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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* published by the Free Software Foundation. Oracle designates this
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* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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*
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package com.sun.imageio.plugins.jpeg;
import javax.imageio.IIOException;
import javax.imageio.ImageWriter;
import javax.imageio.ImageWriteParam;
import javax.imageio.IIOImage;
import javax.imageio.ImageTypeSpecifier;
import javax.imageio.metadata.IIOMetadata;
import javax.imageio.metadata.IIOMetadataFormatImpl;
import javax.imageio.metadata.IIOInvalidTreeException;
import javax.imageio.spi.ImageWriterSpi;
import javax.imageio.stream.ImageOutputStream;
import javax.imageio.plugins.jpeg.JPEGImageWriteParam;
import javax.imageio.plugins.jpeg.JPEGQTable;
import javax.imageio.plugins.jpeg.JPEGHuffmanTable;
import org.w3c.dom.Node;
import java.awt.image.Raster;
import java.awt.image.WritableRaster;
import java.awt.image.SampleModel;
import java.awt.image.DataBuffer;
import java.awt.image.DataBufferByte;
import java.awt.image.ColorModel;
import java.awt.image.IndexColorModel;
import java.awt.image.ColorConvertOp;
import java.awt.image.RenderedImage;
import java.awt.image.BufferedImage;
import java.awt.color.ColorSpace;
import java.awt.color.ICC_ColorSpace;
import java.awt.color.ICC_Profile;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.Transparency;
import java.io.IOException;
import java.util.List;
import java.util.ArrayList;
import java.util.Iterator;
import sun.java2d.Disposer;
import sun.java2d.DisposerRecord;
public class JPEGImageWriter extends ImageWriter {
///////// Private variables
private boolean debug = false;
/**
* The following variable contains a pointer to the IJG library
* structure for this reader. It is assigned in the constructor
* and then is passed in to every native call. It is set to 0
* by dispose to avoid disposing twice.
*/
private long structPointer = 0;
/** The output stream we write to */
private ImageOutputStream ios = null;
/** The Raster we will write from */
private Raster srcRas = null;
/** An intermediate Raster holding compressor-friendly data */
private WritableRaster raster = null;
/**
* Set to true if we are writing an image with an
* indexed ColorModel
*/
private boolean indexed = false;
private IndexColorModel indexCM = null;
private boolean convertTosRGB = false; // Used by PhotoYCC only
private WritableRaster converted = null;
private boolean isAlphaPremultiplied = false;
private ColorModel srcCM = null;
/**
* If there are thumbnails to be written, this is the list.
*/
private List thumbnails = null;
/**
* If metadata should include an icc profile, store it here.
*/
private ICC_Profile iccProfile = null;
private int sourceXOffset = 0;
private int sourceYOffset = 0;
private int sourceWidth = 0;
private int [] srcBands = null;
private int sourceHeight = 0;
/** Used when calling listeners */
private int currentImage = 0;
private ColorConvertOp convertOp = null;
private JPEGQTable [] streamQTables = null;
private JPEGHuffmanTable[] streamDCHuffmanTables = null;
private JPEGHuffmanTable[] streamACHuffmanTables = null;
// Parameters for writing metadata
private boolean ignoreJFIF = false; // If it's there, use it
private boolean forceJFIF = false; // Add one for the thumbnails
private boolean ignoreAdobe = false; // If it's there, use it
private int newAdobeTransform = JPEG.ADOBE_IMPOSSIBLE; // Change if needed
private boolean writeDefaultJFIF = false;
private boolean writeAdobe = false;
private JPEGMetadata metadata = null;
private boolean sequencePrepared = false;
private int numScans = 0;
/** The referent to be registered with the Disposer. */
private Object disposerReferent = new Object();
/** The DisposerRecord that handles the actual disposal of this writer. */
private DisposerRecord disposerRecord;
///////// End of Private variables
///////// Protected variables
protected static final int WARNING_DEST_IGNORED = 0;
protected static final int WARNING_STREAM_METADATA_IGNORED = 1;
protected static final int WARNING_DEST_METADATA_COMP_MISMATCH = 2;
protected static final int WARNING_DEST_METADATA_JFIF_MISMATCH = 3;
protected static final int WARNING_DEST_METADATA_ADOBE_MISMATCH = 4;
protected static final int WARNING_IMAGE_METADATA_JFIF_MISMATCH = 5;
protected static final int WARNING_IMAGE_METADATA_ADOBE_MISMATCH = 6;
protected static final int WARNING_METADATA_NOT_JPEG_FOR_RASTER = 7;
protected static final int WARNING_NO_BANDS_ON_INDEXED = 8;
protected static final int WARNING_ILLEGAL_THUMBNAIL = 9;
protected static final int WARNING_IGNORING_THUMBS = 10;
protected static final int WARNING_FORCING_JFIF = 11;
protected static final int WARNING_THUMB_CLIPPED = 12;
protected static final int WARNING_METADATA_ADJUSTED_FOR_THUMB = 13;
protected static final int WARNING_NO_RGB_THUMB_AS_INDEXED = 14;
protected static final int WARNING_NO_GRAY_THUMB_AS_INDEXED = 15;
private static final int MAX_WARNING = WARNING_NO_GRAY_THUMB_AS_INDEXED;
///////// End of Protected variables
///////// static initializer
static {
java.security.AccessController.doPrivileged(
new java.security.PrivilegedAction<Void>() {
public Void run() {
System.loadLibrary("jpeg");
return null;
}
});
initWriterIDs(JPEGQTable.class,
JPEGHuffmanTable.class);
}
//////// Public API
public JPEGImageWriter(ImageWriterSpi originator) {
super(originator);
structPointer = initJPEGImageWriter();
disposerRecord = new JPEGWriterDisposerRecord(structPointer);
Disposer.addRecord(disposerReferent, disposerRecord);
}
public void setOutput(Object output) {
setThreadLock();
try {
cbLock.check();
super.setOutput(output); // validates output
resetInternalState();
ios = (ImageOutputStream) output; // so this will always work
// Set the native destination
setDest(structPointer);
} finally {
clearThreadLock();
}
}
public ImageWriteParam getDefaultWriteParam() {
return new JPEGImageWriteParam(null);
}
public IIOMetadata getDefaultStreamMetadata(ImageWriteParam param) {
setThreadLock();
try {
return new JPEGMetadata(param, this);
} finally {
clearThreadLock();
}
}
public IIOMetadata
getDefaultImageMetadata(ImageTypeSpecifier imageType,
ImageWriteParam param) {
setThreadLock();
try {
return new JPEGMetadata(imageType, param, this);
} finally {
clearThreadLock();
}
}
public IIOMetadata convertStreamMetadata(IIOMetadata inData,
ImageWriteParam param) {
// There isn't much we can do. If it's one of ours, then
// return it. Otherwise just return null. We use it only
// for tables, so we can't get a default and modify it,
// as this will usually not be what is intended.
