org.dcm4che3.imageio.codec

Class Compressor

java.lang.Object

org.dcm4che3.imageio.codec.Compressor

All Implemented Interfaces:

Closeable, AutoCloseable

public class Compressor
extends Object
implements Closeable

Compresses the pixel data of DICOM images to a lossless or lossy encapsulated transfer syntax format.

If the source image is already compressed it will be transcoded (i.e. first decompressed then compressed again).

Author:

Gunter Zeilinger , Hermann Czedik-Eysenberg

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	Compressor.CacheOutputStream
private class	Compressor.CompressedFrame

Field Summary

Fields

Modifier and Type	Field and Description
private int	avgPixelValueBlockSize
private ImageWriter	compressor
private ImageWriteParam	compressParam
private PatchJPEGLS	compressPatchJPEGLS
private String	compressTsuid
private Attributes	dataset
private BufferedImage	decompressedImageForVerification
private Decompressor	decompressor
private int[]	embeddedOverlays
private IOException	ex
private ImageInputStream	iis
private ImageParams	imageParams
private static Logger	LOG
private int	maxPixelValueError
private VR.Holder	pixeldataVR
private Object	pixels
private TransferSyntaxType	tsType
private BufferedImage	uncompressedImage
private ImageReader	verifier
private ImageReadParam	verifyParam

Constructor Summary

Constructors

Constructor and Description
Compressor(Attributes dataset, String tsuid, String compressTsuid, Property... compressParams)

Method Summary

Modifier and Type	Method and Description
private Property[]	cat(Property[] a, Property[] b)
void	close()
boolean	compress()
ImageInputStream	createImageInputStream(int frameIndex)
void	dispose()
private void	extractEmbeddedOverlays(int frameIndex, BufferedImage bi)
long	getEstimatedNeededMemory()
private boolean	needToExtractEmbeddedOverlays()
BufferedImage	readFrame(int frameIndex)
private void	readFully(short[] data)
private void	verify(ImageInputStream iis, int index)

Methods inherited from class java.lang.Object

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

Field Detail

LOG

private static final Logger LOG

dataset

private final Attributes dataset

compressTsuid

private final String compressTsuid

pixels

private Object pixels

pixeldataVR

private VR.Holder pixeldataVR

tsType

private final TransferSyntaxType tsType

compressor

private ImageWriter compressor

verifier

private ImageReader verifier

compressPatchJPEGLS

private PatchJPEGLS compressPatchJPEGLS

compressParam

private ImageWriteParam compressParam

iis

private ImageInputStream iis

ex

private IOException ex

embeddedOverlays

private int[] embeddedOverlays

maxPixelValueError

private int maxPixelValueError

avgPixelValueBlockSize

private int avgPixelValueBlockSize

decompressedImageForVerification

private BufferedImage decompressedImageForVerification

imageParams

private ImageParams imageParams

decompressor

private Decompressor decompressor

uncompressedImage

private BufferedImage uncompressedImage

verifyParam

private ImageReadParam verifyParam

Constructor Detail

Compressor

public Compressor(Attributes dataset,
                  String tsuid,
                  String compressTsuid,
                  Property... compressParams)

Method Detail

compress

public boolean compress()
                 throws IOException

Throws:

IOException

needToExtractEmbeddedOverlays

private boolean needToExtractEmbeddedOverlays()

cat

private Property[] cat(Property[] a,
                       Property[] b)

close

public void close()

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

dispose

public void dispose()

readFrame

public BufferedImage readFrame(int frameIndex)
                        throws IOException

Throws:

IOException

verify

private void verify(ImageInputStream iis,
                    int index)
             throws IOException

Throws:

IOException

extractEmbeddedOverlays

private void extractEmbeddedOverlays(int frameIndex,
                                     BufferedImage bi)

readFully

private void readFully(short[] data)
                throws IOException

Throws:

IOException

createImageInputStream

public ImageInputStream createImageInputStream(int frameIndex)
                                        throws IOException

Throws:

IOException

getEstimatedNeededMemory

public long getEstimatedNeededMemory()

Returns:

(Pessimistic) estimation of the maximum heap memory (in bytes) that will be needed at any moment in time during compression.