edu.harvard.hul.ois.jhove.module.tiff
Class IFD

java.lang.Object
  edu.harvard.hul.ois.jhove.module.tiff.IFD

Direct Known Subclasses:

ExifIFD, GlobalParametersIFD, GPSInfoIFD, InteroperabilityIFD, TiffIFD

public abstract class IFD
extends java.lang.Object

Encapsulation of a TIFF image file directory (IFD).

Field Summary

protected boolean	_bigEndian True if big-endian file.
protected RepInfo	_info Representation information.
protected long	_next Offset of next IFD.
protected long	_offset IFD offset.
protected int	_version TIFF version.
static int	ASCII TIFF ASCII type.
static int	BYTE TIFF BYTE (unsigned 8-bit) type.
static int	DOUBLE TIFF DOUBLE (64-bit IEEE floating point) type.
static int	EXIF Exif IFD.
static int	FLOAT TIFF FLOAT (32-bit IEEE floating point) type.
static int	GLOBALPARAMETERS Global parameters IFD.
static int	GPSINFO GPSInfo IFD.
static int	IFD TIFF IFD (LONG) type.
static int	INTEROPERABILITY Exif Interoperability IFD.
static int	LONG TIFF LONG (unsigned 32-bit) type.
static int	NULL Undefined value for integer tags.
static int	RATIONAL TIFF RATIONAL (two LONGs) type.
static int	SBYTE TIFF SBYTE (signed 8-bit) type.
static int	SHORT TIFF SHORT (unsigned 16-bit) type.
static int	SLONG TIFF SLONG (signed 32-bit) type.
static int	SRATIONAL TIFF SRATIONAL (two SLONGs) type.
static int	SSHORT TIFF SSHORT (signed 16-bit) type.
static int	TIFF Standard TIFF IFD.
static java.lang.String[]	TYPE TIFF type labels.
static int	UNDEFINED TIFF UNDEFINED (unsigned 8-bit) type.

Constructor Summary

IFD(long offset, RepInfo info, java.io.RandomAccessFile raf, boolean bigEndian)
Instantiate an IFD object.

Method Summary

protected Property	addBitmaskProperty(java.lang.String name, long value, java.lang.String[] labels, boolean rawOutput) Returns a Property representing a bitmask.
protected Property	addIntegerArrayProperty(java.lang.String name, int[] value, java.lang.String[] labels, boolean rawOutput) Returns an ARRAY Property representing an integer array.
protected Property	addIntegerProperty(java.lang.String name, int value, java.lang.String[] labels, boolean rawOutput) Returns an Property representing an integer value.
protected Property	addIntegerProperty(java.lang.String name, int value, java.lang.String[] labels, int[] index, boolean rawOutput) Returns an Property representing an integer value.
protected Property	addRationalArrayProperty(java.lang.String name, Rational[] r, boolean rawOutput)
protected Property	addRationalProperty(java.lang.String name, Rational r, boolean rawOutput) Returns a property for a tag with a RATIONAL value.
protected static Rational	average(Rational r1, Rational r2)
static long	calcValueSize(int type, long count) Calculate how many bytes a given number of fields of a given type will require.
protected static void	checkCount(int tag, long count, int minCount) Check the tag entry count.
protected static void	checkType(int tag, int type, int expected) Check the tag entry type.
protected static void	checkType(int tag, int type, int type1, int type2) Check the tag entry type.
java.util.List<java.lang.String>	getErrors() Get any errors discovered during parsing.
long	getNext() Get the offset of the next IFD.
long	getOffset() Get the IFD offset.
abstract Property	getProperty(boolean rawOutput) Get the IFD properties.
int	getVersion() Get the TIFF version.
boolean	isBigEndian() Returns true if file is big-endian, false if little-endian.
boolean	isFirst() Return true if this is the first IFD.
boolean	isThumbnail() Return true if this is the thumbnail IFD.
abstract void	lookupTag(int tag, int type, long count, long value) Lookup IFD tag.
long	parse() Parse the IFD.
long	parse(boolean byteOffsetIsValid) Parse the IFD.
long	parse(boolean byteOffsetIsValid, boolean suppressErrors) Parse the IFD.
protected void	postParseInitialization() Perform initializations that have to wait until after the IFD has been parsed.
protected Property	propertyHeader(java.lang.String type, java.util.List entries) Standard IFD property header.
protected java.lang.String	readASCII(long count, long value) Reads a string value from the TIFF file.
protected java.lang.String[]	readASCIIArray(long count, long value) Reads an array of strings from the TIFF file.
protected int	readByte(int type, long count, long value) Reads and returns a single unsigned 8-bit integer value.
protected int[]	readByteArray(int type, long count, long value) Reads an array of bytes and returns it as an int array.
protected double[]	readDoubleArray(long count, long value) Reads a TIFF array of DOUBLE 64-bit values and returns it as a double array.
protected long	readLong(int type, long count, long value) Reads and returns a single unsigned 32-bit integer value.
protected long[]	readLongArray(int type, long count, long value) Reads a TIFF array of signed 32-bit integer values and returns it as a long array.
protected Rational	readRational(long count, long value) Reads a RATIONAL value and returns it as a Rational.
protected Rational[]	readRationalArray(long count, long value) Reads an array of RATIONAL values and returns it as an array of Rational.
protected int	readShort(int type, long count, long value) Reads and returns a single unsigned 16-bit value.
protected int[]	readShortArray(int type, long count, long value) Reads a TIFF array of unsigned 16-bit values and returns it as an int array.
protected Rational	readSignedRational(long count, long value) Reads an SRATIONAL value and returns it as a Rational.
protected Rational[]	readSignedRationalArray(long count, long value) Reads an array of SRATIONAL values and returns it as an array of Rational.
protected int[]	readSShortArray(int type, long count, long value) Reads a TIFF array of signed 16-bit values and returns it as an int array.
protected byte[]	readTrueByteArray(int type, long count, long value) Reads an array of bytes and returns it as a byte array.
long	readUnsigned(int type) Reads an unsigned number of any type.
void	setFirst(boolean first) Sets flag indicating whether this is the first IFD.
void	setThumbnail(boolean thumbnail) Sets flag indicating whether this is the "thumbnail" IFD.