if (inData instanceof JPEGMetadata) {
JPEGMetadata jpegData = (JPEGMetadata) inData;
if (jpegData.isStream) {
return inData;
}
}
return null;
}
public IIOMetadata
convertImageMetadata(IIOMetadata inData,
ImageTypeSpecifier imageType,
ImageWriteParam param) {
setThreadLock();
try {
return convertImageMetadataOnThread(inData, imageType, param);
} finally {
clearThreadLock();
}
}
private IIOMetadata
convertImageMetadataOnThread(IIOMetadata inData,
ImageTypeSpecifier imageType,
ImageWriteParam param) {
// If it's one of ours, just return it
if (inData instanceof JPEGMetadata) {
JPEGMetadata jpegData = (JPEGMetadata) inData;
if (!jpegData.isStream) {
return inData;
} else {
// Can't convert stream metadata to image metadata
// XXX Maybe this should put out a warning?
return null;
}
}
// If it's not one of ours, create a default and set it from
// the standard tree from the input, if it exists.
if (inData.isStandardMetadataFormatSupported()) {
String formatName =
IIOMetadataFormatImpl.standardMetadataFormatName;
Node tree = inData.getAsTree(formatName);
if (tree != null) {
JPEGMetadata jpegData = new JPEGMetadata(imageType,
param,
this);
try {
jpegData.setFromTree(formatName, tree);
} catch (IIOInvalidTreeException e) {
// Other plug-in generates bogus standard tree
// XXX Maybe this should put out a warning?
return null;
}
return jpegData;
}
}
return null;
}
public int getNumThumbnailsSupported(ImageTypeSpecifier imageType,
ImageWriteParam param,
IIOMetadata streamMetadata,
IIOMetadata imageMetadata) {
if (jfifOK(imageType, param, streamMetadata, imageMetadata)) {
return Integer.MAX_VALUE;
}
return 0;
}
static final Dimension [] preferredThumbSizes = {new Dimension(1, 1),
new Dimension(255, 255)};
public Dimension[] getPreferredThumbnailSizes(ImageTypeSpecifier imageType,
ImageWriteParam param,
IIOMetadata streamMetadata,
IIOMetadata imageMetadata) {
if (jfifOK(imageType, param, streamMetadata, imageMetadata)) {
return (Dimension [])preferredThumbSizes.clone();
}
return null;
}
private boolean jfifOK(ImageTypeSpecifier imageType,
ImageWriteParam param,
IIOMetadata streamMetadata,
IIOMetadata imageMetadata) {
// If the image type and metadata are JFIF compatible, return true
if ((imageType != null) &&
(!JPEG.isJFIFcompliant(imageType, true))) {
return false;
}
if (imageMetadata != null) {
JPEGMetadata metadata = null;
if (imageMetadata instanceof JPEGMetadata) {
metadata = (JPEGMetadata) imageMetadata;
} else {
metadata = (JPEGMetadata)convertImageMetadata(imageMetadata,
imageType,
param);
}
// metadata must have a jfif node
if (metadata.findMarkerSegment
(JFIFMarkerSegment.class, true) == null){
return false;
}
}
return true;
}
public boolean canWriteRasters() {
return true;
}
public void write(IIOMetadata streamMetadata,
IIOImage image,
ImageWriteParam param) throws IOException {
setThreadLock();
try {
cbLock.check();
writeOnThread(streamMetadata, image, param);
} finally {
clearThreadLock();
}
}
private void writeOnThread(IIOMetadata streamMetadata,
IIOImage image,
ImageWriteParam param) throws IOException {
if (ios == null) {
throw new IllegalStateException("Output has not been set!");
}
if (image == null) {
throw new IllegalArgumentException("image is null!");
}
// if streamMetadata is not null, issue a warning
if (streamMetadata != null) {
warningOccurred(WARNING_STREAM_METADATA_IGNORED);
}
// Obtain the raster and image, if there is one
boolean rasterOnly = image.hasRaster();
RenderedImage rimage = null;
if (rasterOnly) {
srcRas = image.getRaster();
} else {
rimage = image.getRenderedImage();
if (rimage instanceof BufferedImage) {
// Use the Raster directly.
srcRas = ((BufferedImage)rimage).getRaster();
} else if (rimage.getNumXTiles() == 1 &&
rimage.getNumYTiles() == 1)
{
// Get the unique tile.
srcRas = rimage.getTile(rimage.getMinTileX(),
rimage.getMinTileY());
// Ensure the Raster has dimensions of the image,
// as the tile dimensions might differ.
if (srcRas.getWidth() != rimage.getWidth() ||
srcRas.getHeight() != rimage.getHeight())
{
srcRas = srcRas.createChild(srcRas.getMinX(),
srcRas.getMinY(),
rimage.getWidth(),
rimage.getHeight(),
srcRas.getMinX(),
srcRas.getMinY(),
null);
}
} else {
// Image is tiled so get a contiguous raster by copying.
