src/com/android/gallery3d/exif/ExifOutputStream.java - LeafOS-Project/android_packages_apps_Gallery2 - Gitiles

 /*
  * Copyright (C) 2012 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.android.gallery3d.exif;

 import java.io.FilterOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;

 public class ExifOutputStream extends FilterOutputStream {
     private static final String TAG = "ExifOutputStream";

     private static final int STATE_SOI = 0;
     private static final int STATE_FRAME_HEADER = 1;
     private static final int STATE_JPEG_DATA = 2;

     private static final int EXIF_HEADER = 0x45786966;
     private static final short TIFF_HEADER = 0x002A;
     private static final short TIFF_BIG_ENDIAN = 0x4d4d;
     private static final short TIFF_LITTLE_ENDIAN = 0x4949;
     private static final short TAG_SIZE = 12;
     private static final short TIFF_HEADER_SIZE = 8;

     private ExifData mExifData;
     private int mState = STATE_SOI;
     private int mByteToSkip;
     private int mByteToCopy;
     private ByteBuffer mBuffer = ByteBuffer.allocate(4);

     public ExifOutputStream(OutputStream ou) {
         super(ou);
     }

     public void setExifData(ExifData exifData) {
         mExifData = exifData;
     }

     public ExifData getExifData() {
         return mExifData;
     }

     private int requestByteToBuffer(int requestByteCount, byte[] buffer
             , int offset, int length) {
         int byteNeeded = requestByteCount - mBuffer.position();
         int byteToRead = length > byteNeeded ? byteNeeded : length;
         mBuffer.put(buffer, offset, byteToRead);
         return byteToRead;
     }

     @Override
     public void write(byte[] buffer, int offset, int length) throws IOException {
         while((mByteToSkip > 0 || mByteToCopy > 0 || mState != STATE_JPEG_DATA)
                 && length > 0) {
             if (mByteToSkip > 0) {
                 int byteToProcess = length > mByteToSkip ? mByteToSkip : length;
                 length -= byteToProcess;
                 mByteToSkip -= byteToProcess;
                 offset += byteToProcess;
             }
             if (mByteToCopy > 0) {
                 int byteToProcess = length > mByteToCopy ? mByteToCopy : length;
                 out.write(buffer, offset, byteToProcess);
                 length -= byteToProcess;
                 mByteToCopy -= byteToProcess;
                 offset += byteToProcess;
             }
             if (length == 0) return;
             switch (mState) {
                 case STATE_SOI:
                     int byteRead = requestByteToBuffer(2, buffer, offset, length);
                     offset += byteRead;
                     length -= byteRead;
                     if (mBuffer.position() < 2) return;
                     mBuffer.rewind();
                     assert(mBuffer.getShort() == JpegHeader.SOI);
                     out.write(mBuffer.array(), 0 ,2);
                     mState = STATE_FRAME_HEADER;
                     mBuffer.rewind();
                     writeExifData();
                     break;
                 case STATE_FRAME_HEADER:
                     // We ignore the APP1 segment and copy all other segments until SOF tag.
                     byteRead = requestByteToBuffer(4, buffer, offset, length);
                     offset += byteRead;
                     length -= byteRead;
                     // Check if this image data doesn't contain SOF.
                     if (mBuffer.position() == 2) {
                         short tag = mBuffer.getShort();
                         if (tag == JpegHeader.EOI) {
                             out.write(mBuffer.array(), 0, 2);
                             mBuffer.rewind();
                         }
                     }
                     if (mBuffer.position() < 4) return;
                     mBuffer.rewind();
                     short marker = mBuffer.getShort();
                     if (marker == JpegHeader.APP1) {
                         mByteToSkip = (mBuffer.getShort() & 0xff) - 2;
                         mState = STATE_JPEG_DATA;
                     } else if (!JpegHeader.isSofMarker(marker)) {
                         out.write(mBuffer.array(), 0, 4);
                         mByteToCopy = (mBuffer.getShort() & 0xff) - 2;
                     } else {
                         out.write(mBuffer.array(), 0, 4);
                         mState = STATE_JPEG_DATA;
                     }
                     mBuffer.rewind();
             }
         }
         if (length > 0) {
             out.write(buffer, offset, length);
         }
     }

