jj2000.j2k.codestream.reader
Class HeaderDecoder

java.lang.Object
  |
  +--jj2000.j2k.codestream.reader.HeaderDecoder

All Implemented Interfaces:

Markers, ProgressionType, StdEntropyCoderOptions

public class HeaderDecoder

extends java.lang.Object

implements ProgressionType, Markers, StdEntropyCoderOptions

This class reads main and tile-part headers from the codestream given a RandomAccessIO instance located at the beginning of the codestream (i.e just before the SOC marker) or at the beginning of a tile-part (i.e. just before a SOT marker segment) respectively.

A marker segment includes a marker and eventually marker segment parameters. It is designed by the three letters code of the marker associated with the marker segment. JPEG 2000 part 1 defines 6 types of markers segments:

• Delimiting : SOC, SOT, SOD, EOC
• Fixed information: SIZ.
• Functional: COD, COC, RGN, QCD, QCC,POC.
• In bit-stream: SOP, EPH.
• Pointer: TLM, PLM, PLT, PPM, PPT.
• Informational: CRG, COM.

The main header is read when the constructor is called whereas tile-part headers are read when the FileBitstreamReaderAgent instance is created. The reading is done in 2 passes:

1. All marker segments are buffered and their corresponding flag is activated (extractMainMarkSeg and extractTilePartMarkSeg methods).
2. Buffered marker segment are analyzed in a logical way and specifications are stored in appropriate member of DecoderSpecs instance (readFoundMainMarkSeg and readFoundTilePartMarkSeg methods).

Whenever a marker segment is not recognized a warning message is displayed and its length parameter is used to skip it.

The information found in this header is stored in HeaderInfo and DecoderSpecs instances.

See Also:

DecoderSpecs, HeaderInfo, Decoder, FileBitstreamReaderAgent

Field Summary

private int	cb0x The horizontal code-block partition origin
private int	cb0y The vertical code-block partition origin
private static int	COC_FOUND Flag bit for COC marker segment found
private static int	COD_FOUND Flag bit for COD marker segment found
private static int	COM_FOUND Flag bit for COM marker segment found
static int	CRG_FOUND Flag bit for CRG marker segment found
private DecoderSpecs	decSpec The decoder specifications
private java.lang.String	hdStr Current header information in a string
private HeaderInfo	hi The reference to the HeaderInfo instance holding the information found in headers
private java.util.Hashtable	ht HashTable used to store temporary marker segment byte buffers
int	mainHeadOff The offset of the main header in the input stream
private int	nCOCMarkSeg Counts number of COC markers found in the header
private int	nCOMMarkSeg Counts number of COM markers found in the header
private int	nComp The number of components in the image
private int	nfMarkSeg Used to store which markers have been already read, by using flag bits.
private int	nPPMMarkSeg Counts number of PPM markers found in the header
private int[][]	nPPTMarkSeg Counts number of PPT markers found in the header
private int	nQCCMarkSeg Counts number of QCC markers found in the header
private int	nRGNMarkSeg Counts number of RGN markers found in the header
int[]	nTileParts The number of tile parts in each tile
private int	nTiles The number of tiles within the image
static char	OPT_PREFIX The prefix for header decoder options: 'H'
private static java.lang.String[][]	pinfo The list of parameters that is accepted for quantization.
private java.io.ByteArrayOutputStream[]	pkdPktHeaders The packed packet headers if the PPM or PPT markers are used
private static int	PLM_FOUND Flag bit for PLM marker segment found
private static int	PLT_FOUND Flag bit for PLT marker segment found
private static int	POC_FOUND Flag bit for POC marker segment found
static int	PPM_FOUND Flag bit for SOD marker segment found
private byte[][]	pPMMarkerData Array containing the Nppm and Ippm fields of the PPM marker segments
static int	PPT_FOUND Flag bit for SOD marker segment found
(package private) boolean	precinctPartitionIsUsed Is the precinct partition used
private static int	QCC_FOUND Flag bit for QCC marker segment found
private static int	QCD_FOUND Flag bit for QCD marker segment found
private static int	RGN_FOUND Flag bit for RGN marker segment found
private static int	SIZ_FOUND Flag bit for SIZ marker segment found
static int	SOD_FOUND Flag bit for SOD marker segment found
private static int	SOT_FOUND Flag bit for SOT marker segment found
private static int	TILE_RESET The reset mask for new tiles
java.util.Vector	tileOfTileParts Vector containing info as to which tile each tilepart belong
private byte[][][][]	tilePartPkdPktHeaders Array containing the Ippm fields of the PPT marker segments
private static int	TLM_FOUND Flag bit for TLM marker segment found
private boolean	verbose Whether or not to display general information