srcRas = rimage.getData();
}
}
// Now determine if we are using a band subset
// By default, we are using all source bands
int numSrcBands = srcRas.getNumBands();
indexed = false;
indexCM = null;
ColorModel cm = null;
ColorSpace cs = null;
isAlphaPremultiplied = false;
srcCM = null;
if (!rasterOnly) {
cm = rimage.getColorModel();
if (cm != null) {
cs = cm.getColorSpace();
if (cm instanceof IndexColorModel) {
indexed = true;
indexCM = (IndexColorModel) cm;
numSrcBands = cm.getNumComponents();
}
if (cm.isAlphaPremultiplied()) {
isAlphaPremultiplied = true;
srcCM = cm;
}
}
}
srcBands = JPEG.bandOffsets[numSrcBands-1];
int numBandsUsed = numSrcBands;
// Consult the param to determine if we're writing a subset
if (param != null) {
int[] sBands = param.getSourceBands();
if (sBands != null) {
if (indexed) {
warningOccurred(WARNING_NO_BANDS_ON_INDEXED);
} else {
srcBands = sBands;
numBandsUsed = srcBands.length;
if (numBandsUsed > numSrcBands) {
throw new IIOException
("ImageWriteParam specifies too many source bands");
}
}
}
}
boolean usingBandSubset = (numBandsUsed != numSrcBands);
boolean fullImage = ((!rasterOnly) && (!usingBandSubset));
int [] bandSizes = null;
if (!indexed) {
bandSizes = srcRas.getSampleModel().getSampleSize();
// If this is a subset, we must adjust bandSizes
if (usingBandSubset) {
int [] temp = new int [numBandsUsed];
for (int i = 0; i < numBandsUsed; i++) {
temp[i] = bandSizes[srcBands[i]];
}
bandSizes = temp;
}
} else {
int [] tempSize = srcRas.getSampleModel().getSampleSize();
bandSizes = new int [numSrcBands];
for (int i = 0; i < numSrcBands; i++) {
bandSizes[i] = tempSize[0]; // All the same
}
}
for (int i = 0; i < bandSizes.length; i++) {
// 4450894 part 1: The IJG libraries are compiled so they only
// handle <= 8-bit samples. We now check the band sizes and throw
// an exception for images, such as USHORT_GRAY, with > 8 bits
// per sample.
if (bandSizes[i] <= 0 || bandSizes[i] > 8) {
throw new IIOException("Illegal band size: should be 0 < size <= 8");
}
// 4450894 part 2: We expand IndexColorModel images to full 24-
// or 32-bit in grabPixels() for each scanline. For indexed
// images such as BYTE_BINARY, we need to ensure that we update
// bandSizes to account for the scaling from 1-bit band sizes
// to 8-bit.
if (indexed) {
bandSizes[i] = 8;
}
}
if (debug) {
System.out.println("numSrcBands is " + numSrcBands);
System.out.println("numBandsUsed is " + numBandsUsed);
System.out.println("usingBandSubset is " + usingBandSubset);
System.out.println("fullImage is " + fullImage);
System.out.print("Band sizes:");
for (int i = 0; i< bandSizes.length; i++) {
System.out.print(" " + bandSizes[i]);
}
System.out.println();
}
// Destination type, if there is one
ImageTypeSpecifier destType = null;
if (param != null) {
destType = param.getDestinationType();
// Ignore dest type if we are writing a complete image
if ((fullImage) && (destType != null)) {
warningOccurred(WARNING_DEST_IGNORED);
destType = null;
}
}
// Examine the param
sourceXOffset = srcRas.getMinX();
sourceYOffset = srcRas.getMinY();
int imageWidth = srcRas.getWidth();
int imageHeight = srcRas.getHeight();
sourceWidth = imageWidth;
sourceHeight = imageHeight;
int periodX = 1;
int periodY = 1;
int gridX = 0;
int gridY = 0;
JPEGQTable [] qTables = null;
JPEGHuffmanTable[] DCHuffmanTables = null;
JPEGHuffmanTable[] ACHuffmanTables = null;
boolean optimizeHuffman = false;
JPEGImageWriteParam jparam = null;
int progressiveMode = ImageWriteParam.MODE_DISABLED;
if (param != null) {
Rectangle sourceRegion = param.getSourceRegion();
if (sourceRegion != null) {
Rectangle imageBounds = new Rectangle(sourceXOffset,
sourceYOffset,
sourceWidth,
sourceHeight);
sourceRegion = sourceRegion.intersection(imageBounds);
sourceXOffset = sourceRegion.x;
sourceYOffset = sourceRegion.y;
sourceWidth = sourceRegion.width;
sourceHeight = sourceRegion.height;
}
if (sourceWidth + sourceXOffset > imageWidth) {
sourceWidth = imageWidth - sourceXOffset;
}
if (sourceHeight + sourceYOffset > imageHeight) {
sourceHeight = imageHeight - sourceYOffset;
}
periodX = param.getSourceXSubsampling();
periodY = param.getSourceYSubsampling();
gridX = param.getSubsamplingXOffset();
gridY = param.getSubsamplingYOffset();
switch(param.getCompressionMode()) {
case ImageWriteParam.MODE_DISABLED:
throw new IIOException("JPEG compression cannot be disabled");
case ImageWriteParam.MODE_EXPLICIT:
float quality = param.getCompressionQuality();
quality = JPEG.convertToLinearQuality(quality);
qTables = new JPEGQTable[2];
qTables[0] = JPEGQTable.K1Luminance.getScaledInstance
(quality, true);
qTables[1] = JPEGQTable.K2Chrominance.getScaledInstance
(quality, true);
break;
case ImageWriteParam.MODE_DEFAULT:
qTables = new JPEGQTable[2];
qTables[0] = JPEGQTable.K1Div2Luminance;
qTables[1] = JPEGQTable.K2Div2Chrominance;
break;
// We'll handle the metadata case later
}
progressiveMode = param.getProgressiveMode();
if (param instanceof JPEGImageWriteParam) {
jparam = (JPEGImageWriteParam)param;
optimizeHuffman = jparam.getOptimizeHuffmanTables();
}
}
// Now examine the metadata
IIOMetadata mdata = image.getMetadata();
if (mdata != null) {
if (mdata instanceof JPEGMetadata) {
metadata = (JPEGMetadata) mdata;
if (debug) {
System.out.println
("We have metadata, and it's JPEG metadata");
}
} else {
if (!rasterOnly) {
ImageTypeSpecifier type = destType;
if (type == null) {
type = new ImageTypeSpecifier(rimage);
}
metadata = (JPEGMetadata) convertImageMetadata(mdata,
type,
param);
} else {
warningOccurred(WARNING_METADATA_NOT_JPEG_FOR_RASTER);
}
}
}
// First set a default state
ignoreJFIF = false; // If it's there, use it
ignoreAdobe = false; // If it's there, use it
newAdobeTransform = JPEG.ADOBE_IMPOSSIBLE; // Change if needed
writeDefaultJFIF = false;
writeAdobe = false;
// By default we'll do no conversion:
int inCsType = JPEG.JCS_UNKNOWN;
int outCsType = JPEG.JCS_UNKNOWN;
JFIFMarkerSegment jfif = null;
AdobeMarkerSegment adobe = null;
SOFMarkerSegment sof = null;
if (metadata != null) {
jfif = (JFIFMarkerSegment) metadata.findMarkerSegment
(JFIFMarkerSegment.class, true);
adobe = (AdobeMarkerSegment) metadata.findMarkerSegment
(AdobeMarkerSegment.class, true);
sof = (SOFMarkerSegment) metadata.findMarkerSegment
(SOFMarkerSegment.class, true);
}
iccProfile = null; // By default don't write one
convertTosRGB = false; // PhotoYCC does this
converted = null;
if (destType != null) {
if (numBandsUsed != destType.getNumBands()) {
throw new IIOException
("Number of source bands != number of destination bands");
}
cs = destType.getColorModel().getColorSpace();
// Check the metadata against the destination type
if (metadata != null) {
checkSOFBands(sof, numBandsUsed);
checkJFIF(jfif, destType, false);
// Do we want to write an ICC profile?