Methods inherited from class java.lang.Object

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

Field Detail

TIFF

public static final int TIFF

Standard TIFF IFD.

See Also:

Constant Field Values

EXIF

public static final int EXIF

Exif IFD.

See Also:

Constant Field Values

INTEROPERABILITY

public static final int INTEROPERABILITY

Exif Interoperability IFD.

See Also:

Constant Field Values

GPSINFO

public static final int GPSINFO

GPSInfo IFD.

See Also:

Constant Field Values

GLOBALPARAMETERS

public static final int GLOBALPARAMETERS

Global parameters IFD.

See Also:

Constant Field Values

NULL

public static final int NULL

Undefined value for integer tags.

See Also:

Constant Field Values

BYTE

public static final int BYTE

TIFF BYTE (unsigned 8-bit) type.

See Also:

Constant Field Values

ASCII

public static final int ASCII

TIFF ASCII type.

See Also:

Constant Field Values

SHORT

public static final int SHORT

TIFF SHORT (unsigned 16-bit) type.

See Also:

Constant Field Values

LONG

public static final int LONG

TIFF LONG (unsigned 32-bit) type.

See Also:

Constant Field Values

RATIONAL

public static final int RATIONAL

TIFF RATIONAL (two LONGs) type.

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Constant Field Values

SBYTE

public static final int SBYTE

TIFF SBYTE (signed 8-bit) type.

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Constant Field Values

UNDEFINED

public static final int UNDEFINED

TIFF UNDEFINED (unsigned 8-bit) type.

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Constant Field Values

SSHORT

public static final int SSHORT

TIFF SSHORT (signed 16-bit) type.

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Constant Field Values

SLONG

public static final int SLONG

TIFF SLONG (signed 32-bit) type.

See Also:

Constant Field Values

SRATIONAL

public static final int SRATIONAL

TIFF SRATIONAL (two SLONGs) type.

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Constant Field Values

FLOAT

public static final int FLOAT

TIFF FLOAT (32-bit IEEE floating point) type.

See Also:

Constant Field Values

DOUBLE

public static final int DOUBLE

TIFF DOUBLE (64-bit IEEE floating point) type.

See Also:

Constant Field Values

IFD

public static final int IFD

TIFF IFD (LONG) type.

See Also:

Constant Field Values

TYPE

public static final java.lang.String[] TYPE

TIFF type labels.

_bigEndian

protected boolean _bigEndian

True if big-endian file.

_info

protected RepInfo _info

Representation information.

_next

protected long _next

Offset of next IFD.

_offset

protected long _offset

IFD offset.

_version

protected int _version

TIFF version.

Constructor Detail

IFD

public IFD(long offset,
           RepInfo info,
           java.io.RandomAccessFile raf,
           boolean bigEndian)

Instantiate an IFD object.

