Package gov.nih.mipav.model.file

Class MetadataExtractor.GifReader

java.lang.Object

gov.nih.mipav.model.file.MetadataExtractor.GifReader

Enclosing class:

MetadataExtractor

public class MetadataExtractor.GifReader
extends Object

Reader of GIF encoded data. Resources:

• https://wiki.whatwg.org/wiki/GIF
• https://www.w3.org/Graphics/GIF/spec-gif89a.txt
• http://web.archive.org/web/20100929230301/http://www.etsimo.uniovi.es/gifanim/gif87a.txt

Author:

Drew Noakes https://drewnoakes.com, Kevin Mott https://github.com/kwhopper

Field Summary

Fields

Modifier and Type	Field	Description
private static final String	GIF_87A_VERSION_IDENTIFIER
private static final String	GIF_89A_VERSION_IDENTIFIER

Constructor Summary

Constructors

Constructor	Description
GifReader()

Method Summary

Modifier and Type	Method	Description
void	extract(MetadataExtractor.SequentialReader reader, MetadataExtractor.Metadata metadata)
private byte[]	gatherBytes(MetadataExtractor.SequentialReader reader)
private byte[]	gatherBytes(MetadataExtractor.SequentialReader reader, int firstLength)
private void	readApplicationExtensionBlock(MetadataExtractor.SequentialReader reader, int blockSizeBytes, MetadataExtractor.Metadata metadata)
private MetadataExtractor.GifCommentDirectory	readCommentBlock(MetadataExtractor.SequentialReader reader, int blockSizeBytes)
private MetadataExtractor.GifControlDirectory	readControlBlock(MetadataExtractor.SequentialReader reader)
private void	readGifExtensionBlock(MetadataExtractor.SequentialReader reader, MetadataExtractor.Metadata metadata)
private MetadataExtractor.GifHeaderDirectory	readGifHeader(MetadataExtractor.SequentialReader reader)
private MetadataExtractor.GifImageDirectory	readImageBlock(MetadataExtractor.SequentialReader reader)
private MetadataExtractor.Directory	readPlainTextBlock(MetadataExtractor.SequentialReader reader, int blockSizeBytes)
private void	skipBlocks(MetadataExtractor.SequentialReader reader)

Methods inherited from class java.lang.Object

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

Field Details

GIF_87A_VERSION_IDENTIFIER

private static final String GIF_87A_VERSION_IDENTIFIER

See Also:

• Constant Field Values

GIF_89A_VERSION_IDENTIFIER

private static final String GIF_89A_VERSION_IDENTIFIER

See Also:

• Constant Field Values

Constructor Details

GifReader

public GifReader()

Method Details

extract

public void extract(MetadataExtractor.SequentialReader reader,
 MetadataExtractor.Metadata metadata)

readGifHeader

private MetadataExtractor.GifHeaderDirectory readGifHeader(MetadataExtractor.SequentialReader reader)
                                                    throws IOException

Throws:

IOException

readGifExtensionBlock

private void readGifExtensionBlock(MetadataExtractor.SequentialReader reader,
 MetadataExtractor.Metadata metadata)
                            throws IOException

Throws:

IOException

readPlainTextBlock

private MetadataExtractor.Directory readPlainTextBlock(MetadataExtractor.SequentialReader reader,
 int blockSizeBytes)
                                                throws IOException

Throws:

IOException

readCommentBlock

private MetadataExtractor.GifCommentDirectory readCommentBlock(MetadataExtractor.SequentialReader reader,
 int blockSizeBytes)
                                                        throws IOException

Throws:

IOException

readApplicationExtensionBlock

private void readApplicationExtensionBlock(MetadataExtractor.SequentialReader reader,
 int blockSizeBytes,
 MetadataExtractor.Metadata metadata)
                                    throws IOException

Throws:

IOException

readControlBlock

private MetadataExtractor.GifControlDirectory readControlBlock(MetadataExtractor.SequentialReader reader)
                                                        throws IOException

Throws:

IOException

readImageBlock

private MetadataExtractor.GifImageDirectory readImageBlock(MetadataExtractor.SequentialReader reader)
                                                    throws IOException

Throws:

IOException

gatherBytes

private byte[] gatherBytes(MetadataExtractor.SequentialReader reader)
                    throws IOException

Throws:

IOException

gatherBytes

private byte[] gatherBytes(MetadataExtractor.SequentialReader reader,
 int firstLength)
                    throws IOException

Throws:

IOException

skipBlocks

private void skipBlocks(MetadataExtractor.SequentialReader reader)
                 throws IOException

Throws:

IOException