if ((jfif != null) && (ignoreJFIF == false)) {
if (JPEG.isNonStandardICC(cs)) {
iccProfile = ((ICC_ColorSpace) cs).getProfile();
}
}
checkAdobe(adobe, destType, false);
} else { // no metadata, but there is a dest type
// If we can add a JFIF or an Adobe marker segment, do so
if (JPEG.isJFIFcompliant(destType, false)) {
writeDefaultJFIF = true;
// Do we want to write an ICC profile?
if (JPEG.isNonStandardICC(cs)) {
iccProfile = ((ICC_ColorSpace) cs).getProfile();
}
} else {
int transform = JPEG.transformForType(destType, false);
if (transform != JPEG.ADOBE_IMPOSSIBLE) {
writeAdobe = true;
newAdobeTransform = transform;
}
}
// re-create the metadata
metadata = new JPEGMetadata(destType, null, this);
}
inCsType = getSrcCSType(destType);
outCsType = getDefaultDestCSType(destType);
} else { // no destination type
if (metadata == null) {
if (fullImage) { // no dest, no metadata, full image
// Use default metadata matching the image and param
metadata = new JPEGMetadata(new ImageTypeSpecifier(rimage),
param, this);
if (metadata.findMarkerSegment
(JFIFMarkerSegment.class, true) != null) {
cs = rimage.getColorModel().getColorSpace();
if (JPEG.isNonStandardICC(cs)) {
iccProfile = ((ICC_ColorSpace) cs).getProfile();
}
}
inCsType = getSrcCSType(rimage);
outCsType = getDefaultDestCSType(rimage);
}
// else no dest, no metadata, not an image,
// so no special headers, no color conversion
} else { // no dest type, but there is metadata
checkSOFBands(sof, numBandsUsed);
if (fullImage) { // no dest, metadata, image
// Check that the metadata and the image match
ImageTypeSpecifier inputType =
new ImageTypeSpecifier(rimage);
inCsType = getSrcCSType(rimage);
if (cm != null) {
boolean alpha = cm.hasAlpha();
switch (cs.getType()) {
case ColorSpace.TYPE_GRAY:
if (!alpha) {
outCsType = JPEG.JCS_GRAYSCALE;
} else {
if (jfif != null) {
ignoreJFIF = true;
warningOccurred
(WARNING_IMAGE_METADATA_JFIF_MISMATCH);
}
// out colorspace remains unknown
}
if ((adobe != null)
&& (adobe.transform != JPEG.ADOBE_UNKNOWN)) {
newAdobeTransform = JPEG.ADOBE_UNKNOWN;
warningOccurred
(WARNING_IMAGE_METADATA_ADOBE_MISMATCH);
}
break;
case ColorSpace.TYPE_RGB:
if (!alpha) {
if (jfif != null) {
outCsType = JPEG.JCS_YCbCr;
if (JPEG.isNonStandardICC(cs)
|| ((cs instanceof ICC_ColorSpace)
&& (jfif.iccSegment != null))) {
iccProfile =
((ICC_ColorSpace) cs).getProfile();
}
} else if (adobe != null) {
switch (adobe.transform) {
case JPEG.ADOBE_UNKNOWN:
outCsType = JPEG.JCS_RGB;
break;
case JPEG.ADOBE_YCC:
outCsType = JPEG.JCS_YCbCr;
break;
default:
warningOccurred
(WARNING_IMAGE_METADATA_ADOBE_MISMATCH);
newAdobeTransform = JPEG.ADOBE_UNKNOWN;
outCsType = JPEG.JCS_RGB;
break;
}
} else {
// consult the ids
int outCS = sof.getIDencodedCSType();
// if they don't resolve it,
// consult the sampling factors
if (outCS != JPEG.JCS_UNKNOWN) {
outCsType = outCS;
} else {
boolean subsampled =
isSubsampled(sof.componentSpecs);
if (subsampled) {
outCsType = JPEG.JCS_YCbCr;
} else {
outCsType = JPEG.JCS_RGB;
}
}
}
} else { // RGBA
if (jfif != null) {
ignoreJFIF = true;
warningOccurred
(WARNING_IMAGE_METADATA_JFIF_MISMATCH);
}
if (adobe != null) {
if (adobe.transform
!= JPEG.ADOBE_UNKNOWN) {
newAdobeTransform = JPEG.ADOBE_UNKNOWN;
warningOccurred
(WARNING_IMAGE_METADATA_ADOBE_MISMATCH);
}
outCsType = JPEG.JCS_RGBA;
} else {
// consult the ids
int outCS = sof.getIDencodedCSType();
// if they don't resolve it,
// consult the sampling factors
if (outCS != JPEG.JCS_UNKNOWN) {
outCsType = outCS;
} else {
boolean subsampled =
isSubsampled(sof.componentSpecs);
outCsType = subsampled ?