     @Override
     public void write(int oneByte) throws IOException {
         byte[] buf = new byte[] {(byte) (0xff & oneByte)};
         write(buf);
     }

     @Override
     public void write(byte[] buffer) throws IOException {
         write(buffer, 0, buffer.length);
     }

     private void writeExifData() throws IOException {
         createRequiredIfdAndTag();
         int exifSize = calculateAllOffset();
         OrderedDataOutputStream dataOutputStream = new OrderedDataOutputStream(out);
         dataOutputStream.setByteOrder(ByteOrder.BIG_ENDIAN);
         dataOutputStream.writeShort(JpegHeader.APP1);
         dataOutputStream.writeShort((short) (exifSize + 8));
         dataOutputStream.writeInt(EXIF_HEADER);
         dataOutputStream.writeShort((short) 0x0000);
         if (mExifData.getByteOrder() == ByteOrder.BIG_ENDIAN) {
             dataOutputStream.writeShort(TIFF_BIG_ENDIAN);
         } else {
             dataOutputStream.writeShort(TIFF_LITTLE_ENDIAN);
         }
         dataOutputStream.setByteOrder(mExifData.getByteOrder());
         dataOutputStream.writeShort(TIFF_HEADER);
         dataOutputStream.writeInt(8);
         writeAllTags(dataOutputStream);
         writeThumbnail(dataOutputStream);
     }

     private void writeThumbnail(OrderedDataOutputStream dataOutputStream) throws IOException {
         if (mExifData.hasCompressedThumbnail()) {
             dataOutputStream.write(mExifData.getCompressedThumbnail());
         } else if (mExifData.hasUncompressedStrip()) {
             for (int i = 0; i < mExifData.getStripCount(); i++) {
                 dataOutputStream.write(mExifData.getStrip(i));
             }
         }
     }

     private void writeAllTags(OrderedDataOutputStream dataOutputStream) throws IOException {
         writeIfd(mExifData.getIfdData(IfdId.TYPE_IFD_0), dataOutputStream);
         writeIfd(mExifData.getIfdData(IfdId.TYPE_IFD_EXIF), dataOutputStream);
         IfdData interoperabilityIfd = mExifData.getIfdData(IfdId.TYPE_IFD_INTEROPERABILITY);
         if (interoperabilityIfd != null) {
             writeIfd(interoperabilityIfd, dataOutputStream);
         }
         IfdData gpsIfd = mExifData.getIfdData(IfdId.TYPE_IFD_GPS);
         if (gpsIfd != null) {
             writeIfd(gpsIfd, dataOutputStream);
         }
         IfdData ifd1 = mExifData.getIfdData(IfdId.TYPE_IFD_1);
         if (ifd1 != null) {
             writeIfd(mExifData.getIfdData(IfdId.TYPE_IFD_1), dataOutputStream);
         }
     }

     private void writeIfd(IfdData ifd, OrderedDataOutputStream dataOutputStream)
             throws IOException {
         ExifTag[] tags = ifd.getAllTags();
         dataOutputStream.writeShort((short) tags.length);
         for (ExifTag tag: tags) {
             dataOutputStream.writeShort(tag.getTagId());
             dataOutputStream.writeShort(tag.getDataType());
             dataOutputStream.writeInt(tag.getComponentCount());
             if (tag.getDataSize() > 4) {
                 dataOutputStream.writeInt(tag.getOffset());
             } else {
                 writeTagValue(tag, dataOutputStream);
                 for (int i = 0, n = 4 - tag.getDataSize(); i < n; i++) {
                     dataOutputStream.write(0);
                 }
             }
         }
         dataOutputStream.writeInt(ifd.getOffsetToNextIfd());
         for (ExifTag tag: tags) {
             if (tag.getDataSize() > 4) {
                 writeTagValue(tag, dataOutputStream);
             }
         }
     }