Fields inherited from interface jj2000.j2k.codestream.ProgressionType

COMP_POS_RES_LY_PROG, LY_RES_COMP_POS_PROG, POS_COMP_RES_LY_PROG, RES_LY_COMP_POS_PROG, RES_POS_COMP_LY_PROG

Fields inherited from interface jj2000.j2k.codestream.Markers

COC, COD, COM, CRG, EOC, EPH, EPH_LENGTH, ERS_SEG_SYMBOLS, ERS_SOP, MAX_COMP_BITDEPTH, MAX_LPPM, MAX_LPPT, PLM, PLT, POC, PPM, PPT, PRECINCT_PARTITION_DEF_SIZE, QCC, QCD, RCOM_GEN_USE, RGN, RSIZ_BASELINE, RSIZ_ER_FLAG, RSIZ_ROI, SCOX_HOR_CB_PART, SCOX_PRECINCT_PARTITION, SCOX_USE_EPH, SCOX_USE_SOP, SCOX_VER_CB_PART, SIZ, SOC, SOD, SOP, SOP_LENGTH, SOT, SQCX_EXP_MASK, SQCX_EXP_SHIFT, SQCX_GB_MSK, SQCX_GB_SHIFT, SQCX_NO_QUANTIZATION, SQCX_SCALAR_DERIVED, SQCX_SCALAR_EXPOUNDED, SRGN_IMPLICIT, SSIZ_DEPTH_BITS, TLM

Fields inherited from interface jj2000.j2k.entropy.StdEntropyCoderOptions

FIRST_BYPASS_PASS_IDX, MAX_CB_AREA, MAX_CB_DIM, MIN_CB_DIM, NUM_EMPTY_PASSES_IN_MS_BP, NUM_NON_BYPASS_MS_BP, NUM_PASSES, OPT_BYPASS, OPT_PRED_TERM, OPT_RESET_MQ, OPT_SEG_SYMBOLS, OPT_TERM_PASS, OPT_VERT_STR_CAUSAL, STRIPE_HEIGHT

Constructor Summary

HeaderDecoder(RandomAccessIO ehs, ParameterList pl, HeaderInfo hi)
Creates a HeaderDecoder instance and read in two passes the main header of the codestream.