JPEG.JCS_YCbCrA : JPEG.JCS_RGBA;
}
}
}
break;
case ColorSpace.TYPE_3CLR:
if (cs == JPEG.JCS.getYCC()) {
if (!alpha) {
if (jfif != null) {
convertTosRGB = true;
convertOp =
new ColorConvertOp(cs,
JPEG.JCS.sRGB,
null);
outCsType = JPEG.JCS_YCbCr;
} else if (adobe != null) {
if (adobe.transform
!= JPEG.ADOBE_YCC) {
newAdobeTransform = JPEG.ADOBE_YCC;
warningOccurred
(WARNING_IMAGE_METADATA_ADOBE_MISMATCH);
}
outCsType = JPEG.JCS_YCC;
} else {
outCsType = JPEG.JCS_YCC;
}
} else { // PhotoYCCA
if (jfif != null) {
ignoreJFIF = true;
warningOccurred
(WARNING_IMAGE_METADATA_JFIF_MISMATCH);
} else if (adobe != null) {
if (adobe.transform
!= JPEG.ADOBE_UNKNOWN) {
newAdobeTransform
= JPEG.ADOBE_UNKNOWN;
warningOccurred
(WARNING_IMAGE_METADATA_ADOBE_MISMATCH);
}
}
outCsType = JPEG.JCS_YCCA;
}
}
}
}
} // else no dest, metadata, not an image. Defaults ok
}
}
boolean metadataProgressive = false;
int [] scans = null;
if (metadata != null) {
if (sof == null) {
sof = (SOFMarkerSegment) metadata.findMarkerSegment
(SOFMarkerSegment.class, true);
}
if ((sof != null) && (sof.tag == JPEG.SOF2)) {
metadataProgressive = true;
if (progressiveMode == ImageWriteParam.MODE_COPY_FROM_METADATA) {
scans = collectScans(metadata, sof); // Might still be null
} else {
numScans = 0;
}
}
if (jfif == null) {
jfif = (JFIFMarkerSegment) metadata.findMarkerSegment
(JFIFMarkerSegment.class, true);
}
}
thumbnails = image.getThumbnails();
int numThumbs = image.getNumThumbnails();
forceJFIF = false;
// determine if thumbnails can be written
// If we are going to add a default JFIF marker segment,
// then thumbnails can be written
if (!writeDefaultJFIF) {
// If there is no metadata, then we can't write thumbnails
if (metadata == null) {
thumbnails = null;
if (numThumbs != 0) {
warningOccurred(WARNING_IGNORING_THUMBS);
}
} else {
// There is metadata
// If we are writing a raster or subbands,
// then the user must specify JFIF on the metadata
if (fullImage == false) {
if (jfif == null) {
thumbnails = null; // Or we can't include thumbnails
if (numThumbs != 0) {
warningOccurred(WARNING_IGNORING_THUMBS);
}
}
} else { // It is a full image, and there is metadata
if (jfif == null) { // Not JFIF
// Can it have JFIF?
if ((outCsType == JPEG.JCS_GRAYSCALE)
|| (outCsType == JPEG.JCS_YCbCr)) {
if (numThumbs != 0) {
forceJFIF = true;
warningOccurred(WARNING_FORCING_JFIF);
}
} else { // Nope, not JFIF-compatible
thumbnails = null;
if (numThumbs != 0) {
warningOccurred(WARNING_IGNORING_THUMBS);
}
}
}
}
}
}
// Set up a boolean to indicate whether we need to call back to
// write metadata
boolean haveMetadata =
((metadata != null) || writeDefaultJFIF || writeAdobe);
// Now that we have dealt with metadata, finalize our tables set up
// Are we going to write tables? By default, yes.
boolean writeDQT = true;
boolean writeDHT = true;
// But if the metadata has no tables, no.
DQTMarkerSegment dqt = null;
DHTMarkerSegment dht = null;
int restartInterval = 0;
if (metadata != null) {
dqt = (DQTMarkerSegment) metadata.findMarkerSegment
(DQTMarkerSegment.class, true);
dht = (DHTMarkerSegment) metadata.findMarkerSegment
(DHTMarkerSegment.class, true);
DRIMarkerSegment dri =
(DRIMarkerSegment) metadata.findMarkerSegment
(DRIMarkerSegment.class, true);
if (dri != null) {
restartInterval = dri.restartInterval;
}
if (dqt == null) {
writeDQT = false;
}
if (dht == null) {
writeDHT = false; // Ignored if optimizeHuffman is true
}
}
// Whether we write tables or not, we need to figure out which ones
// to use
if (qTables == null) { // Get them from metadata, or use defaults
if (dqt != null) {
qTables = collectQTablesFromMetadata(metadata);
} else if (streamQTables != null) {
qTables = streamQTables;
} else if ((jparam != null) && (jparam.areTablesSet())) {
qTables = jparam.getQTables();
} else {
qTables = JPEG.getDefaultQTables();
}
}
// If we are optimizing, we don't want any tables.
if (optimizeHuffman == false) {
// If they were for progressive scans, we can't use them.
if ((dht != null) && (metadataProgressive == false)) {
DCHuffmanTables = collectHTablesFromMetadata(metadata, true);
ACHuffmanTables = collectHTablesFromMetadata(metadata, false);
} else if (streamDCHuffmanTables != null) {
DCHuffmanTables = streamDCHuffmanTables;
ACHuffmanTables = streamACHuffmanTables;
} else if ((jparam != null) && (jparam.areTablesSet())) {
DCHuffmanTables = jparam.getDCHuffmanTables();
ACHuffmanTables = jparam.getACHuffmanTables();
} else {
DCHuffmanTables = JPEG.getDefaultHuffmanTables(true);
ACHuffmanTables = JPEG.getDefaultHuffmanTables(false);
}
}
// By default, ids are 1 - N, no subsampling
int [] componentIds = new int[numBandsUsed];
int [] HsamplingFactors = new int[numBandsUsed];
int [] VsamplingFactors = new int[numBandsUsed];
int [] QtableSelectors = new int[numBandsUsed];
for (int i = 0; i < numBandsUsed; i++) {
componentIds[i] = i+1; // JFIF compatible
HsamplingFactors[i] = 1;
VsamplingFactors[i] = 1;
QtableSelectors[i] = 0;
}
// Now override them with the contents of sof, if there is one,
if (sof != null) {
for (int i = 0; i < numBandsUsed; i++) {
if (forceJFIF == false) { // else use JFIF-compatible default
componentIds[i] = sof.componentSpecs[i].componentId;
}
HsamplingFactors[i] = sof.componentSpecs[i].HsamplingFactor;
VsamplingFactors[i] = sof.componentSpecs[i].VsamplingFactor;
QtableSelectors[i] = sof.componentSpecs[i].QtableSelector;
}
}
sourceXOffset += gridX;
sourceWidth -= gridX;
sourceYOffset += gridY;
sourceHeight -= gridY;
int destWidth = (sourceWidth + periodX - 1)/periodX;
int destHeight = (sourceHeight + periodY - 1)/periodY;
// Create an appropriate 1-line databuffer for writing
int lineSize = sourceWidth*numBandsUsed;
DataBufferByte buffer = new DataBufferByte(lineSize);
// Create a raster from that
int [] bandOffs = JPEG.bandOffsets[numBandsUsed-1];
raster = Raster.createInterleavedRaster(buffer,
sourceWidth, 1,
lineSize,
numBandsUsed,
bandOffs,
null);
// Call the writer, who will call back for every scanline
processImageStarted(currentImage);
boolean aborted = false;
if (debug) {
System.out.println("inCsType: " + inCsType);
System.out.println("outCsType: " + outCsType);
}
// Note that getData disables acceleration on buffer, but it is
// just a 1-line intermediate data transfer buffer that does not
// affect the acceleration of the source image.
