blob: 5467d423d754fa1d687e69c9389e0fe1bf784c7e [file] [log] [blame]
/*
* 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 android.util.Log;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteOrder;
import java.nio.charset.Charset;
import java.util.Map.Entry;
import java.util.TreeMap;
/**
* This class provides a low-level EXIF parsing API. Given a JPEG format
* InputStream, the caller can request which IFD's to read via
* {@link #parse(InputStream, int)} with given options.
* <p>
* Below is an example of getting EXIF data from IFD 0 and EXIF IFD using the
* parser.
*
* <pre>
* void parse() {
* ExifParser parser = ExifParser.parse(mImageInputStream,
* ExifParser.OPTION_IFD_0 | ExifParser.OPTIONS_IFD_EXIF);
* int event = parser.next();
* while (event != ExifParser.EVENT_END) {
* switch (event) {
* case ExifParser.EVENT_START_OF_IFD:
* break;
* case ExifParser.EVENT_NEW_TAG:
* ExifTag tag = parser.getTag();
* if (!tag.hasValue()) {
* parser.registerForTagValue(tag);
* } else {
* processTag(tag);
* }
* break;
* case ExifParser.EVENT_VALUE_OF_REGISTERED_TAG:
* tag = parser.getTag();
* if (tag.getDataType() != ExifTag.TYPE_UNDEFINED) {
* processTag(tag);
* }
* break;
* }
* event = parser.next();
* }
* }
*
* void processTag(ExifTag tag) {
* // process the tag as you like.
* }
* </pre>
*/
class ExifParser {
private static final boolean LOGV = false;
private static final String TAG = "ExifParser";
/**
* When the parser reaches a new IFD area. Call {@link #getCurrentIfd()} to
* know which IFD we are in.
*/
public static final int EVENT_START_OF_IFD = 0;
/**
* When the parser reaches a new tag. Call {@link #getTag()}to get the
* corresponding tag.
*/
public static final int EVENT_NEW_TAG = 1;
/**
* When the parser reaches the value area of tag that is registered by
* {@link #registerForTagValue(ExifTag)} previously. Call {@link #getTag()}
* to get the corresponding tag.
*/
public static final int EVENT_VALUE_OF_REGISTERED_TAG = 2;
/**
* When the parser reaches the compressed image area.
*/
public static final int EVENT_COMPRESSED_IMAGE = 3;
/**
* When the parser reaches the uncompressed image strip. Call
* {@link #getStripIndex()} to get the index of the strip.
*
* @see #getStripIndex()
* @see #getStripCount()
*/
public static final int EVENT_UNCOMPRESSED_STRIP = 4;
/**
* When there is nothing more to parse.
*/
public static final int EVENT_END = 5;
/**
* Option bit to request to parse IFD0.
*/
public static final int OPTION_IFD_0 = 1 << 0;
/**
* Option bit to request to parse IFD1.
*/
public static final int OPTION_IFD_1 = 1 << 1;
/**
* Option bit to request to parse Exif-IFD.
*/
public static final int OPTION_IFD_EXIF = 1 << 2;
/**
* Option bit to request to parse GPS-IFD.
*/
public static final int OPTION_IFD_GPS = 1 << 3;
/**
* Option bit to request to parse Interoperability-IFD.
*/
public static final int OPTION_IFD_INTEROPERABILITY = 1 << 4;
/**
* Option bit to request to parse thumbnail.
