemented Interfaces:

ImgData

public class EBCOTRateAllocator
extends PostCompRateAllocator

This implements the EBCOT post compression rate allocation algorithm. This algorithm finds the most suitable truncation points for the set of code-blocks, for each layer target bitrate. It works by first collecting the rate distortion info from all code-blocks, in all tiles and all components, and then running the rate-allocation on the whole image at once, for each layer.

This implementation also provides some timing features. They can be enabled by setting the 'DO_TIMING' constant of this class to true and recompiling. The timing uses the 'System.currentTimeMillis()' Java API call, which returns wall clock time, not the actual CPU time used. The timing results will be printed on the message output. Since the times reported are wall clock times and not CPU usage times they can not be added to find the total used time (i.e. some time might be counted in several places). When timing is disabled ('DO_TIMING' is false) there is no penalty if the compiler performs some basic optimizations. Even if not the penalty should be negligeable.

See Also:

PostCompRateAllocator, CodedCBlkDataSrcEnc, CodestreamWriter

Field Summary

Fields inherited from class jj2000.j2k.entropy.encoder.PostCompRateAllocator

numLayers, OPT_PREFIX, src, wp

Fields inherited from class jj2000.j2k.image.ImgDataAdapter

imgdatasrc, tIdx

Constructor Summary

Constructors

Constructor	Description
EBCOTRateAllocator(CodedCBlkDataSrcEnc src, LayersInfo lyrs, CodestreamWriter writer, J2KImageWriteParamJava wp)	Initializes the EBCOT rate allocator of entropy coded data.

Method Summary

Modifier and Type	Method	Description
void	finalize()	Prints the timing information, if collected, and calls 'finalize' on the super class.
void	initialize()	Initializes the layers array.
void	runAndWrite()	Runs the rate allocation algorithm and writes the data to the bit stream writer object provided to the constructor.
void	writeCompPosResLy(int t, int rs, int re, int cs, int ce, int[][] lys, int lye)	Write a piece of bit stream according to the COMP_POS_RES_LY_PROG progression mode and between given bounds
void	writeLyResCompPos(int t, int rs, int re, int cs, int ce, int[][] lys, int lye)	Write a piece of bit stream according to the LY_RES_COMP_POS_PROG progression mode and between given bounds
void	writePosCompResLy(int t, int rs, int re, int cs, int ce, int[][] lys, int lye)	Write a piece of bit stream according to the COMP_POS_RES_LY_PROG progression mode and between given bounds
void	writeResLyCompPos(int t, int rs, int re, int cs, int ce, int[][] lys, int lye)	Write a piece of bit stream according to the RES_LY_COMP_POS_PROG progression mode and between given bounds
void	writeResPosCompLy(int t, int rs, int re, int cs, int ce, int[][] lys, int lye)	Write a piece of bit stream according to the RES_POS_COMP_LY_PROG progression mode and between given bounds

Methods inherited from class jj2000.j2k.entropy.encoder.PostCompRateAllocator

createInstance, getNumLayers, getParameterInfo, setHeaderEncoder

Methods inherited from class jj2000.j2k.image.ImgDataAdapter

getCompImgHeight, getCompImgWidth, getCompSubsX, getCompSubsY, getCompULX, getCompULY, getImgHeight, getImgULX, getImgULY, getImgWidth, getNomRangeBits, getNomTileHeight, getNomTileWidth, getNumComps, getNumTiles, getNumTiles, getTile, getTileCompHeight, getTileCompWidth, getTileHeight, getTileIdx, getTilePartULX, getTilePartULY, getTileWidth, nextTile, setTile

Methods inherited from class java.lang.Object

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

Constructor Detail

EBCOTRateAllocator

public EBCOTRateAllocator(CodedCBlkDataSrcEnc src,
                          LayersInfo lyrs,
                          CodestreamWriter writer,
                          J2KImageWriteParamJava wp)

Initializes the EBCOT rate allocator of entropy coded data. The layout of layers, and their bitrate constraints, is specified by the 'lyrs' parameter.

Parameters:

src - The source of entropy coded data.

lyrs - The layers layout specification.

writer - The bit stream writer.

See Also:

ProgressionType

Method Detail

finalize

public void finalize()
              throws Throwable

Prints the timing information, if collected, and calls 'finalize' on the super class.

Overrides:

finalize in class Object

Throws:

Throwable

runAndWrite

public void runAndWrite()
                 throws IOException

Runs the rate allocation algorithm and writes the data to the bit stream writer object provided to the constructor.

Specified by:

runAndWrite in class PostCompRateAllocator

Throws:

IOException

See Also:

PostCompRateAllocator.initialize()

initialize

public void initialize()
                throws IOException

Initializes the layers array. This must be called after the main header has been entirely written or simulated, so as to take its overhead into account. This method will get all the code-blocks and then initialize the target bitrates for each layer, according to the specifications.

Specified by:

initialize in class PostCompRateAllocator

Throws:

IOException

See Also:

PostCompRateAllocator.runAndWrite()

writeResLyCompPos

public void writeResLyCompPos(int t,
                              int rs,
                              int re,
                              int cs,
                              int ce,
                              int[][] lys,
                              int lye)
                       throws IOException

Write a piece of bit stream according to the RES_LY_COMP_POS_PROG progression mode and between given bounds

Parameters:

t - Tile index.

rs - First resolution level index.

re - Last resolution level index.

cs - First component index.

ce - Last component index.

lys - First layer index for each component and resolution.

lye - Index of the last layer.

Throws:

IOException

writeLyResCompPos

public void writeLyResCompPos(int t,
                              int rs,
                              int re,
                              int cs,
                              int ce,
                              int[][] lys,
                              int lye)
                       throws IOException

Write a piece of bit stream according to the LY_RES_COMP_POS_PROG progression mode and between given bounds

Parameters:

t - Tile index.

rs - First resolution level index.

re - Last resolution level index.

cs - First component index.

ce - Last component index.

lys - First layer index for each component and resolution.

lye - Index of the last layer.

Throws:

IOException

writePosCompResLy

public void writePosCompResLy(int t,
                              int rs,
                              int re,
                              int cs,
                              int ce,
                              int[][] lys,
                              int lye)
                       throws IOException

Write a piece of bit stream according to the COMP_POS_RES_LY_PROG progression mode and between given bounds

Parameters:

t - Tile index.

rs - First resolution level index.

re - Last resolution level index.

cs - First component index.

ce - Last component index.

lys - First layer index for each component and resolution.

lye - Index of the last layer.

Throws:

IOException

writeCompPosResLy

public void writeCompPosResLy(int t,
                              int rs,
                              int re,
                              int cs,
                              int ce,
                              int[][] lys,
                              int lye)
                       throws IOException

Write a piece of bit stream according to the COMP_POS_RES_LY_PROG progression mode and between given bounds

Parameters:

t - Tile index.

rs - First resolution level index.

re - Last resolution level index.

cs - First component index.

ce - Last component index.

lys - First layer index for each component and resolution.

lye - Index of the last layer.

Throws:

IOException

writeResPosCompLy

public void writeResPosCompLy(int t,
                              int rs,
                              int re,
                              int cs,
                              int ce,
                              int[][] lys,
                              int lye)
                       throws IOException

Write a piece of bit stream according to the RES_POS_COMP_LY_PROG progression mode and between given bounds

Parameters:

t - Tile index.

rs - First resolution level index.

re - Last resolution level index.

cs - First component index.

ce - Last component index.

lys - First layer index for each component and resolution.

lye - Last layer index.

Throws:

IOException