aborted = writeImage(structPointer,
buffer.getData(),
inCsType, outCsType,
numBandsUsed,
bandSizes,
sourceWidth,
destWidth, destHeight,
periodX, periodY,
qTables,
writeDQT,
DCHuffmanTables,
ACHuffmanTables,
writeDHT,
optimizeHuffman,
(progressiveMode
!= ImageWriteParam.MODE_DISABLED),
numScans,
scans,
componentIds,
HsamplingFactors,
VsamplingFactors,
QtableSelectors,
haveMetadata,
restartInterval);
cbLock.lock();
try {
if (aborted) {
processWriteAborted();
} else {
processImageComplete();
}
ios.flush();
} finally {
cbLock.unlock();
}
currentImage++; // After a successful write
}
public void prepareWriteSequence(IIOMetadata streamMetadata)
throws IOException {
setThreadLock();
try {
cbLock.check();
prepareWriteSequenceOnThread(streamMetadata);
} finally {
clearThreadLock();
}
}
private void prepareWriteSequenceOnThread(IIOMetadata streamMetadata)
throws IOException {
if (ios == null) {
throw new IllegalStateException("Output has not been set!");
}
/*
* from jpeg_metadata.html:
* If no stream metadata is supplied to
* <code>ImageWriter.prepareWriteSequence</code>, then no
* tables-only image is written. If stream metadata containing
* no tables is supplied to
* <code>ImageWriter.prepareWriteSequence</code>, then a tables-only
* image containing default visually lossless tables is written.
*/
if (streamMetadata != null) {
if (streamMetadata instanceof JPEGMetadata) {
// write a complete tables-only image at the beginning of
// the stream.
JPEGMetadata jmeta = (JPEGMetadata) streamMetadata;
if (jmeta.isStream == false) {
throw new IllegalArgumentException
("Invalid stream metadata object.");
}
// Check that we are
// at the beginning of the stream, or can go there, and haven't
// written out the metadata already.
if (currentImage != 0) {
throw new IIOException
("JPEG Stream metadata must precede all images");
}
if (sequencePrepared == true) {
throw new IIOException("Stream metadata already written!");
}
// Set the tables
// If the metadata has no tables, use default tables.
streamQTables = collectQTablesFromMetadata(jmeta);
if (debug) {
System.out.println("after collecting from stream metadata, "
+ "streamQTables.length is "
+ streamQTables.length);
}
if (streamQTables == null) {
streamQTables = JPEG.getDefaultQTables();
}
streamDCHuffmanTables =
collectHTablesFromMetadata(jmeta, true);
if (streamDCHuffmanTables == null) {
streamDCHuffmanTables = JPEG.getDefaultHuffmanTables(true);
}
streamACHuffmanTables =
collectHTablesFromMetadata(jmeta, false);
if (streamACHuffmanTables == null) {
streamACHuffmanTables = JPEG.getDefaultHuffmanTables(false);
}
// Now write them out
writeTables(structPointer,
streamQTables,
streamDCHuffmanTables,
streamACHuffmanTables);
} else {
throw new IIOException("Stream metadata must be JPEG metadata");
}
}
sequencePrepared = true;
}
public void writeToSequence(IIOImage image, ImageWriteParam param)
throws IOException {
setThreadLock();
try {
cbLock.check();
if (sequencePrepared == false) {
throw new IllegalStateException("sequencePrepared not called!");
}
// In the case of JPEG this does nothing different from write
write(null, image, param);
} finally {
clearThreadLock();
}
}
public void endWriteSequence() throws IOException {
setThreadLock();
try {
cbLock.check();
if (sequencePrepared == false) {
throw new IllegalStateException("sequencePrepared not called!");
}
sequencePrepared = false;
} finally {
clearThreadLock();
}
}
public synchronized void abort() {
setThreadLock();
try {
/**
* NB: we do not check the call back lock here, we allow to abort
* the reader any time.
*/
super.abort();
abortWrite(structPointer);
} finally {
clearThreadLock();
}
}
private void resetInternalState() {
// reset C structures
resetWriter(structPointer);
// reset local Java structures
srcRas = null;
raster = null;
convertTosRGB = false;
currentImage = 0;
numScans = 0;
metadata = null;
}
public void reset() {
setThreadLock();
try {
cbLock.check();
super.reset();
} finally {
clearThreadLock();
}
}
public void dispose() {
setThreadLock();
try {
cbLock.check();
if (structPointer != 0) {
disposerRecord.dispose();
structPointer = 0;
}
} finally {
clearThreadLock();
}
}
////////// End of public API
///////// Package-access API
/**
* Called by the native code or other classes to signal a warning.
* The code is used to lookup a localized message to be used when
* sending warnings to listeners.