Method Summary

void	checkMarkerLength(java.io.DataInputStream ehs, java.lang.String str) Checks that the marker segment length is correct.
BlkImgDataSrc	createChannelDefinitionMapper(BlkImgDataSrc src, ColorSpace csMap) Creates and returns the ChannelDefinitonMapper which maps the input channels to the channel definition for the appropriate colorspace.
BlkImgDataSrc	createColorSpaceMapper(BlkImgDataSrc src, ColorSpace csMap) Creates and returns the EnumeratedColorSpaceMapper corresponding to the information read from the JP2 image file via the ColorSpace parameter.
Dequantizer	createDequantizer(CBlkQuantDataSrcDec src, int[] rb, DecoderSpecs decSpec2) Returns the dequantizer parameters.
EntropyDecoder	createEntropyDecoder(CodedCBlkDataSrcDec src, ParameterList pl) Creates and returns the entropy decoder corresponding to the information read from the codestream header and with the special additional parameters from the parameter list.
BlkImgDataSrc	createPalettizedColorSpaceMapper(BlkImgDataSrc src, ColorSpace csMap) Creates and returns the PalettizedColorSpaceMapper which uses the input samples as indicies into a sample palette to construct the output.
BlkImgDataSrc	createResampler(BlkImgDataSrc src, ColorSpace csMap) Creates and returns the Resampler which converts the input source to one in which all channels have the same number of samples.
ROIDeScaler	createROIDeScaler(CBlkQuantDataSrcDec src, ParameterList pl, DecoderSpecs decSpec2) Creates and returns the ROIDeScaler corresponding to the information read from the codestream header and with the special additional parameters from the parameter list.
private void	extractMainMarkSeg(short marker, RandomAccessIO ehs) This method extract a marker segment from the main header and stores it into a byte buffer for the second pass.
void	extractTilePartMarkSeg(short marker, RandomAccessIO ehs, int tileIdx, int tilePartIdx) This method extracts a marker segment in a tile-part header and stores it into a byte buffer for the second pass.
int	getCbULX() Returns the horizontal code-block partition origin.Allowable values are 0 and 1, nothing else.
int	getCbULY() Returns the vertical code-block partition origin.
int	getCompSubsX(int c) Returns the component sub-sampling factor, with respect to the reference grid, along the horizontal direction for the specified component.
int	getCompSubsY(int c) Returns the component sub-sampling factor, with respect to the reference grid, along the vertical direction for the specified component.
DecoderSpecs	getDecoderSpecs() Return the DecoderSpecs instance filled when reading the headers
int	getImgHeight() Returns the image height in the reference grid.
int	getImgULX() Return the horizontal upper-left coordinate of the image in the reference grid.
int	getImgULY() Return the vertical upper-left coordinate of the image in the reference grid.
int	getImgWidth() Returns the image width in the reference grid.
int	getMaxCompImgHeight() Return the maximum height among all components
int	getMaxCompImgWidth() Return the maximum width among all components
int	getNomTileHeight() Returns the nominal width of the tiles in the reference grid.
int	getNomTileWidth() Returns the nominal width of the tiles in the reference grid.
int	getNumComps() Returns the number of components in the image.
int	getNumFoundMarkSeg() Returns the number of found marker segments in the current header.
int	getNumTiles() Return the number of tiles in the image
int	getOriginalBitDepth(int c) Returns the original bitdepth of the specified component.
java.io.ByteArrayInputStream	getPackedPktHead(int tile) Return the packed packet headers for a given tile.
static java.lang.String[][]	getParameterInfo() Returns the parameters that are used in this class.
int	getPPX(int t, int c, int rl) Returns the precinct partition width for the specified tile-component and resolution level.
int	getPPY(int t, int c, int rl) Returns the precinct partition height for the specified tile-component and resolution level.
Coord	getTilingOrigin(Coord co) Returns the tiling origin, referred to as '(Px,Py)' in the 'ImgData' interface.
boolean	isOriginalSigned(int c) Returns true if the original data of the specified component was signed.
boolean	precinctPartitionUsed() Returns the boolean used to know if the precinct partition is used
private void	readCOC(java.io.DataInputStream ehs, boolean mainh, int tileIdx, int tpIdx) Reads the COC marker segment and realigns the codestream where the next marker should be found.
private void	readCOD(java.io.DataInputStream ehs, boolean mainh, int tileIdx, int tpIdx) Reads a COD marker segment and realigns the codestream where the next marker should be found.
private void	readCOM(java.io.DataInputStream ehs, boolean mainh, int tileIdx, int comIdx) Reads a COM marker segments and realigns the bit stream at the point where the next marker segment should be found.
private void	readCRG(java.io.DataInputStream ehs) Reads a CRG marker segment and checks its length.
private SynWTFilter	readFilter(java.io.DataInputStream ehs, int[] filtIdx) Reads a wavelet filter from the codestream and returns the filter object that implements it.
private void	readFoundMainMarkSeg() Retrieves and reads all marker segments found in the main header during the first pass.
void	readFoundTilePartMarkSeg(int tileIdx, int tpIdx) Retrieves and reads all marker segments previously found in the tile-part header.
private void	readPLM(java.io.DataInputStream ehs) Reads PLM marker segment and realigns the codestream where the next marker should be found.
private void	readPLTFields(java.io.DataInputStream ehs) Reads the PLT fields and realigns the codestream where the next marker should be found.
private void	readPOC(java.io.DataInputStream ehs, boolean mainh, int t, int tpIdx) Reads the POC marker segment and realigns the codestream where the next marker should be found.
private void	readPPM(java.io.DataInputStream ehs) Reads the PPM marker segment of the main header.
private void	readPPT(java.io.DataInputStream ehs, int tile, int tpIdx) Reads the PPT marker segment of the main header.
private void	readQCC(java.io.DataInputStream ehs, boolean mainh, int tileIdx, int tpIdx) Reads a QCC marker segment and realigns the codestream at the point where the next marker should be found.
private void	readQCD(java.io.DataInputStream ehs, boolean mainh, int tileIdx, int tpIdx) Reads a QCD marker segment and realigns the codestream at the point where the next marker should be found.
private void	readRGN(java.io.DataInputStream ehs, boolean mainh, int tileIdx, int tpIdx) Reads the RGN marker segment of the codestream header.
private void	readSIZ(java.io.DataInputStream ehs) Reads the SIZ marker segment and realigns the codestream at the point where the next marker segment should be found.
private void	readTLM(java.io.DataInputStream ehs) Reads TLM marker segment and realigns the codestream where the next marker should be found.
void	resetHeaderMarkers() Method that resets members indicating which markers have already been found
void	setTileOfTileParts(int tile) Sets the tile of each tile part in order.
java.lang.String	toString() Print information about the current header.