     private void writeTagValue(ExifTag tag, OrderedDataOutputStream dataOutputStream)
             throws IOException {
         switch (tag.getDataType()) {
             case ExifTag.TYPE_ASCII:
                 dataOutputStream.write(tag.getString().getBytes());
                 int remain = tag.getComponentCount() - tag.getString().length();
                 for (int i = 0; i < remain; i++) {
                     dataOutputStream.write(0);
                 }
                 break;
             case ExifTag.TYPE_LONG:
                 for (int i = 0, n = tag.getComponentCount(); i < n; i++) {
                     dataOutputStream.writeInt(tag.getLong(i));
                 }
                 break;
             case ExifTag.TYPE_RATIONAL:
             case ExifTag.TYPE_UNSIGNED_RATIONAL:
                 for (int i = 0, n = tag.getComponentCount(); i < n; i++) {
                     dataOutputStream.writeRational(tag.getRational(i));
                 }
                 break;
             case ExifTag.TYPE_UNDEFINED:
             case ExifTag.TYPE_UNSIGNED_BYTE:
                 byte[] buf = new byte[tag.getComponentCount()];
                 tag.getBytes(buf);
                 dataOutputStream.write(buf);
                 break;
             case ExifTag.TYPE_UNSIGNED_LONG:
                 for (int i = 0, n = tag.getComponentCount(); i < n; i++) {
                     dataOutputStream.writeInt((int) tag.getUnsignedLong(i));
                 }
                 break;
             case ExifTag.TYPE_UNSIGNED_SHORT:
                 for (int i = 0, n = tag.getComponentCount(); i < n; i++) {
                     dataOutputStream.writeShort((short) tag.getUnsignedShort(i));
                 }
                 break;
         }
     }

     private int calculateOffsetOfIfd(IfdData ifd, int offset) {
         offset += 2 + ifd.getTagCount() * TAG_SIZE + 4;
         ExifTag[] tags = ifd.getAllTags();
         for(ExifTag tag: tags) {
             if (tag.getDataSize() > 4) {
                 tag.setOffset(offset);
                 offset += tag.getDataSize();
             }
         }
         return offset;
     }

     private void createRequiredIfdAndTag() {
         // IFD0 is required for all file
         IfdData ifd0 = mExifData.getIfdData(IfdId.TYPE_IFD_0);
         if (ifd0 == null) {
             ifd0 = new IfdData(IfdId.TYPE_IFD_0);
             mExifData.addIfdData(ifd0);
         }
         ExifTag exifOffsetTag = new ExifTag(ExifTag.TAG_EXIF_IFD,
                 ExifTag.TYPE_UNSIGNED_LONG, 1, IfdId.TYPE_IFD_0);
         ifd0.setTag(exifOffsetTag);

         // Exif IFD is required for all file.
         IfdData exifIfd = mExifData.getIfdData(IfdId.TYPE_IFD_EXIF);
         if (exifIfd == null) {
             exifIfd = new IfdData(IfdId.TYPE_IFD_EXIF);
             mExifData.addIfdData(exifIfd);
         }

         // GPS IFD
         IfdData gpsIfd = mExifData.getIfdData(IfdId.TYPE_IFD_GPS);
         if (gpsIfd != null) {
             ExifTag gpsOffsetTag = new ExifTag(ExifTag.TAG_GPS_IFD,
                     ExifTag.TYPE_UNSIGNED_LONG, 1, IfdId.TYPE_IFD_0);
             ifd0.setTag(gpsOffsetTag);
         }

         // Interoperability IFD
         IfdData interIfd = mExifData.getIfdData(IfdId.TYPE_IFD_INTEROPERABILITY);
         if (interIfd != null) {
             ExifTag interOffsetTag = new ExifTag(ExifTag.TAG_INTEROPERABILITY_IFD,
                     ExifTag.TYPE_UNSIGNED_LONG, 1, IfdId.TYPE_IFD_EXIF);
             exifIfd.setTag(interOffsetTag);
         }