*/
void warningOccurred(int code) {
cbLock.lock();
try {
if ((code < 0) || (code > MAX_WARNING)){
throw new InternalError("Invalid warning index");
}
processWarningOccurred
(currentImage,
"com.sun.imageio.plugins.jpeg.JPEGImageWriterResources",
Integer.toString(code));
} finally {
cbLock.unlock();
}
}
/**
* The library has it's own error facility that emits warning messages.
* This routine is called by the native code when it has already
* formatted a string for output.
* XXX For truly complete localization of all warning messages,
* the sun_jpeg_output_message routine in the native code should
* send only the codes and parameters to a method here in Java,
* which will then format and send the warnings, using localized
* strings. This method will have to deal with all the parameters
* and formats (%u with possibly large numbers, %02d, %02x, etc.)
* that actually occur in the JPEG library. For now, this prevents
* library warnings from being printed to stderr.
*/
void warningWithMessage(String msg) {
cbLock.lock();
try {
processWarningOccurred(currentImage, msg);
} finally {
cbLock.unlock();
}
}
void thumbnailStarted(int thumbnailIndex) {
cbLock.lock();
try {
processThumbnailStarted(currentImage, thumbnailIndex);
} finally {
cbLock.unlock();
}
}
// Provide access to protected superclass method
void thumbnailProgress(float percentageDone) {
cbLock.lock();
try {
processThumbnailProgress(percentageDone);
} finally {
cbLock.unlock();
}
}
// Provide access to protected superclass method
void thumbnailComplete() {
cbLock.lock();
try {
processThumbnailComplete();
} finally {
cbLock.unlock();
}
}
///////// End of Package-access API
///////// Private methods
///////// Metadata handling
private void checkSOFBands(SOFMarkerSegment sof, int numBandsUsed)
throws IIOException {
// Does the metadata frame header, if any, match numBandsUsed?
if (sof != null) {
if (sof.componentSpecs.length != numBandsUsed) {
throw new IIOException
("Metadata components != number of destination bands");
}
}
}
private void checkJFIF(JFIFMarkerSegment jfif,
ImageTypeSpecifier type,
boolean input) {
if (jfif != null) {
if (!JPEG.isJFIFcompliant(type, input)) {
ignoreJFIF = true; // type overrides metadata
warningOccurred(input
? WARNING_IMAGE_METADATA_JFIF_MISMATCH
: WARNING_DEST_METADATA_JFIF_MISMATCH);
}
}
}
private void checkAdobe(AdobeMarkerSegment adobe,
ImageTypeSpecifier type,
boolean input) {
if (adobe != null) {
int rightTransform = JPEG.transformForType(type, input);
if (adobe.transform != rightTransform) {
warningOccurred(input
? WARNING_IMAGE_METADATA_ADOBE_MISMATCH
: WARNING_DEST_METADATA_ADOBE_MISMATCH);
if (rightTransform == JPEG.ADOBE_IMPOSSIBLE) {
ignoreAdobe = true;
} else {
newAdobeTransform = rightTransform;
}
}
}
}
/**
* Collect all the scan info from the given metadata, and
* organize it into the scan info array required by the
* IJG libray. It is much simpler to parse out this
* data in Java and then just copy the data in C.
*/
private int [] collectScans(JPEGMetadata metadata,
SOFMarkerSegment sof) {
List segments = new ArrayList();
int SCAN_SIZE = 9;
int MAX_COMPS_PER_SCAN = 4;
for (Iterator iter = metadata.markerSequence.iterator();
iter.hasNext();) {
MarkerSegment seg = (MarkerSegment) iter.next();
if (seg instanceof SOSMarkerSegment) {
segments.add(seg);
}
}
int [] retval = null;
numScans = 0;
if (!segments.isEmpty()) {
numScans = segments.size();
retval = new int [numScans*SCAN_SIZE];
int index = 0;
for (int i = 0; i < numScans; i++) {
SOSMarkerSegment sos = (SOSMarkerSegment) segments.get(i);
retval[index++] = sos.componentSpecs.length; // num comps
for (int j = 0; j < MAX_COMPS_PER_SCAN; j++) {
if (j < sos.componentSpecs.length) {
int compSel = sos.componentSpecs[j].componentSelector;
for (int k = 0; k < sof.componentSpecs.length; k++) {
if (compSel == sof.componentSpecs[k].componentId) {
retval[index++] = k;
break; // out of for over sof comps
}
}
} else {
retval[index++] = 0;
}
}
retval[index++] = sos.startSpectralSelection;
retval[index++] = sos.endSpectralSelection;
retval[index++] = sos.approxHigh;
retval[index++] = sos.approxLow;
}
}
return retval;
}
/**
* Finds all DQT marker segments and returns all the q
* tables as a single array of JPEGQTables.
*/
private JPEGQTable [] collectQTablesFromMetadata
(JPEGMetadata metadata) {
ArrayList tables = new ArrayList();
Iterator iter = metadata.markerSequence.iterator();
while (iter.hasNext()) {
MarkerSegment seg = (MarkerSegment) iter.next();
if (seg instanceof DQTMarkerSegment) {
DQTMarkerSegment dqt =
(DQTMarkerSegment) seg;
tables.addAll(dqt.tables);
}
}
JPEGQTable [] retval = null;
if (tables.size() != 0) {
retval = new JPEGQTable[tables.size()];
for (int i = 0; i < retval.length; i++) {
retval[i] =
new JPEGQTable(((DQTMarkerSegment.Qtable)tables.get(i)).data);
}
}
return retval;
}
/**
* Finds all DHT marker segments and returns all the q
* tables as a single array of JPEGQTables. The metadata
* must not be for a progressive image, or an exception
* will be thrown when two Huffman tables with the same
* table id are encountered.