*/
public static final int OPTION_THUMBNAIL = 1 << 5;
protected static final int EXIF_HEADER = 0x45786966; // EXIF header "Exif"
protected static final short EXIF_HEADER_TAIL = (short) 0x0000; // EXIF header in APP1
// TIFF header
protected static final short LITTLE_ENDIAN_TAG = (short) 0x4949; // "II"
protected static final short BIG_ENDIAN_TAG = (short) 0x4d4d; // "MM"
protected static final short TIFF_HEADER_TAIL = 0x002A;
protected static final int TAG_SIZE = 12;
protected static final int OFFSET_SIZE = 2;
private static final Charset US_ASCII = Charset.forName("US-ASCII");
protected static final int DEFAULT_IFD0_OFFSET = 8;
private final CountedDataInputStream mTiffStream;
private final int mOptions;
private int mIfdStartOffset = 0;
private int mNumOfTagInIfd = 0;
private int mIfdType;
private ExifTag mTag;
private ImageEvent mImageEvent;
private int mStripCount;
private ExifTag mStripSizeTag;
private ExifTag mJpegSizeTag;
private boolean mNeedToParseOffsetsInCurrentIfd;
private boolean mContainExifData = false;
private int mApp1End;
private int mOffsetToApp1EndFromSOF = 0;
private byte[] mDataAboveIfd0;
private int mIfd0Position;
private int mTiffStartPosition;
private final ExifInterface mInterface;
private static final short TAG_EXIF_IFD = ExifInterface
.getTrueTagKey(ExifInterface.TAG_EXIF_IFD);
private static final short TAG_GPS_IFD = ExifInterface.getTrueTagKey(ExifInterface.TAG_GPS_IFD);
private static final short TAG_INTEROPERABILITY_IFD = ExifInterface
.getTrueTagKey(ExifInterface.TAG_INTEROPERABILITY_IFD);
private static final short TAG_JPEG_INTERCHANGE_FORMAT = ExifInterface
.getTrueTagKey(ExifInterface.TAG_JPEG_INTERCHANGE_FORMAT);
private static final short TAG_JPEG_INTERCHANGE_FORMAT_LENGTH = ExifInterface
.getTrueTagKey(ExifInterface.TAG_JPEG_INTERCHANGE_FORMAT_LENGTH);
private static final short TAG_STRIP_OFFSETS = ExifInterface
.getTrueTagKey(ExifInterface.TAG_STRIP_OFFSETS);
private static final short TAG_STRIP_BYTE_COUNTS = ExifInterface
.getTrueTagKey(ExifInterface.TAG_STRIP_BYTE_COUNTS);
private final TreeMap<Integer, Object> mCorrespondingEvent = new TreeMap<Integer, Object>();
private boolean isIfdRequested(int ifdType) {
switch (ifdType) {
case IfdId.TYPE_IFD_0:
return (mOptions & OPTION_IFD_0) != 0;
case IfdId.TYPE_IFD_1:
return (mOptions & OPTION_IFD_1) != 0;
case IfdId.TYPE_IFD_EXIF:
return (mOptions & OPTION_IFD_EXIF) != 0;
case IfdId.TYPE_IFD_GPS:
return (mOptions & OPTION_IFD_GPS) != 0;
case IfdId.TYPE_IFD_INTEROPERABILITY:
return (mOptions & OPTION_IFD_INTEROPERABILITY) != 0;
}
return false;
}
private boolean isThumbnailRequested() {
return (mOptions & OPTION_THUMBNAIL) != 0;
}
private ExifParser(InputStream inputStream, int options, ExifInterface iRef)
throws IOException, ExifInvalidFormatException {
if (inputStream == null) {
throw new IOException("Null argument inputStream to ExifParser");
}
if (LOGV) {
Log.v(TAG, "Reading exif...");
}
mInterface = iRef;
mContainExifData = seekTiffData(inputStream);
mTiffStream = new CountedDataInputStream(inputStream);
mOptions = options;
if (!mContainExifData) {
return;
}
parseTiffHeader();
long offset = mTiffStream.readUnsignedInt();
if (offset > Integer.MAX_VALUE) {
throw new ExifInvalidFormatException("Invalid offset " + offset);
}
mIfd0Position = (int) offset;
mIfdType = IfdId.TYPE_IFD_0;
if (isIfdRequested(IfdId.TYPE_IFD_0) || needToParseOffsetsInCurrentIfd()) {
registerIfd(IfdId.TYPE_IFD_0, offset);
if (offset != DEFAULT_IFD0_OFFSET) {
mDataAboveIfd0 = new byte[(int) offset - DEFAULT_IFD0_OFFSET];
read(mDataAboveIfd0);
}
}
}
/**
* Parses the the given InputStream with the given options
*
* @exception IOException
* @exception ExifInvalidFormatException
*/
protected static ExifParser parse(InputStream inputStream, int options, ExifInterface iRef)
throws IOException, ExifInvalidFormatException {
return new ExifParser(inputStream, options, iRef);
}
/**
* Parses the the given InputStream with default options; that is, every IFD
* and thumbnaill will be parsed.