         IfdData ifd1 = mExifData.getIfdData(IfdId.TYPE_IFD_1);

         // thumbnail
         if (mExifData.hasCompressedThumbnail()) {
             if (ifd1 == null) {
                 ifd1 = new IfdData(IfdId.TYPE_IFD_1);
                 mExifData.addIfdData(ifd1);
             }
             ExifTag offsetTag = new ExifTag(ExifTag.TAG_JPEG_INTERCHANGE_FORMAT,
                     ExifTag.TYPE_UNSIGNED_LONG, 1, IfdId.TYPE_IFD_1);
             ifd1.setTag(offsetTag);
             ExifTag lengthTag = new ExifTag(ExifTag.TAG_JPEG_INTERCHANGE_FORMAT_LENGTH,
                     ExifTag.TYPE_UNSIGNED_LONG, 1, IfdId.TYPE_IFD_1);
             lengthTag.setValue(mExifData.getCompressedThumbnail().length);
             ifd1.setTag(lengthTag);
         } else if (mExifData.hasUncompressedStrip()){
             if (ifd1 == null) {
                 ifd1 = new IfdData(IfdId.TYPE_IFD_1);
                 mExifData.addIfdData(ifd1);
             }
             int stripCount = mExifData.getStripCount();
             ExifTag offsetTag = new ExifTag(ExifTag.TAG_STRIP_OFFSETS,
                     ExifTag.TYPE_UNSIGNED_LONG, stripCount, IfdId.TYPE_IFD_1);
             ExifTag lengthTag = new ExifTag(ExifTag.TAG_STRIP_BYTE_COUNTS,
                     ExifTag.TYPE_UNSIGNED_LONG, stripCount, IfdId.TYPE_IFD_1);
             long[] lengths = new long[stripCount];
             for (int i = 0; i < mExifData.getStripCount(); i++) {
                 lengths[i] = mExifData.getStrip(i).length;
             }
             lengthTag.setValue(lengths);
             ifd1.setTag(offsetTag);
             ifd1.setTag(lengthTag);
         }
     }

     private int calculateAllOffset() {
         int offset = TIFF_HEADER_SIZE;
         IfdData ifd0 = mExifData.getIfdData(IfdId.TYPE_IFD_0);
         offset = calculateOffsetOfIfd(ifd0, offset);
         ifd0.getTag(ExifTag.TAG_EXIF_IFD).setValue(offset);

         IfdData exifIfd = mExifData.getIfdData(IfdId.TYPE_IFD_EXIF);
         offset = calculateOffsetOfIfd(exifIfd, offset);

         IfdData interIfd = mExifData.getIfdData(IfdId.TYPE_IFD_INTEROPERABILITY);
         if (interIfd != null) {
             exifIfd.getTag(ExifTag.TAG_INTEROPERABILITY_IFD).setValue(offset);
             offset = calculateOffsetOfIfd(interIfd, offset);
         }

         IfdData gpsIfd = mExifData.getIfdData(IfdId.TYPE_IFD_GPS);
         if (gpsIfd != null) {
             ifd0.getTag(ExifTag.TAG_GPS_IFD).setValue(offset);
             offset = calculateOffsetOfIfd(gpsIfd, offset);
         }

         IfdData ifd1 = mExifData.getIfdData(IfdId.TYPE_IFD_1);
         if (ifd1 != null) {
             ifd0.setOffsetToNextIfd(offset);
             offset = calculateOffsetOfIfd(ifd1, offset);
         }

