jj2000.j2k.util

Class CodestreamManipulator

java.lang.Object

jj2000.j2k.util.CodestreamManipulator

public class CodestreamManipulator
extends Object

This class takes a legal JPEG 2000 codestream and performs some manipulation on it. Currently the manipulations supported are: Tile-parts

Field Summary

Fields

Modifier and Type	Field and Description
private File	file The name of the outfile
private byte[]	mainHeader The main header
private static int	MAX_TPSOT The maximum number of a tile part index (TPsot)
private int	maxtp The maximum number of tile parts in any tile
private int	nt The number of tiles in the image
private byte[][][]	packetData Buffers containing the packet data
private byte[][][]	packetHeaders Buffers contaning the packet headers
private Integer[]	positions The positions of the SOT, SOP and EPH markers
private boolean	ppmUsed Flag indicating whether packed packet headers in main header is used
private int[]	ppt The number of packets per tile
private int	pptp The number of packets per tile-part
private boolean	pptUsed Flag indicating whether packed packet headers in tile headers is used
private byte[][][]	sopMarkSeg Buffers containing the SOP marker segments
private boolean	tempEph Flag indicating whether EPH marker was only intended for parsing in This class and should be removed
private boolean	tempSop Flag indicating whether SOP marker was only intended for parsing in This class and should be removed
private byte[][]	tileHeaders Buffers containing the original tile headers
private byte[][][]	tileParts Buffers containing the tile parts
private static int	TP_HEAD_LEN The length of a SOT plus a SOD marker

Constructor Summary

Constructors

Constructor and Description
CodestreamManipulator(File file, int nt, int pptp, boolean ppm, boolean ppt, boolean tempSop, boolean tempEph) Instantiates a codestream manipulator..

Method Summary

Modifier and Type	Method and Description
private void	createTileParts() This method creates the tileparts from the buffered tile headers, packet headers and packet data
int	doCodestreamManipulation() This method performs the actual manipulation of the codestream which is the reparsing for tile parts and packed packet headers
private void	parseAndFind(BufferedRandomAccessFile fi) This method parses the codestream for SOT, SOP and EPH markers and removes header header bits signalling SOP and EPH markers if packed packet headers are used
private void	readAndBuffer(BufferedRandomAccessFile fi) This method reads and buffers the tile headers, packet headers and packet data.
private void	writeNewCodestream(BufferedRandomAccessFile fi) This method writes the new codestream to the file.

Methods inherited from class java.lang.Object

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

Field Detail

ppmUsed

private boolean ppmUsed

Flag indicating whether packed packet headers in main header is used

pptUsed

private boolean pptUsed

Flag indicating whether packed packet headers in tile headers is used

tempSop

private boolean tempSop

Flag indicating whether SOP marker was only intended for parsing in This class and should be removed

tempEph

private boolean tempEph

Flag indicating whether EPH marker was only intended for parsing in This class and should be removed

nt

private int nt

The number of tiles in the image

pptp

private int pptp

The number of packets per tile-part

file

private File file

The name of the outfile

TP_HEAD_LEN

private static int TP_HEAD_LEN

The length of a SOT plus a SOD marker

MAX_TPSOT

private static int MAX_TPSOT

The maximum number of a tile part index (TPsot)

maxtp

private int maxtp

The maximum number of tile parts in any tile

ppt

private int[] ppt

The number of packets per tile

positions

private Integer[] positions

The positions of the SOT, SOP and EPH markers

mainHeader

private byte[] mainHeader

The main header

tileParts

private byte[][][] tileParts

Buffers containing the tile parts

tileHeaders

private byte[][] tileHeaders

Buffers containing the original tile headers

packetHeaders

private byte[][][] packetHeaders

Buffers contaning the packet headers

packetData

private byte[][][] packetData

Buffers containing the packet data

sopMarkSeg

private byte[][][] sopMarkSeg

Buffers containing the SOP marker segments

Constructor Detail

CodestreamManipulator

public CodestreamManipulator(File file,
                             int nt,
                             int pptp,
                             boolean ppm,
                             boolean ppt,
                             boolean tempSop,
                             boolean tempEph)

Instantiates a codestream manipulator..

Parameters:

file - The name of the original outfile

nt - The number of tiles in the image

pptp - Packets per tile-part. If zero, no division into tileparts is performed

ppm - Flag indicating that PPM marker is used

ppt - Flag indicating that PPT marker is used

tempSop - Flag indicating whether SOP merker should be removed

tempEph - Flag indicating whether EPH merker should be removed

Method Detail

doCodestreamManipulation

public int doCodestreamManipulation()
                             throws IOException

This method performs the actual manipulation of the codestream which is the reparsing for tile parts and packed packet headers

Returns:

The number of bytes that the file has increased by

Throws:

IOException - If an I/O error ocurred.

parseAndFind

private void parseAndFind(BufferedRandomAccessFile fi)
                   throws IOException

This method parses the codestream for SOT, SOP and EPH markers and removes header header bits signalling SOP and EPH markers if packed packet headers are used

Parameters:

fi - The file to parse the markers from

Throws:

IOException - If an I/O error ocurred.

readAndBuffer

private void readAndBuffer(BufferedRandomAccessFile fi)
                    throws IOException

This method reads and buffers the tile headers, packet headers and packet data.

Parameters:

fi - The file to read the headers and data from

Throws:

IOException - If an I/O error ocurred.

createTileParts

private void createTileParts()
                      throws IOException

This method creates the tileparts from the buffered tile headers, packet headers and packet data

Throws:

IOException - If an I/O error ocurred.

writeNewCodestream

private void writeNewCodestream(BufferedRandomAccessFile fi)
                         throws IOException

This method writes the new codestream to the file.

Parameters:

fi - The file to write the new codestream to

Throws:

IOException - If an I/O error ocurred.