*
* @exception IOException
* @exception ExifInvalidFormatException
* @see #parse(InputStream, int)
*/
protected static ExifParser parse(InputStream inputStream, ExifInterface iRef)
throws IOException, ExifInvalidFormatException {
return new ExifParser(inputStream, OPTION_IFD_0 | OPTION_IFD_1
| OPTION_IFD_EXIF | OPTION_IFD_GPS | OPTION_IFD_INTEROPERABILITY
| OPTION_THUMBNAIL, iRef);
}
/**
* Moves the parser forward and returns the next parsing event
*
* @exception IOException
* @exception ExifInvalidFormatException
* @see #EVENT_START_OF_IFD
* @see #EVENT_NEW_TAG
* @see #EVENT_VALUE_OF_REGISTERED_TAG
* @see #EVENT_COMPRESSED_IMAGE
* @see #EVENT_UNCOMPRESSED_STRIP
* @see #EVENT_END
*/
protected int next() throws IOException, ExifInvalidFormatException {
if (!mContainExifData) {
return EVENT_END;
}
int offset = mTiffStream.getReadByteCount();
int endOfTags = mIfdStartOffset + OFFSET_SIZE + TAG_SIZE * mNumOfTagInIfd;
if (offset < endOfTags) {
mTag = readTag();
if (mTag == null) {
return next();
}
if (mNeedToParseOffsetsInCurrentIfd) {
checkOffsetOrImageTag(mTag);
}
return EVENT_NEW_TAG;
} else if (offset == endOfTags) {
// There is a link to ifd1 at the end of ifd0
if (mIfdType == IfdId.TYPE_IFD_0) {
long ifdOffset = readUnsignedLong();
if (isIfdRequested(IfdId.TYPE_IFD_1) || isThumbnailRequested()) {
if (ifdOffset != 0) {
registerIfd(IfdId.TYPE_IFD_1, ifdOffset);
}
}
} else {
int offsetSize = 4;
// Some camera models use invalid length of the offset
if (mCorrespondingEvent.size() > 0) {
offsetSize = mCorrespondingEvent.firstEntry().getKey() -
mTiffStream.getReadByteCount();
}
if (offsetSize < 4) {
Log.w(TAG, "Invalid size of link to next IFD: " + offsetSize);
} else {
long ifdOffset = readUnsignedLong();
if (ifdOffset != 0) {
Log.w(TAG, "Invalid link to next IFD: " + ifdOffset);
}
}
}
}
while (mCorrespondingEvent.size() != 0) {
Entry<Integer, Object> entry = mCorrespondingEvent.pollFirstEntry();
Object event = entry.getValue();
try {
skipTo(entry.getKey());
} catch (IOException e) {
Log.w(TAG, "Failed to skip to data at: " + entry.getKey() +
" for " + event.getClass().getName() + ", the file may be broken.");
continue;
}
if (event instanceof IfdEvent) {
mIfdType = ((IfdEvent) event).ifd;
mNumOfTagInIfd = mTiffStream.readUnsignedShort();
mIfdStartOffset = entry.getKey();
if (mNumOfTagInIfd * TAG_SIZE + mIfdStartOffset + OFFSET_SIZE > mApp1End) {
Log.w(TAG, "Invalid size of IFD " + mIfdType);
return EVENT_END;
}
mNeedToParseOffsetsInCurrentIfd = needToParseOffsetsInCurrentIfd();
if (((IfdEvent) event).isRequested) {
return EVENT_START_OF_IFD;
} else {
skipRemainingTagsInCurrentIfd();
}
} else if (event instanceof ImageEvent) {
mImageEvent = (ImageEvent) event;
return mImageEvent.type;
} else {
ExifTagEvent tagEvent = (ExifTagEvent) event;
mTag = tagEvent.tag;
if (mTag.getDataType() != ExifTag.TYPE_UNDEFINED) {
readFullTagValue(mTag);
checkOffsetOrImageTag(mTag);
}
if (tagEvent.isRequested) {
return EVENT_VALUE_OF_REGISTERED_TAG;
}
}
}
return EVENT_END;
}
/**
* Skips the tags area of current IFD, if the parser is not in the tag area,
* nothing will happen.