         // thumbnail
         if (mExifData.hasCompressedThumbnail()) {
             ifd1.getTag(ExifTag.TAG_JPEG_INTERCHANGE_FORMAT).setValue(offset);
             offset += mExifData.getCompressedThumbnail().length;
         } else if (mExifData.hasUncompressedStrip()){
             int stripCount = mExifData.getStripCount();
             long[] offsets = new long[stripCount];
             for (int i = 0; i < mExifData.getStripCount(); i++) {
                 offsets[i] = offset;
                 offset += mExifData.getStrip(i).length;
             }
             ifd1.getTag(ExifTag.TAG_STRIP_OFFSETS).setValue(offsets);
         }
         return offset;
     }
 }
	/*
	* Copyright (C) 2012 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.android.gallery3d.exif;

	import java.io.FilterOutputStream;
	import java.io.IOException;
	import java.io.OutputStream;
	import java.nio.ByteBuffer;
	import java.nio.ByteOrder;

	public class ExifOutputStream extends FilterOutputStream {
	private static final String TAG = "ExifOutputStream";

	private static final int STATE_SOI = 0;
	private static final int STATE_FRAME_HEADER = 1;
	private static final int STATE_JPEG_DATA = 2;

	private static final int EXIF_HEADER = 0x45786966;
	private static final short TIFF_HEADER = 0x002A;
	private static final short TIFF_BIG_ENDIAN = 0x4d4d;
	private static final short TIFF_LITTLE_ENDIAN = 0x4949;
	private static final short TAG_SIZE = 12;
	private static final short TIFF_HEADER_SIZE = 8;

	private ExifData mExifData;
	private int mState = STATE_SOI;
	private int mByteToSkip;
	private int mByteToCopy;
	private ByteBuffer mBuffer = ByteBuffer.allocate(4);

	public ExifOutputStream(OutputStream ou) {
	super(ou);
	}

	public void setExifData(ExifData exifData) {
	mExifData = exifData;
	}

	public ExifData getExifData() {
	return mExifData;
	}

	private int requestByteToBuffer(int requestByteCount, byte[] buffer
	, int offset, int length) {
	int byteNeeded = requestByteCount - mBuffer.position();
	int byteToRead = length > byteNeeded ? byteNeeded : length;
	mBuffer.put(buffer, offset, byteToRead);
	return byteToRead;
	}

	@Override
	public void write(byte[] buffer, int offset, int length) throws IOException {
	while((mByteToSkip > 0 \|\| mByteToCopy > 0 \|\| mState != STATE_JPEG_DATA)
	&& length > 0) {
	if (mByteToSkip > 0) {
	int byteToProcess = length > mByteToSkip ? mByteToSkip : length;
	length -= byteToProcess;
	mByteToSkip -= byteToProcess;
	offset += byteToProcess;
	}
	if (mByteToCopy > 0) {
	int byteToProcess = length > mByteToCopy ? mByteToCopy : length;
	out.write(buffer, offset, byteToProcess);
	length -= byteToProcess;
	mByteToCopy -= byteToProcess;
	offset += byteToProcess;
	}
	if (length == 0) return;
	switch (mState) {
	case STATE_SOI:
	int byteRead = requestByteToBuffer(2, buffer, offset, length);
	offset += byteRead;
	length -= byteRead;
	if (mBuffer.position() < 2) return;
	mBuffer.rewind();
	assert(mBuffer.getShort() == JpegHeader.SOI);
	out.write(mBuffer.array(), 0 ,2);
	mState = STATE_FRAME_HEADER;
	mBuffer.rewind();
	writeExifData();
	break;
	case STATE_FRAME_HEADER:
	// We ignore the APP1 segment and copy all other segments until SOF tag.
	byteRead = requestByteToBuffer(4, buffer, offset, length);
	offset += byteRead;
	length -= byteRead;
	// Check if this image data doesn't contain SOF.
	if (mBuffer.position() == 2) {
	short tag = mBuffer.getShort();
	if (tag == JpegHeader.EOI) {
	out.write(mBuffer.array(), 0, 2);
	mBuffer.rewind();
	}
	}
	if (mBuffer.position() < 4) return;
	mBuffer.rewind();
	short marker = mBuffer.getShort();
	if (marker == JpegHeader.APP1) {
	mByteToSkip = (mBuffer.getShort() & 0xff) - 2;
	mState = STATE_JPEG_DATA;
	} else if (!JpegHeader.isSofMarker(marker)) {
	out.write(mBuffer.array(), 0, 4);
	mByteToCopy = (mBuffer.getShort() & 0xff) - 2;
	} else {
	out.write(mBuffer.array(), 0, 4);
	mState = STATE_JPEG_DATA;
	}
	mBuffer.rewind();
	}
	}
	if (length > 0) {
	out.write(buffer, offset, length);
	}
	}