Methods inherited from class java.lang.Object

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

Field Detail

OPT_PREFIX

public static final char OPT_PREFIX

The prefix for header decoder options: 'H'

See Also:

Constant Field Values

pinfo

private static final java.lang.String[][] pinfo

The list of parameters that is accepted for quantization. Options for quantization start with 'Q'.

hi

private HeaderInfo hi

The reference to the HeaderInfo instance holding the information found in headers

verbose

private boolean verbose

Whether or not to display general information

hdStr

private java.lang.String hdStr

Current header information in a string

nTiles

private int nTiles

The number of tiles within the image

nTileParts

public int[] nTileParts

The number of tile parts in each tile

nfMarkSeg

private int nfMarkSeg

Used to store which markers have been already read, by using flag bits. The different markers are marked with XXX_FOUND flags, such as SIZ_FOUND

nCOCMarkSeg

private int nCOCMarkSeg

Counts number of COC markers found in the header

nQCCMarkSeg

private int nQCCMarkSeg

Counts number of QCC markers found in the header

nCOMMarkSeg

private int nCOMMarkSeg

Counts number of COM markers found in the header

nRGNMarkSeg

private int nRGNMarkSeg

Counts number of RGN markers found in the header

nPPMMarkSeg

private int nPPMMarkSeg

Counts number of PPM markers found in the header

nPPTMarkSeg

private int[][] nPPTMarkSeg

Counts number of PPT markers found in the header

SIZ_FOUND

private static final int SIZ_FOUND

Flag bit for SIZ marker segment found

See Also:

Constant Field Values

COD_FOUND

private static final int COD_FOUND

Flag bit for COD marker segment found

See Also:

Constant Field Values

COC_FOUND

private static final int COC_FOUND

Flag bit for COC marker segment found

See Also:

Constant Field Values

QCD_FOUND

private static final int QCD_FOUND

Flag bit for QCD marker segment found

See Also:

Constant Field Values

TLM_FOUND

private static final int TLM_FOUND

Flag bit for TLM marker segment found

See Also:

Constant Field Values

PLM_FOUND

private static final int PLM_FOUND

Flag bit for PLM marker segment found

See Also:

Constant Field Values

SOT_FOUND

private static final int SOT_FOUND

Flag bit for SOT marker segment found

See Also:

Constant Field Values

PLT_FOUND

private static final int PLT_FOUND

Flag bit for PLT marker segment found

See Also:

Constant Field Values

QCC_FOUND

private static final int QCC_FOUND

Flag bit for QCC marker segment found

See Also:

Constant Field Values

RGN_FOUND

private static final int RGN_FOUND

Flag bit for RGN marker segment found

See Also:

Constant Field Values

POC_FOUND

private static final int POC_FOUND

Flag bit for POC marker segment found

See Also:

Constant Field Values

COM_FOUND

private static final int COM_FOUND

Flag bit for COM marker segment found

See Also:

Constant Field Values

SOD_FOUND

public static final int SOD_FOUND

Flag bit for SOD marker segment found

See Also:

Constant Field Values

PPM_FOUND

public static final int PPM_FOUND

Flag bit for SOD marker segment found

See Also:

Constant Field Values

PPT_FOUND

public static final int PPT_FOUND

Flag bit for SOD marker segment found

See Also:

Constant Field Values

CRG_FOUND

public static final int CRG_FOUND

Flag bit for CRG marker segment found

See Also:

Constant Field Values

TILE_RESET

private static final int TILE_RESET

The reset mask for new tiles

See Also:

Constant Field Values

ht

private java.util.Hashtable ht

HashTable used to store temporary marker segment byte buffers

nComp

private int nComp

The number of components in the image

cb0x

private int cb0x

The horizontal code-block partition origin

cb0y

private int cb0y

The vertical code-block partition origin

decSpec

private DecoderSpecs decSpec

The decoder specifications

precinctPartitionIsUsed

boolean precinctPartitionIsUsed

Is the precinct partition used

mainHeadOff

public int mainHeadOff

The offset of the main header in the input stream

tileOfTileParts

public java.util.Vector tileOfTileParts

Vector containing info as to which tile each tilepart belong

pPMMarkerData

private byte[][] pPMMarkerData

Array containing the Nppm and Ippm fields of the PPM marker segments

tilePartPkdPktHeaders

private byte[][][][] tilePartPkdPktHeaders

Array containing the Ippm fields of the PPT marker segments

pkdPktHeaders

private java.io.ByteArrayOutputStream[] pkdPktHeaders

The packed packet headers if the PPM or PPT markers are used

Constructor Detail

HeaderDecoder

public HeaderDecoder(RandomAccessIO ehs,
                     ParameterList pl,
                     HeaderInfo hi)
              throws java.io.IOException

Creates a HeaderDecoder instance and read in two passes the main header of the codestream. The first and last marker segments shall be respectively SOC and SOT.

Parameters:

ehs - The encoded header stream where marker segments are extracted.

pl - The ParameterList object of the decoder

hi - The HeaderInfo holding information found in marker segments

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoded header stream.

java.io.EOFException - If the end of the encoded header stream is reached before getting all the data.

CorruptedCodestreamException - If invalid data is found in the codestream main header.

Method Detail

getMaxCompImgHeight

public int getMaxCompImgHeight()

Return the maximum height among all components

Returns:

Maximum component height

getMaxCompImgWidth

public int getMaxCompImgWidth()

Return the maximum width among all components

Returns:

Maximum component width

getImgWidth

public final int getImgWidth()

Returns the image width in the reference grid.

Returns:

The image width in the reference grid

getImgHeight

public final int getImgHeight()

Returns the image height in the reference grid.

Returns:

The image height in the reference grid

getImgULX

public final int getImgULX()

Return the horizontal upper-left coordinate of the image in the reference grid.

Returns:

The horizontal coordinate of the image origin.

getImgULY

public final int getImgULY()

Return the vertical upper-left coordinate of the image in the reference grid.

Returns:

The vertical coordinate of the image origin.

getNomTileWidth

public final int getNomTileWidth()

Returns the nominal width of the tiles in the reference grid.

Returns:

The nominal tile width, in the reference grid.

getNomTileHeight

public final int getNomTileHeight()

Returns the nominal width of the tiles in the reference grid.

Returns:

The nominal tile width, in the reference grid.

getTilingOrigin

public final Coord getTilingOrigin(Coord co)

Returns the tiling origin, referred to as '(Px,Py)' in the 'ImgData' interface.

Parameters:

co - If not null this object is used to return the information. If null a new one is created and returned.

Returns:

The coordinate of the tiling origin, in the canvas system, on the reference grid.

See Also:

ImgData

isOriginalSigned

public final boolean isOriginalSigned(int c)

Returns true if the original data of the specified component was signed. If the data was not signed a level shift has to be applied at the end of the decompression chain.

Parameters:

c - The index of the component

Returns:

True if the original image component was signed.

getOriginalBitDepth

public final int getOriginalBitDepth(int c)

Returns the original bitdepth of the specified component.

Parameters:

c - The index of the component

Returns:

The bitdepth of the component

getNumComps

public final int getNumComps()

Returns the number of components in the image.

Returns:

The number of components in the image.

getCompSubsX

public final int getCompSubsX(int c)

Returns the component sub-sampling factor, with respect to the reference grid, along the horizontal direction for the specified component.

Parameters:

c - The index of the component

Returns:

The component sub-sampling factor X-wise.

getCompSubsY

public final int getCompSubsY(int c)

Returns the component sub-sampling factor, with respect to the reference grid, along the vertical direction for the specified component.

Parameters:

c - The index of the component

Returns:

The component sub-sampling factor Y-wise.

createDequantizer

public final Dequantizer createDequantizer(CBlkQuantDataSrcDec src,
                                           int[] rb,
                                           DecoderSpecs decSpec2)

Returns the dequantizer parameters. Dequantizer parameters normally are the quantization step sizes, see DequantizerParams.

Parameters:

src - The source of data for the dequantizer.

rb - The number of range bits for each component. Must be the number of range bits of the mixed components.

decSpec2 - The DecoderSpecs instance after any image manipulation.

Returns:

The dequantizer

getCbULX

public final int getCbULX()

Returns the horizontal code-block partition origin.Allowable values are 0 and 1, nothing else.

getCbULY

public final int getCbULY()

Returns the vertical code-block partition origin. Allowable values are 0 and 1, nothing else.

getPPX

public final int getPPX(int t,
                        int c,
                        int rl)

Returns the precinct partition width for the specified tile-component and resolution level.