*
* @throws IOException
* @throws ExifInvalidFormatException
*/
protected void skipRemainingTagsInCurrentIfd() throws IOException, ExifInvalidFormatException {
int endOfTags = mIfdStartOffset + OFFSET_SIZE + TAG_SIZE * mNumOfTagInIfd;
int offset = mTiffStream.getReadByteCount();
if (offset > endOfTags) {
return;
}
if (mNeedToParseOffsetsInCurrentIfd) {
while (offset < endOfTags) {
mTag = readTag();
offset += TAG_SIZE;
if (mTag == null) {
continue;
}
checkOffsetOrImageTag(mTag);
}
} else {
skipTo(endOfTags);
}
long ifdOffset = readUnsignedLong();
// For ifd0, there is a link to ifd1 in the end of all tags
if (mIfdType == IfdId.TYPE_IFD_0
&& (isIfdRequested(IfdId.TYPE_IFD_1) || isThumbnailRequested())) {
if (ifdOffset > 0) {
registerIfd(IfdId.TYPE_IFD_1, ifdOffset);
}
}
}
private boolean needToParseOffsetsInCurrentIfd() {
switch (mIfdType) {
case IfdId.TYPE_IFD_0:
return isIfdRequested(IfdId.TYPE_IFD_EXIF) || isIfdRequested(IfdId.TYPE_IFD_GPS)
|| isIfdRequested(IfdId.TYPE_IFD_INTEROPERABILITY)
|| isIfdRequested(IfdId.TYPE_IFD_1);
case IfdId.TYPE_IFD_1:
return isThumbnailRequested();
case IfdId.TYPE_IFD_EXIF:
// The offset to interoperability IFD is located in Exif IFD
return isIfdRequested(IfdId.TYPE_IFD_INTEROPERABILITY);
default:
return false;
}
}
/**
* If {@link #next()} return {@link #EVENT_NEW_TAG} or
* {@link #EVENT_VALUE_OF_REGISTERED_TAG}, call this function to get the
* corresponding tag.
* <p>
* For {@link #EVENT_NEW_TAG}, the tag may not contain the value if the size
* of the value is greater than 4 bytes. One should call
* {@link ExifTag#hasValue()} to check if the tag contains value. If there
* is no value,call {@link #registerForTagValue(ExifTag)} to have the parser
* emit {@link #EVENT_VALUE_OF_REGISTERED_TAG} when it reaches the area
* pointed by the offset.
* <p>
* When {@link #EVENT_VALUE_OF_REGISTERED_TAG} is emitted, the value of the
* tag will have already been read except for tags of undefined type. For
* tags of undefined type, call one of the read methods to get the value.
*
* @see #registerForTagValue(ExifTag)
* @see #read(byte[])
* @see #read(byte[], int, int)
* @see #readLong()
* @see #readRational()
* @see #readString(int)
* @see #readString(int, Charset)
*/
protected ExifTag getTag() {
return mTag;
}
/**
* Gets number of tags in the current IFD area.
*/
protected int getTagCountInCurrentIfd() {
return mNumOfTagInIfd;
}
/**
* Gets the ID of current IFD.
*
* @see IfdId#TYPE_IFD_0
* @see IfdId#TYPE_IFD_1
* @see IfdId#TYPE_IFD_GPS
* @see IfdId#TYPE_IFD_INTEROPERABILITY
* @see IfdId#TYPE_IFD_EXIF
*/
protected int getCurrentIfd() {
return mIfdType;
}
/**
* When receiving {@link #EVENT_UNCOMPRESSED_STRIP}, call this function to
* get the index of this strip.