	@Override
	public void write(int oneByte) throws IOException {
	byte[] buf = new byte[] {(byte) (0xff & oneByte)};
	write(buf);
	}

	@Override
	public void write(byte[] buffer) throws IOException {
	write(buffer, 0, buffer.length);
	}

	private void writeExifData() throws IOException {
	createRequiredIfdAndTag();
	int exifSize = calculateAllOffset();
	OrderedDataOutputStream dataOutputStream = new OrderedDataOutputStream(out);
	dataOutputStream.setByteOrder(ByteOrder.BIG_ENDIAN);
	dataOutputStream.writeShort(JpegHeader.APP1);
	dataOutputStream.writeShort((short) (exifSize + 8));
	dataOutputStream.writeInt(EXIF_HEADER);
	dataOutputStream.writeShort((short) 0x0000);
	if (mExifData.getByteOrder() == ByteOrder.BIG_ENDIAN) {
	dataOutputStream.writeShort(TIFF_BIG_ENDIAN);
	} else {
	dataOutputStream.writeShort(TIFF_LITTLE_ENDIAN);
	}
	dataOutputStream.setByteOrder(mExifData.getByteOrder());
	dataOutputStream.writeShort(TIFF_HEADER);
	dataOutputStream.writeInt(8);
	writeAllTags(dataOutputStream);
	writeThumbnail(dataOutputStream);
	}

	private void writeThumbnail(OrderedDataOutputStream dataOutputStream) throws IOException {
	if (mExifData.hasCompressedThumbnail()) {
	dataOutputStream.write(mExifData.getCompressedThumbnail());
	} else if (mExifData.hasUncompressedStrip()) {
	for (int i = 0; i < mExifData.getStripCount(); i++) {
	dataOutputStream.write(mExifData.getStrip(i));
	}
	}
	}

	private void writeAllTags(OrderedDataOutputStream dataOutputStream) throws IOException {
	writeIfd(mExifData.getIfdData(IfdId.TYPE_IFD_0), dataOutputStream);
	writeIfd(mExifData.getIfdData(IfdId.TYPE_IFD_EXIF), dataOutputStream);
	IfdData interoperabilityIfd = mExifData.getIfdData(IfdId.TYPE_IFD_INTEROPERABILITY);
	if (interoperabilityIfd != null) {
	writeIfd(interoperabilityIfd, dataOutputStream);
	}
	IfdData gpsIfd = mExifData.getIfdData(IfdId.TYPE_IFD_GPS);
	if (gpsIfd != null) {
	writeIfd(gpsIfd, dataOutputStream);
	}
	IfdData ifd1 = mExifData.getIfdData(IfdId.TYPE_IFD_1);
	if (ifd1 != null) {
	writeIfd(mExifData.getIfdData(IfdId.TYPE_IFD_1), dataOutputStream);
	}
	}

	private void writeIfd(IfdData ifd, OrderedDataOutputStream dataOutputStream)
	throws IOException {
	ExifTag[] tags = ifd.getAllTags();
	dataOutputStream.writeShort((short) tags.length);
	for (ExifTag tag: tags) {
	dataOutputStream.writeShort(tag.getTagId());
	dataOutputStream.writeShort(tag.getDataType());
	dataOutputStream.writeInt(tag.getComponentCount());
	if (tag.getDataSize() > 4) {
	dataOutputStream.writeInt(tag.getOffset());
	} else {
	writeTagValue(tag, dataOutputStream);
	for (int i = 0, n = 4 - tag.getDataSize(); i < n; i++) {
	dataOutputStream.write(0);
	}
	}
	}
	dataOutputStream.writeInt(ifd.getOffsetToNextIfd());
	for (ExifTag tag: tags) {
	if (tag.getDataSize() > 4) {
	writeTagValue(tag, dataOutputStream);
	}
	}
	}