Parameters:

c - the component index

t - the tile index

rl - the resolution level

Returns:

The precinct partition width for the specified tile-component and resolution level

getPPY

public final int getPPY(int t,
                        int c,
                        int rl)

Returns the precinct partition height for the specified tile-component and resolution level.

Parameters:

c - the component index

t - the tile index

rl - the resolution level

Returns:

The precinct partition height for the specified tile-component and resolution level

precinctPartitionUsed

public final boolean precinctPartitionUsed()

Returns the boolean used to know if the precinct partition is used

readFilter

private SynWTFilter readFilter(java.io.DataInputStream ehs,
                               int[] filtIdx)
                        throws java.io.IOException

Reads a wavelet filter from the codestream and returns the filter object that implements it.

Parameters:

ehs - The encoded header stream from where to read the info

filtIdx - Int array of one element to return the type of the wavelet filter.

java.io.IOException

checkMarkerLength

public void checkMarkerLength(java.io.DataInputStream ehs,
                              java.lang.String str)
                       throws java.io.IOException

Checks that the marker segment length is correct.

Parameters:

ehs - The encoded header stream

str - The string identifying the marker, such as "SIZ marker"

Throws:

java.io.IOException - If an I/O error occurs

readSIZ

private void readSIZ(java.io.DataInputStream ehs)
              throws java.io.IOException

Reads the SIZ marker segment and realigns the codestream at the point where the next marker segment should be found.

SIZ is a fixed information marker segment containing informations about image and tile sizes. It is required in the main header immediately after SOC.

Parameters:

ehs - The encoded header stream

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoded header stream

readCRG

private void readCRG(java.io.DataInputStream ehs)
              throws java.io.IOException

Reads a CRG marker segment and checks its length. CRG is an informational marker segment that allows specific registration of components with respect to each other.

Parameters:

ehs - The encoded header stream

java.io.IOException

readCOM

private void readCOM(java.io.DataInputStream ehs,
                     boolean mainh,
                     int tileIdx,
                     int comIdx)
              throws java.io.IOException

Reads a COM marker segments and realigns the bit stream at the point where the next marker segment should be found. COM is an informational marker segment that allows to include unstructured data in the main and tile-part headers.

Parameters:

ehs - The encoded header stream

mainh - Flag indicating whether or not this marker segment is read from the main header.

tileIdx - The index of the current tile

comIdx - Occurence of this COM marker in eith main or tile-part header

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoded header stream

readQCD

private void readQCD(java.io.DataInputStream ehs,
                     boolean mainh,
                     int tileIdx,
                     int tpIdx)
              throws java.io.IOException

Reads a QCD marker segment and realigns the codestream at the point where the next marker should be found. QCD is a functional marker segment that describes the quantization default.

Parameters:

ehs - The encoded stream.

mainh - Flag indicating whether or not this marker segment is read from the main header.

tileIdx - The index of the current tile

tpIdx - Tile-part index

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoded header stream.

readQCC

private void readQCC(java.io.DataInputStream ehs,
                     boolean mainh,
                     int tileIdx,
                     int tpIdx)
              throws java.io.IOException

Reads a QCC marker segment and realigns the codestream at the point where the next marker should be found. QCC is a functional marker segment that describes the quantization of one component.

Parameters:

ehs - The encoded stream.

mainh - Flag indicating whether or not this marker segment is read from the main header.

tileIdx - The index of the current tile

tpIdx - Tile-part index

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoded header stream.

readCOD

private void readCOD(java.io.DataInputStream ehs,
                     boolean mainh,
                     int tileIdx,
                     int tpIdx)
              throws java.io.IOException

Reads a COD marker segment and realigns the codestream where the next marker should be found.

Parameters:

ehs - The encoder header stream.

mainh - Flag indicating whether or not this marker segment is read from the main header.

tileIdx - The index of the current tile

tpIdx - Tile-part index

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoder header stream

readCOC

private void readCOC(java.io.DataInputStream ehs,
                     boolean mainh,
                     int tileIdx,
                     int tpIdx)
              throws java.io.IOException

Reads the COC marker segment and realigns the codestream where the next marker should be found.