*/
private JPEGHuffmanTable[] collectHTablesFromMetadata
(JPEGMetadata metadata, boolean wantDC) throws IIOException {
ArrayList tables = new ArrayList();
Iterator iter = metadata.markerSequence.iterator();
while (iter.hasNext()) {
MarkerSegment seg = (MarkerSegment) iter.next();
if (seg instanceof DHTMarkerSegment) {
DHTMarkerSegment dht =
(DHTMarkerSegment) seg;
for (int i = 0; i < dht.tables.size(); i++) {
DHTMarkerSegment.Htable htable =
(DHTMarkerSegment.Htable) dht.tables.get(i);
if (htable.tableClass == (wantDC ? 0 : 1)) {
tables.add(htable);
}
}
}
}
JPEGHuffmanTable [] retval = null;
if (tables.size() != 0) {
DHTMarkerSegment.Htable [] htables =
new DHTMarkerSegment.Htable[tables.size()];
tables.toArray(htables);
retval = new JPEGHuffmanTable[tables.size()];
for (int i = 0; i < retval.length; i++) {
retval[i] = null;
for (int j = 0; j < tables.size(); j++) {
if (htables[j].tableID == i) {
if (retval[i] != null) {
throw new IIOException("Metadata has duplicate Htables!");
}
retval[i] = new JPEGHuffmanTable(htables[j].numCodes,
htables[j].values);
}
}
}
}
return retval;
}
/////////// End of metadata handling
////////////// ColorSpace conversion
private int getSrcCSType(ImageTypeSpecifier type) {
return getSrcCSType(type.getColorModel());
}
private int getSrcCSType(RenderedImage rimage) {
return getSrcCSType(rimage.getColorModel());
}
private int getSrcCSType(ColorModel cm) {
int retval = JPEG.JCS_UNKNOWN;
if (cm != null) {
boolean alpha = cm.hasAlpha();
ColorSpace cs = cm.getColorSpace();
switch (cs.getType()) {
case ColorSpace.TYPE_GRAY:
retval = JPEG.JCS_GRAYSCALE;
break;
case ColorSpace.TYPE_RGB:
if (alpha) {
retval = JPEG.JCS_RGBA;
} else {
retval = JPEG.JCS_RGB;
}
break;
case ColorSpace.TYPE_YCbCr:
if (alpha) {
retval = JPEG.JCS_YCbCrA;
} else {
retval = JPEG.JCS_YCbCr;
}
break;
case ColorSpace.TYPE_3CLR:
if (cs == JPEG.JCS.getYCC()) {
if (alpha) {
retval = JPEG.JCS_YCCA;
} else {
retval = JPEG.JCS_YCC;
}
}
case ColorSpace.TYPE_CMYK:
retval = JPEG.JCS_CMYK;
break;
}
}
return retval;
}
private int getDestCSType(ImageTypeSpecifier destType) {
ColorModel cm = destType.getColorModel();
boolean alpha = cm.hasAlpha();
ColorSpace cs = cm.getColorSpace();
int retval = JPEG.JCS_UNKNOWN;
switch (cs.getType()) {
case ColorSpace.TYPE_GRAY:
retval = JPEG.JCS_GRAYSCALE;
break;
case ColorSpace.TYPE_RGB:
if (alpha) {
retval = JPEG.JCS_RGBA;
} else {
retval = JPEG.JCS_RGB;
}
break;
case ColorSpace.TYPE_YCbCr:
if (alpha) {
retval = JPEG.JCS_YCbCrA;
} else {
retval = JPEG.JCS_YCbCr;
}
break;
case ColorSpace.TYPE_3CLR:
if (cs == JPEG.JCS.getYCC()) {
if (alpha) {
retval = JPEG.JCS_YCCA;
} else {
retval = JPEG.JCS_YCC;
}
}
case ColorSpace.TYPE_CMYK:
retval = JPEG.JCS_CMYK;
break;
}
return retval;
}
private int getDefaultDestCSType(ImageTypeSpecifier type) {
return getDefaultDestCSType(type.getColorModel());
}
private int getDefaultDestCSType(RenderedImage rimage) {
return getDefaultDestCSType(rimage.getColorModel());
}
private int getDefaultDestCSType(ColorModel cm) {
int retval = JPEG.JCS_UNKNOWN;
if (cm != null) {
boolean alpha = cm.hasAlpha();
ColorSpace cs = cm.getColorSpace();
switch (cs.getType()) {
case ColorSpace.TYPE_GRAY:
retval = JPEG.JCS_GRAYSCALE;
break;
case ColorSpace.TYPE_RGB:
if (alpha) {
retval = JPEG.JCS_YCbCrA;
} else {
retval = JPEG.JCS_YCbCr;
}
break;
case ColorSpace.TYPE_YCbCr:
if (alpha) {
retval = JPEG.JCS_YCbCrA;
} else {
retval = JPEG.JCS_YCbCr;
}
break;
case ColorSpace.TYPE_3CLR:
if (cs == JPEG.JCS.getYCC()) {
if (alpha) {
retval = JPEG.JCS_YCCA;
} else {
retval = JPEG.JCS_YCC;
}
}
case ColorSpace.TYPE_CMYK:
retval = JPEG.JCS_YCCK;
break;
}
}
return retval;
}
private boolean isSubsampled(SOFMarkerSegment.ComponentSpec [] specs) {
int hsamp0 = specs[0].HsamplingFactor;
int vsamp0 = specs[0].VsamplingFactor;
for (int i = 1; i < specs.length; i++) {
if ((specs[i].HsamplingFactor != hsamp0) ||
(specs[i].HsamplingFactor != hsamp0))
return true;
}
return false;
}
////////////// End of ColorSpace conversion
////////////// Native methods and callbacks
/** Sets up static native structures. */
private static native void initWriterIDs(Class qTableClass,
Class huffClass);
/** Sets up per-writer native structure and returns a pointer to it. */
private native long initJPEGImageWriter();
/** Sets up native structures for output stream */
private native void setDest(long structPointer);
/**
* Returns <code>true</code> if the write was aborted.
*/
private native boolean writeImage(long structPointer,
byte [] data,
int inCsType, int outCsType,
int numBands,
int [] bandSizes,
int srcWidth,
int destWidth, int destHeight,
int stepX, int stepY,
JPEGQTable [] qtables,
boolean writeDQT,
JPEGHuffmanTable[] DCHuffmanTables,
JPEGHuffmanTable[] ACHuffmanTables,
boolean writeDHT,
boolean optimizeHuffman,
boolean progressive,
int numScans,
int [] scans,
int [] componentIds,
int [] HsamplingFactors,
int [] VsamplingFactors,
int [] QtableSelectors,
boolean haveMetadata,
int restartInterval);
/**
* Writes the metadata out when called by the native code,
* which will have already written the header to the stream
* and established the library state. This is simpler than
* breaking the write call in two.
*/
private void writeMetadata() throws IOException {
if (metadata == null) {
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