*
* @see #getStripCount()
*/
protected int getStripIndex() {
return mImageEvent.stripIndex;
}
/**
* When receiving {@link #EVENT_UNCOMPRESSED_STRIP}, call this function to
* get the number of strip data.
*
* @see #getStripIndex()
*/
protected int getStripCount() {
return mStripCount;
}
/**
* When receiving {@link #EVENT_UNCOMPRESSED_STRIP}, call this function to
* get the strip size.
*/
protected int getStripSize() {
if (mStripSizeTag == null)
return 0;
return (int) mStripSizeTag.getValueAt(0);
}
/**
* When receiving {@link #EVENT_COMPRESSED_IMAGE}, call this function to get
* the image data size.
*/
protected int getCompressedImageSize() {
if (mJpegSizeTag == null) {
return 0;
}
return (int) mJpegSizeTag.getValueAt(0);
}
private void skipTo(int offset) throws IOException {
mTiffStream.skipTo(offset);
while (!mCorrespondingEvent.isEmpty() && mCorrespondingEvent.firstKey() < offset) {
mCorrespondingEvent.pollFirstEntry();
}
}
/**
* When getting {@link #EVENT_NEW_TAG} in the tag area of IFD, the tag may
* not contain the value if the size of the value is greater than 4 bytes.
* When the value is not available here, call this method so that the parser
* will emit {@link #EVENT_VALUE_OF_REGISTERED_TAG} when it reaches the area
* where the value is located.
*
* @see #EVENT_VALUE_OF_REGISTERED_TAG
*/
protected void registerForTagValue(ExifTag tag) {
if (tag.getOffset() >= mTiffStream.getReadByteCount()) {
mCorrespondingEvent.put(tag.getOffset(), new ExifTagEvent(tag, true));
}
}
private void registerIfd(int ifdType, long offset) {
// Cast unsigned int to int since the offset is always smaller
// than the size of APP1 (65536)
mCorrespondingEvent.put((int) offset, new IfdEvent(ifdType, isIfdRequested(ifdType)));
}
private void registerCompressedImage(long offset) {
mCorrespondingEvent.put((int) offset, new ImageEvent(EVENT_COMPRESSED_IMAGE));
}
private void registerUncompressedStrip(int stripIndex, long offset) {
mCorrespondingEvent.put((int) offset, new ImageEvent(EVENT_UNCOMPRESSED_STRIP
, stripIndex));
}
private ExifTag readTag() throws IOException, ExifInvalidFormatException {
short tagId = mTiffStream.readShort();
short dataFormat = mTiffStream.readShort();
long numOfComp = mTiffStream.readUnsignedInt();
if (numOfComp > Integer.MAX_VALUE) {
throw new ExifInvalidFormatException(
"Number of component is larger then Integer.MAX_VALUE");
}
// Some invalid image file contains invalid data type. Ignore those tags
if (!ExifTag.isValidType(dataFormat)) {
Log.w(TAG, String.format("Tag %04x: Invalid data type %d", tagId, dataFormat));
mTiffStream.skip(4);
return null;
}
// TODO: handle numOfComp overflow
ExifTag tag = new ExifTag(tagId, dataFormat, (int) numOfComp, mIfdType,
((int) numOfComp) != ExifTag.SIZE_UNDEFINED);
int dataSize = tag.getDataSize();
if (dataSize > 4) {
long offset = mTiffStream.readUnsignedInt();
if (offset > Integer.MAX_VALUE) {
throw new ExifInvalidFormatException(
"offset is larger then Integer.MAX_VALUE");
}
// Some invalid images put some undefined data before IFD0.