Parameters:

offset - IFD offset

info - Representation information

raf - TIFF file

bigEndian - True if big-endian file

Method Detail

getErrors

public java.util.List<java.lang.String> getErrors()

Get any errors discovered during parsing.

getNext

public long getNext()

Get the offset of the next IFD.

getOffset

public long getOffset()

Get the IFD offset.

getProperty

public abstract Property getProperty(boolean rawOutput)
                              throws TiffException

Get the IFD properties.

Throws:

TiffException

getVersion

public int getVersion()

Get the TIFF version.

isFirst

public boolean isFirst()

Return true if this is the first IFD.

isThumbnail

public boolean isThumbnail()

Return true if this is the thumbnail IFD.

lookupTag

public abstract void lookupTag(int tag,
                               int type,
                               long count,
                               long value)
                        throws TiffException

Lookup IFD tag.

Throws:

TiffException

parse

public long parse()
           throws TiffException

Parse the IFD. Errors are not suppressed, and odd byte offsets for tags not allowed.

Returns:

The offset of the next IFD

Throws:

TiffException

parse

public long parse(boolean byteOffsetIsValid,
                  boolean suppressErrors)
           throws TiffException

Parse the IFD.

Parameters:

byteOffsetIsValid - If true, allow offsets on odd byte boundaries

suppressErrors - If true, return IFD even with errors

Returns:

The offset of the next IFD

Throws:

TiffException

parse

public long parse(boolean byteOffsetIsValid)
           throws TiffException

Parse the IFD. Errors are not suppressed.

Parameters:

byteOffsetIsValid - If true, allow offsets on odd byte boundaries

Returns:

The offset of the next IFD

Throws:

TiffException

setFirst

public void setFirst(boolean first)

Sets flag indicating whether this is the first IFD.

setThumbnail

public void setThumbnail(boolean thumbnail)

Sets flag indicating whether this is the "thumbnail" IFD. The second IFD in the top-level chain is assumed to be the Thumbnail IFD.

addBitmaskProperty

protected Property addBitmaskProperty(java.lang.String name,
                                      long value,
                                      java.lang.String[] labels,
                                      boolean rawOutput)

Returns a Property representing a bitmask. If rawOutput is true, returns a LIST property whose elements are STRING properties. The string values of these STRING properties are the elements of labels whose indices correspond to 1 bits in the bitmask, counting the low-order bit as bit 0. if rawOutput is false, returns a LONG property whose numeric value is value.

addIntegerProperty

protected Property addIntegerProperty(java.lang.String name,
                                      int value,
                                      java.lang.String[] labels,
                                      boolean rawOutput)

Returns an Property representing an integer value. If rawOutput is true, returns an INTEGER property, and labels and index are unused. Otherwise, returns a STRING property, with the string being the element of labels whose index is value.

addIntegerProperty

protected Property addIntegerProperty(java.lang.String name,
                                      int value,
                                      java.lang.String[] labels,
                                      int[] index,
                                      boolean rawOutput)

Returns an Property representing an integer value. If rawOutput is true, returns an INTEGER property, and labels and index are unused. Otherwise, returns a STRING property, with the string being the element of labels whose index is the index of value in index.

addIntegerArrayProperty

protected Property addIntegerArrayProperty(java.lang.String name,
                                           int[] value,
                                           java.lang.String[] labels,
                                           boolean rawOutput)

Returns an ARRAY Property representing an integer array. If rawOutput is true, the elements of the property array are INTEGER properties, and labels is unused. Otherwise, the elements of the array are STRING properties, with the elements of value used as indices into labels.

addRationalProperty

protected Property addRationalProperty(java.lang.String name,
                                       Rational r,
                                       boolean rawOutput)

Returns a property for a tag with a RATIONAL value. If rawOutput is true, returns a property with type RATIONAL. Otherwise, returns a property with type STRING, and the text representation of the Rational value as a floating-point ratio.

addRationalArrayProperty

protected Property addRationalArrayProperty(java.lang.String name,
                                            Rational[] r,
                                            boolean rawOutput)

postParseInitialization

protected void postParseInitialization()

Perform initializations that have to wait until after the IFD has been parsed.

propertyHeader

protected Property propertyHeader(java.lang.String type,
                                  java.util.List entries)

Standard IFD property header.

readASCII

protected java.lang.String readASCII(long count,
                                     long value)
                              throws java.io.IOException

Reads a string value from the TIFF file. If there are non-ASCII characters, they're escaped as %XX

Parameters:

count - Length of string

value - Offset of string

Throws:

java.io.IOException

readASCIIArray

protected java.lang.String[] readASCIIArray(long count,
                                            long value)
                                     throws java.io.IOException

Reads an array of strings from the TIFF file.