	private void writeTagValue(ExifTag tag, OrderedDataOutputStream dataOutputStream)
	throws IOException {
	switch (tag.getDataType()) {
	case ExifTag.TYPE_ASCII:
	dataOutputStream.write(tag.getString().getBytes());
	int remain = tag.getComponentCount() - tag.getString().length();
	for (int i = 0; i < remain; i++) {
	dataOutputStream.write(0);
	}
	break;
	case ExifTag.TYPE_LONG:
	for (int i = 0, n = tag.getComponentCount(); i < n; i++) {
	dataOutputStream.writeInt(tag.getLong(i));
	}
	break;
	case ExifTag.TYPE_RATIONAL:
	case ExifTag.TYPE_UNSIGNED_RATIONAL:
	for (int i = 0, n = tag.getComponentCount(); i < n; i++) {
	dataOutputStream.writeRational(tag.getRational(i));
	}
	break;
	case ExifTag.TYPE_UNDEFINED:
	case ExifTag.TYPE_UNSIGNED_BYTE:
	byte[] buf = new byte[tag.getComponentCount()];
	tag.getBytes(buf);
	dataOutputStream.write(buf);
	break;
	case ExifTag.TYPE_UNSIGNED_LONG:
	for (int i = 0, n = tag.getComponentCount(); i < n; i++) {
	dataOutputStream.writeInt((int) tag.getUnsignedLong(i));
	}
	break;
	case ExifTag.TYPE_UNSIGNED_SHORT:
	for (int i = 0, n = tag.getComponentCount(); i < n; i++) {
	dataOutputStream.writeShort((short) tag.getUnsignedShort(i));
	}
	break;
	}
	}

	private int calculateOffsetOfIfd(IfdData ifd, int offset) {
	offset += 2 + ifd.getTagCount() * TAG_SIZE + 4;
	ExifTag[] tags = ifd.getAllTags();
	for(ExifTag tag: tags) {
	if (tag.getDataSize() > 4) {
	tag.setOffset(offset);
	offset += tag.getDataSize();
	}
	}
	return offset;
	}

	private void createRequiredIfdAndTag() {
	// IFD0 is required for all file
	IfdData ifd0 = mExifData.getIfdData(IfdId.TYPE_IFD_0);
	if (ifd0 == null) {
	ifd0 = new IfdData(IfdId.TYPE_IFD_0);
	mExifData.addIfdData(ifd0);
	}
	ExifTag exifOffsetTag = new ExifTag(ExifTag.TAG_EXIF_IFD,
	ExifTag.TYPE_UNSIGNED_LONG, 1, IfdId.TYPE_IFD_0);
	ifd0.setTag(exifOffsetTag);

	// Exif IFD is required for all file.
	IfdData exifIfd = mExifData.getIfdData(IfdId.TYPE_IFD_EXIF);
	if (exifIfd == null) {
	exifIfd = new IfdData(IfdId.TYPE_IFD_EXIF);
	mExifData.addIfdData(exifIfd);
	}

	// GPS IFD
	IfdData gpsIfd = mExifData.getIfdData(IfdId.TYPE_IFD_GPS);
	if (gpsIfd != null) {
	ExifTag gpsOffsetTag = new ExifTag(ExifTag.TAG_GPS_IFD,
	ExifTag.TYPE_UNSIGNED_LONG, 1, IfdId.TYPE_IFD_0);
	ifd0.setTag(gpsOffsetTag);
	}

	// Interoperability IFD
	IfdData interIfd = mExifData.getIfdData(IfdId.TYPE_IFD_INTEROPERABILITY);
	if (interIfd != null) {
	ExifTag interOffsetTag = new ExifTag(ExifTag.TAG_INTEROPERABILITY_IFD,
	ExifTag.TYPE_UNSIGNED_LONG, 1, IfdId.TYPE_IFD_EXIF);
	exifIfd.setTag(interOffsetTag);
	}

	IfdData ifd1 = mExifData.getIfdData(IfdId.TYPE_IFD_1);