Parameters:

ehs - The encoder header stream.

mainh - Flag indicating whether or not this marker segment is read from the main header.

tileIdx - The index of the current tile

tpIdx - Tile-part index

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoder header stream

readPOC

private void readPOC(java.io.DataInputStream ehs,
                     boolean mainh,
                     int t,
                     int tpIdx)
              throws java.io.IOException

Reads the POC marker segment and realigns the codestream where the next marker should be found.

Parameters:

ehs - The encoder header stream.

mainh - Flag indicating whether or not this marker segment is read from the main header.

t - The index of the current tile

tpIdx - Tile-part index

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoder header stream

readTLM

private void readTLM(java.io.DataInputStream ehs)
              throws java.io.IOException

Reads TLM marker segment and realigns the codestream where the next marker should be found. Informations stored in these fields are currently NOT taken into account.

Parameters:

ehs - The encoder header stream.

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoder header stream

readPLM

private void readPLM(java.io.DataInputStream ehs)
              throws java.io.IOException

Reads PLM marker segment and realigns the codestream where the next marker should be found. Informations stored in these fields are currently not taken into account.

Parameters:

ehs - The encoder header stream.

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoder header stream

readPLTFields

private void readPLTFields(java.io.DataInputStream ehs)
                    throws java.io.IOException

Reads the PLT fields and realigns the codestream where the next marker should be found. Informations stored in these fields are currently NOT taken into account.

Parameters:

ehs - The encoder header stream.

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoder header stream

readRGN

private void readRGN(java.io.DataInputStream ehs,
                     boolean mainh,
                     int tileIdx,
                     int tpIdx)
              throws java.io.IOException

Reads the RGN marker segment of the codestream header.

May be used in tile or main header. If used in main header, it refers to the maxshift value of a component in all tiles. When used in tile header, only the particular tile-component is affected.

Parameters:

ehs - The encoder header stream.

mainh - Flag indicating whether or not this marker segment is read from the main header.

tileIdx - The index of the current tile

tpIdx - Tile-part index

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoder header stream

readPPM

private void readPPM(java.io.DataInputStream ehs)
              throws java.io.IOException

Reads the PPM marker segment of the main header.

Parameters:

ehs - The encoder header stream.

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoder header stream

readPPT

private void readPPT(java.io.DataInputStream ehs,
                     int tile,
                     int tpIdx)
              throws java.io.IOException

Reads the PPT marker segment of the main header.

Parameters:

ehs - The encoder header stream.

tile - The tile to which the current tile part belongs

tpIdx - Tile-part index

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoder header stream

extractMainMarkSeg

private void extractMainMarkSeg(short marker,
                                RandomAccessIO ehs)
                         throws java.io.IOException

This method extract a marker segment from the main header and stores it into a byte buffer for the second pass. The marker segment is first identified. Then its flag is activated. Finally, its content is buffered into a byte array stored in an hashTable.

If the marker is not recognized, it prints a warning and skips it according to its length.

SIZ marker segment shall be the first encountered marker segment.

Parameters:

marker - The marker segment to process

ehs - The encoded header stream

java.io.IOException

extractTilePartMarkSeg

public void extractTilePartMarkSeg(short marker,
                                   RandomAccessIO ehs,
                                   int tileIdx,
                                   int tilePartIdx)
                            throws java.io.IOException

This method extracts a marker segment in a tile-part header and stores it into a byte buffer for the second pass. The marker is first recognized, then its flag is activated and, finally, its content is buffered in an element of byte arrays accessible thanks to a hashTable. If a marker segment is not recognized, it prints a warning and skip it according to its length.

Parameters:

marker - The marker to process

ehs - The encoded header stream

tileIdx - The index of the current tile

tilePartIdx - The index of the current tile part

java.io.IOException

readFoundMainMarkSeg

private void readFoundMainMarkSeg()
                           throws java.io.IOException

Retrieves and reads all marker segments found in the main header during the first pass.

java.io.IOException

readFoundTilePartMarkSeg

public void readFoundTilePartMarkSeg(int tileIdx,
                                     int tpIdx)
                              throws java.io.IOException

Retrieves and reads all marker segments previously found in the tile-part header.

Parameters:

tileIdx - The index of the current tile

tpIdx - Index of the current tile-part

java.io.IOException

getDecoderSpecs

public DecoderSpecs getDecoderSpecs()

Return the DecoderSpecs instance filled when reading the headers

Returns:

The DecoderSpecs of the decoder

createEntropyDecoder

public EntropyDecoder createEntropyDecoder(CodedCBlkDataSrcDec src,
                                           ParameterList pl)

Creates and returns the entropy decoder corresponding to the information read from the codestream header and with the special additional parameters from the parameter list.