Parameters:

count - Number of strings to read

value - Offset from which to read

Throws:

java.io.IOException

readByte

protected int readByte(int type,
                       long count,
                       long value)
                throws java.io.IOException

Reads and returns a single unsigned 8-bit integer value.

Parameters:

type - TIFF type to read; must be an 8-bit type

count - Unused

value - Offset from which to read

Throws:

java.io.IOException

readByteArray

protected int[] readByteArray(int type,
                              long count,
                              long value)
                       throws java.io.IOException

Reads an array of bytes and returns it as an int array.

Parameters:

type - TIFF type to read; must be an 8-bit type

count - Number of bytes to read

value - Offset from which to read

Throws:

java.io.IOException

readTrueByteArray

protected byte[] readTrueByteArray(int type,
                                   long count,
                                   long value)
                            throws java.io.IOException

Reads an array of bytes and returns it as a byte array.

Parameters:

type - Unused

count - Number of bytes to read

value - Offset from which to read

Throws:

java.io.IOException

readDoubleArray

protected double[] readDoubleArray(long count,
                                   long value)
                            throws java.io.IOException

Reads a TIFF array of DOUBLE 64-bit values and returns it as a double array.

Parameters:

count - Number of values to read

value - Offset from which to read

Throws:

java.io.IOException

readLong

protected long readLong(int type,
                        long count,
                        long value)
                 throws java.io.IOException

Reads and returns a single unsigned 32-bit integer value.

Parameters:

type - TIFF type to read; must be a 32-bit type

count - Unused

value - Offset from which to read

Throws:

java.io.IOException

readLongArray

protected long[] readLongArray(int type,
                               long count,
                               long value)
                        throws java.io.IOException

Reads a TIFF array of signed 32-bit integer values and returns it as a long array.

Parameters:

type - TIFF type to read; must be a 32-bit type

count - Number of values to read

value - Offset from which to read

Throws:

java.io.IOException

readUnsigned

public long readUnsigned(int type)
                  throws java.io.IOException

Reads an unsigned number of any type.

Parameters:

type - TIFF type to read

Throws:

java.io.IOException

readRational

protected Rational readRational(long count,
                                long value)
                         throws java.io.IOException

Reads a RATIONAL value and returns it as a Rational.

Throws:

java.io.IOException

readRationalArray

protected Rational[] readRationalArray(long count,
                                       long value)
                                throws java.io.IOException

Reads an array of RATIONAL values and returns it as an array of Rational.

Throws:

java.io.IOException

readSignedRational

protected Rational readSignedRational(long count,
                                      long value)
                               throws java.io.IOException

Reads an SRATIONAL value and returns it as a Rational.

Throws:

java.io.IOException

readSignedRationalArray

protected Rational[] readSignedRationalArray(long count,
                                             long value)
                                      throws java.io.IOException

Reads an array of SRATIONAL values and returns it as an array of Rational.

Throws:

java.io.IOException

readShort

protected int readShort(int type,
                        long count,
                        long value)
                 throws java.io.IOException

Reads and returns a single unsigned 16-bit value.

Throws:

java.io.IOException

readShortArray

protected int[] readShortArray(int type,
                               long count,
                               long value)
                        throws java.io.IOException

Reads a TIFF array of unsigned 16-bit values and returns it as an int array.

Throws:

java.io.IOException

readSShortArray

protected int[] readSShortArray(int type,
                                long count,
                                long value)
                         throws java.io.IOException

Reads a TIFF array of signed 16-bit values and returns it as an int array.

Throws:

java.io.IOException

calcValueSize

public static long calcValueSize(int type,
                                 long count)

Calculate how many bytes a given number of fields of a given type will require.

Parameters:

type - Field type

count - Field count

isBigEndian

public boolean isBigEndian()

Returns true if file is big-endian, false if little-endian.

checkCount

protected static void checkCount(int tag,
                                 long count,
                                 int minCount)
                          throws TiffException

Check the tag entry count.

Parameters:

tag - Tag entry value

count - Tag entry count

minCount - Tag count

Throws:

TiffException

checkType

protected static void checkType(int tag,
                                int type,
                                int expected)
                         throws TiffException

Check the tag entry type.

Parameters:

tag - Tag entry value

type - Tag entry type

expected - Tag type

Throws:

TiffException

checkType

protected static void checkType(int tag,
                                int type,
                                int type1,
                                int type2)
                         throws TiffException

Check the tag entry type.

Parameters:

tag - Tag entry value

type - Tag entry type

type1 - Tag type

type2 - Alternate tag type

Throws:

TiffException

average

protected static Rational average(Rational r1,
                                  Rational r2)