	// thumbnail
	if (mExifData.hasCompressedThumbnail()) {
	if (ifd1 == null) {
	ifd1 = new IfdData(IfdId.TYPE_IFD_1);
	mExifData.addIfdData(ifd1);
	}
	ExifTag offsetTag = new ExifTag(ExifTag.TAG_JPEG_INTERCHANGE_FORMAT,
	ExifTag.TYPE_UNSIGNED_LONG, 1, IfdId.TYPE_IFD_1);
	ifd1.setTag(offsetTag);
	ExifTag lengthTag = new ExifTag(ExifTag.TAG_JPEG_INTERCHANGE_FORMAT_LENGTH,
	ExifTag.TYPE_UNSIGNED_LONG, 1, IfdId.TYPE_IFD_1);
	lengthTag.setValue(mExifData.getCompressedThumbnail().length);
	ifd1.setTag(lengthTag);
	} else if (mExifData.hasUncompressedStrip()){
	if (ifd1 == null) {
	ifd1 = new IfdData(IfdId.TYPE_IFD_1);
	mExifData.addIfdData(ifd1);
	}
	int stripCount = mExifData.getStripCount();
	ExifTag offsetTag = new ExifTag(ExifTag.TAG_STRIP_OFFSETS,
	ExifTag.TYPE_UNSIGNED_LONG, stripCount, IfdId.TYPE_IFD_1);
	ExifTag lengthTag = new ExifTag(ExifTag.TAG_STRIP_BYTE_COUNTS,
	ExifTag.TYPE_UNSIGNED_LONG, stripCount, IfdId.TYPE_IFD_1);
	long[] lengths = new long[stripCount];
	for (int i = 0; i < mExifData.getStripCount(); i++) {
	lengths[i] = mExifData.getStrip(i).length;
	}
	lengthTag.setValue(lengths);
	ifd1.setTag(offsetTag);
	ifd1.setTag(lengthTag);
	}
	}

	private int calculateAllOffset() {
	int offset = TIFF_HEADER_SIZE;
	IfdData ifd0 = mExifData.getIfdData(IfdId.TYPE_IFD_0);
	offset = calculateOffsetOfIfd(ifd0, offset);
	ifd0.getTag(ExifTag.TAG_EXIF_IFD).setValue(offset);

	IfdData exifIfd = mExifData.getIfdData(IfdId.TYPE_IFD_EXIF);
	offset = calculateOffsetOfIfd(exifIfd, offset);

	IfdData interIfd = mExifData.getIfdData(IfdId.TYPE_IFD_INTEROPERABILITY);
	if (interIfd != null) {
	exifIfd.getTag(ExifTag.TAG_INTEROPERABILITY_IFD).setValue(offset);
	offset = calculateOffsetOfIfd(interIfd, offset);
	}

	IfdData gpsIfd = mExifData.getIfdData(IfdId.TYPE_IFD_GPS);
	if (gpsIfd != null) {
	ifd0.getTag(ExifTag.TAG_GPS_IFD).setValue(offset);
	offset = calculateOffsetOfIfd(gpsIfd, offset);
	}

	IfdData ifd1 = mExifData.getIfdData(IfdId.TYPE_IFD_1);
	if (ifd1 != null) {
	ifd0.setOffsetToNextIfd(offset);
	offset = calculateOffsetOfIfd(ifd1, offset);
	}

	// thumbnail
	if (mExifData.hasCompressedThumbnail()) {
	ifd1.getTag(ExifTag.TAG_JPEG_INTERCHANGE_FORMAT).setValue(offset);
	offset += mExifData.getCompressedThumbnail().length;
	} else if (mExifData.hasUncompressedStrip()){
	int stripCount = mExifData.getStripCount();
	long[] offsets = new long[stripCount];
	for (int i = 0; i < mExifData.getStripCount(); i++) {
	offsets[i] = offset;
	offset += mExifData.getStrip(i).length;
	}
	ifd1.getTag(ExifTag.TAG_STRIP_OFFSETS).setValue(offsets);
	}
	return offset;
	}
	}