Parameters:

src - The bit stream reader agent where to get code-block data from.

pl - The parameter list containing parameters applicable to the entropy decoder (other parameters can also be present).

Returns:

The entropy decoder

createColorSpaceMapper

public BlkImgDataSrc createColorSpaceMapper(BlkImgDataSrc src,
                                            ColorSpace csMap)
                                     throws java.io.IOException,
                                            ICCProfileException,
                                            ColorSpaceException

Creates and returns the EnumeratedColorSpaceMapper corresponding to the information read from the JP2 image file via the ColorSpace parameter.

Parameters:

src - The bit stream reader agent where to get code-block data from.

csMap - provides color space information from the image file

Returns:

The color space mapping object

Throws:

java.io.IOException - image access exception

ICCProfileException - if image contains a bad icc profile

ColorSpaceException - if image contains a bad colorspace box

createChannelDefinitionMapper

public BlkImgDataSrc createChannelDefinitionMapper(BlkImgDataSrc src,
                                                   ColorSpace csMap)
                                            throws java.io.IOException,
                                                   ColorSpaceException

Creates and returns the ChannelDefinitonMapper which maps the input channels to the channel definition for the appropriate colorspace.

Parameters:

src - The bit stream reader agent where to get code-block data from.

csMap - provides color space information from the image file

Returns:

The channel definition mapping object

Throws:

java.io.IOException - image access exception

ColorSpaceException - if image contains a bad colorspace box

createPalettizedColorSpaceMapper

public BlkImgDataSrc createPalettizedColorSpaceMapper(BlkImgDataSrc src,
                                                      ColorSpace csMap)
                                               throws java.io.IOException,
                                                      ColorSpaceException

Creates and returns the PalettizedColorSpaceMapper which uses the input samples as indicies into a sample palette to construct the output.

Parameters:

src - The bit stream reader agent where to get code-block data from.

csMap - provides color space information from the image file

Returns:

a PalettizedColorSpaceMapper instance

Throws:

java.io.IOException - image access exception

ColorSpaceException - if image contains a bad colorspace box

createResampler

public BlkImgDataSrc createResampler(BlkImgDataSrc src,
                                     ColorSpace csMap)
                              throws java.io.IOException,
                                     ColorSpaceException

Creates and returns the Resampler which converts the input source to one in which all channels have the same number of samples. This is required for colorspace conversions.

Parameters:

src - The bit stream reader agent where to get code-block data from.

csMap - provides color space information from the image file

Returns:

The resampled BlkImgDataSrc

Throws:

java.io.IOException - image access exception

ColorSpaceException - if image contains a bad colorspace box

createROIDeScaler

public ROIDeScaler createROIDeScaler(CBlkQuantDataSrcDec src,
                                     ParameterList pl,
                                     DecoderSpecs decSpec2)

Creates and returns the ROIDeScaler corresponding to the information read from the codestream header and with the special additional parameters from the parameter list.

Parameters:

src - The bit stream reader agent where to get code-block data from.

pl - The parameter list containing parameters applicable to the entropy decoder (other parameters can also be present).

decSpec2 - The DecoderSpecs instance after any image manipulation.

Returns:

The ROI descaler.

resetHeaderMarkers

public void resetHeaderMarkers()

Method that resets members indicating which markers have already been found

toString

public java.lang.String toString()

Print information about the current header.

Overrides:

toString in class java.lang.Object

Returns:

Information in a String

getParameterInfo

public static java.lang.String[][] getParameterInfo()

Returns the parameters that are used in this class. 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.

Returns:

the options name, their synopsis and their explanation.

getNumTiles

public int getNumTiles()

Return the number of tiles in the image

Returns:

The number of tiles

getPackedPktHead

public java.io.ByteArrayInputStream getPackedPktHead(int tile)
                                              throws java.io.IOException

Return the packed packet headers for a given tile.

Returns:

An input stream containing the packed packet headers for a particular tile

Throws:

java.io.IOException - If an I/O error occurs while reading from the encoder header stream

setTileOfTileParts

public void setTileOfTileParts(int tile)

Sets the tile of each tile part in order. This information is needed for identifying which packet header belongs to which tile when using the PPM marker.

Parameters:

tile - The tile number that the present tile part belongs to.

getNumFoundMarkSeg

public int getNumFoundMarkSeg()

Returns the number of found marker segments in the current header.

Returns:

The number of marker segments found in the current header.