// Read the data here.
if ((offset < mIfd0Position) && (dataFormat == ExifTag.TYPE_UNDEFINED)) {
byte[] buf = new byte[(int) numOfComp];
System.arraycopy(mDataAboveIfd0, (int) offset - DEFAULT_IFD0_OFFSET,
buf, 0, (int) numOfComp);
tag.setValue(buf);
} else {
tag.setOffset((int) offset);
}
} else {
boolean defCount = tag.hasDefinedCount();
// Set defined count to 0 so we can add \0 to non-terminated strings
tag.setHasDefinedCount(false);
// Read value
readFullTagValue(tag);
tag.setHasDefinedCount(defCount);
mTiffStream.skip(4 - dataSize);
// Set the offset to the position of value.
tag.setOffset(mTiffStream.getReadByteCount() - 4);
}
return tag;
}
/**
* Check the tag, if the tag is one of the offset tag that points to the IFD
* or image the caller is interested in, register the IFD or image.
*/
private void checkOffsetOrImageTag(ExifTag tag) {
// Some invalid formattd image contains tag with 0 size.
if (tag.getComponentCount() == 0) {
return;
}
short tid = tag.getTagId();
int ifd = tag.getIfd();
if (tid == TAG_EXIF_IFD && checkAllowed(ifd, ExifInterface.TAG_EXIF_IFD)) {
if (isIfdRequested(IfdId.TYPE_IFD_EXIF)
|| isIfdRequested(IfdId.TYPE_IFD_INTEROPERABILITY)) {
registerIfd(IfdId.TYPE_IFD_EXIF, tag.getValueAt(0));
}
} else if (tid == TAG_GPS_IFD && checkAllowed(ifd, ExifInterface.TAG_GPS_IFD)) {
if (isIfdRequested(IfdId.TYPE_IFD_GPS)) {
registerIfd(IfdId.TYPE_IFD_GPS, tag.getValueAt(0));
}
} else if (tid == TAG_INTEROPERABILITY_IFD
&& checkAllowed(ifd, ExifInterface.TAG_INTEROPERABILITY_IFD)) {
if (isIfdRequested(IfdId.TYPE_IFD_INTEROPERABILITY)) {
registerIfd(IfdId.TYPE_IFD_INTEROPERABILITY, tag.getValueAt(0));
}
} else if (tid == TAG_JPEG_INTERCHANGE_FORMAT
&& checkAllowed(ifd, ExifInterface.TAG_JPEG_INTERCHANGE_FORMAT)) {
if (isThumbnailRequested()) {
registerCompressedImage(tag.getValueAt(0));
}
} else if (tid == TAG_JPEG_INTERCHANGE_FORMAT_LENGTH
&& checkAllowed(ifd, ExifInterface.TAG_JPEG_INTERCHANGE_FORMAT_LENGTH)) {
if (isThumbnailRequested()) {
mJpegSizeTag = tag;
}
} else if (tid == TAG_STRIP_OFFSETS && checkAllowed(ifd, ExifInterface.TAG_STRIP_OFFSETS)) {
if (isThumbnailRequested()) {
if (tag.hasValue()) {
for (int i = 0; i < tag.getComponentCount(); i++) {
if (tag.getDataType() == ExifTag.TYPE_UNSIGNED_SHORT) {
registerUncompressedStrip(i, tag.getValueAt(i));
} else {
registerUncompressedStrip(i, tag.getValueAt(i));
}
}
} else {
mCorrespondingEvent.put(tag.getOffset(), new ExifTagEvent(tag, false));
}
}
} else if (tid == TAG_STRIP_BYTE_COUNTS
&& checkAllowed(ifd, ExifInterface.TAG_STRIP_BYTE_COUNTS)
&&isThumbnailRequested() && tag.hasValue()) {
mStripSizeTag = tag;
}
}
private boolean checkAllowed(int ifd, int tagId) {
int info = mInterface.getTagInfo().get(tagId);
if (info == ExifInterface.DEFINITION_NULL) {
return false;
}
return ExifInterface.isIfdAllowed(info, ifd);
}
protected void readFullTagValue(ExifTag tag) throws IOException {
// Some invalid images contains tags with wrong size, check it here
short type = tag.getDataType();
if (type == ExifTag.TYPE_ASCII || type == ExifTag.TYPE_UNDEFINED ||
type == ExifTag.TYPE_UNSIGNED_BYTE) {
int size = tag.getComponentCount();
if (mCorrespondingEvent.size() > 0) {
if (mCorrespondingEvent.firstEntry().getKey() < mTiffStream.getReadByteCount()
+ size) {
Object event = mCorrespondingEvent.firstEntry().getValue();
if (event instanceof ImageEvent) {
// Tag value overlaps thumbnail, ignore thumbnail.
Log.w(TAG, "Thumbnail overlaps value for tag: \n" + tag.toString());
Entry<Integer, Object> entry = mCorrespondingEvent.pollFirstEntry();
Log.w(TAG, "Invalid thumbnail offset: " + entry.getKey());
} else {
// Tag value overlaps another tag, shorten count
if (event instanceof IfdEvent) {
Log.w(TAG, "Ifd " + ((IfdEvent) event).ifd
+ " overlaps value for tag: \n" + tag.toString());
} else if (event instanceof ExifTagEvent) {
Log.w(TAG, "Tag value for tag: \n"
+ ((ExifTagEvent) event).tag.toString()
+ " overlaps value for tag: \n" + tag.toString());
}
size = mCorrespondingEvent.firstEntry().getKey()
- mTiffStream.getReadByteCount();
Log.w(TAG, "Invalid size of tag: \n" + tag.toString()
+ " setting count to: " + size);
tag.forceSetComponentCount(size);
}
}
}
}
switch (tag.getDataType()) {
case ExifTag.TYPE_UNSIGNED_BYTE:
case ExifTag.TYPE_UNDEFINED: {
byte buf[] = new byte[tag.getComponentCount()];
read(buf);
tag.setValue(buf);
}
break;
case ExifTag.TYPE_ASCII:
tag.setValue(readString(tag.getComponentCount()));
break;
case ExifTag.TYPE_UNSIGNED_LONG: {
long value[] = new long[tag.getComponentCount()];
for (int i = 0, n = value.length; i < n; i++) {
value[i] = readUnsignedLong();
}
tag.setValue(value);
}
break;
case ExifTag.TYPE_UNSIGNED_RATIONAL: {
Rational value[] = new Rational[tag.getComponentCount()];
for (int i = 0, n = value.length; i < n; i++) {
value[i] = readUnsignedRational();
}
tag.setValue(value);
}
break;
case ExifTag.TYPE_UNSIGNED_SHORT: {
int value[] = new int[tag.getComponentCount()];
for (int i = 0, n = value.length; i < n; i++) {
value[i] = readUnsignedShort();
}
tag.setValue(value);
}
break;
case ExifTag.TYPE_LONG: {
int value[] = new int[tag.getComponentCount()];
for (int i = 0, n = value.length; i < n; i++) {
value[i] = readLong();
}
tag.setValue(value);
}
break;
case ExifTag.TYPE_RATIONAL: {
Rational value[] = new Rational[tag.getComponentCount()];
for (int i = 0, n = value.length; i < n; i++) {
value[i] = readRational();
}
tag.setValue(value);
}
break;
}
if (LOGV) {
Log.v(TAG, "\n" + tag.toString());
}
}
private void parseTiffHeader() throws IOException,
ExifInvalidFormatException {
short byteOrder = mTiffStream.readShort();
if (LITTLE_ENDIAN_TAG == byteOrder) {
mTiffStream.setByteOrder(ByteOrder.LITTLE_ENDIAN);
} else if (BIG_ENDIAN_TAG == byteOrder) {
mTiffStream.setByteOrder(ByteOrder.BIG_ENDIAN);
} else {
throw new ExifInvalidFormatException("Invalid TIFF header");
}
if (mTiffStream.readShort() != TIFF_HEADER_TAIL) {
throw new ExifInvalidFormatException("Invalid TIFF header");
}
}
private boolean seekTiffData(InputStream inputStream) throws IOException,
ExifInvalidFormatException {
CountedDataInputStream dataStream = new CountedDataInputStream(inputStream);
if (dataStream.readShort() != JpegHeader.SOI) {
throw new ExifInvalidFormatException("Invalid JPEG format");
}
short marker = dataStream.readShort();
while (marker != JpegHeader.EOI
&& !JpegHeader.isSofMarker(marker)) {
int length = dataStream.readUnsignedShort();
// Some invalid formatted image contains multiple APP1,
// try to find the one with Exif data.
if (marker == JpegHeader.APP1) {
int header = 0;
short headerTail = 0;
if (length >= 8) {
header = dataStream.readInt();
headerTail = dataStream.readShort();
length -= 6;
if (header == EXIF_HEADER && headerTail == EXIF_HEADER_TAIL) {
mTiffStartPosition = dataStream.getReadByteCount();
mApp1End = length;
mOffsetToApp1EndFromSOF = mTiffStartPosition + mApp1End;
return true;
}
}
}
if (length < 2 || (length - 2) != dataStream.skip(length - 2)) {
Log.w(TAG, "Invalid JPEG format.");
return false;
}
marker = dataStream.readShort();
}
return false;
}
protected int getOffsetToExifEndFromSOF() {
return mOffsetToApp1EndFromSOF;
}
protected int getTiffStartPosition() {
return mTiffStartPosition;
}
/**
* Reads bytes from the InputStream.
*/
protected int read(byte[] buffer, int offset, int length) throws IOException {
return mTiffStream.read(buffer, offset, length);
}
/**
* Equivalent to read(buffer, 0, buffer.length).
*/
protected int read(byte[] buffer) throws IOException {
return mTiffStream.read(buffer);
}
/**
* Reads a String from the InputStream with US-ASCII charset. The parser
* will read n bytes and convert it to ascii string. This is used for
* reading values of type {@link ExifTag#TYPE_ASCII}.
*/
protected String readString(int n) throws IOException {
return readString(n, US_ASCII);
}
/**
* Reads a String from the InputStream with the given charset. The parser
* will read n bytes and convert it to string. This is used for reading
* values of type {@link ExifTag#TYPE_ASCII}.
*/
protected String readString(int n, Charset charset) throws IOException {
if (n > 0) {
return mTiffStream.readString(n, charset);
} else {
return "";
}
}
/**
* Reads value of type {@link ExifTag#TYPE_UNSIGNED_SHORT} from the
* InputStream.
*/
protected int readUnsignedShort() throws IOException {
return mTiffStream.readShort() & 0xffff;
}
/**
* Reads value of type {@link ExifTag#TYPE_UNSIGNED_LONG} from the
* InputStream.
*/
protected long readUnsignedLong() throws IOException {
return readLong() & 0xffffffffL;
}
/**
* Reads value of type {@link ExifTag#TYPE_UNSIGNED_RATIONAL} from the
* InputStream.
*/
protected Rational readUnsignedRational() throws IOException {
long nomi = readUnsignedLong();
long denomi = readUnsignedLong();
return new Rational(nomi, denomi);
}
/**
* Reads value of type {@link ExifTag#TYPE_LONG} from the InputStream.
*/
protected int readLong() throws IOException {
return mTiffStream.readInt();
}
/**
* Reads value of type {@link ExifTag#TYPE_RATIONAL} from the InputStream.
*/
protected Rational readRational() throws IOException {
int nomi = readLong();
int denomi = readLong();
return new Rational(nomi, denomi);
}
private static class ImageEvent {
int stripIndex;
int type;
ImageEvent(int type) {
this.stripIndex = 0;
this.type = type;
}
ImageEvent(int type, int stripIndex) {
this.type = type;
this.stripIndex = stripIndex;
}
}
private static class IfdEvent {
int ifd;
boolean isRequested;
IfdEvent(int ifd, boolean isInterestedIfd) {
this.ifd = ifd;
this.isRequested = isInterestedIfd;
}
}
private static class ExifTagEvent {
ExifTag tag;
boolean isRequested;
ExifTagEvent(ExifTag tag, boolean isRequireByUser) {
this.tag = tag;
this.isRequested = isRequireByUser;
}
}
/**
* Gets the byte order of the current InputStream.
*/
protected ByteOrder getByteOrder() {
return mTiffStream.getByteOrder();
}
}