import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
private Integer getHeight(final Metadata metadata) {
    Integer value = null;
    ExifSubIFDDirectory directory = metadata.getDirectory(ExifSubIFDDirectory.class);
    if (directory != null && directory.containsTag(ExifSubIFDDirectory.TAG_EXIF_IMAGE_HEIGHT)) {
        value = directory.getInteger(ExifSubIFDDirectory.TAG_EXIF_IMAGE_HEIGHT);
    } else {
        JpegDirectory dir = metadata.getDirectory(JpegDirectory.class);
        if (dir != null && dir.containsTag(JpegDirectory.TAG_JPEG_IMAGE_HEIGHT)) {
            value = dir.getInteger(JpegDirectory.TAG_JPEG_IMAGE_HEIGHT);
        }
    }
    return value;
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void testExtract_Height() throws Exception
{
    assertEquals(600, _directory.getInt(JpegDirectory.TAG_JPEG_IMAGE_HEIGHT));
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void testGetComponent() throws Exception
{
    JpegComponent component1 = new JpegComponent(1, 2, 3);
    JpegComponent component2 = new JpegComponent(1, 2, 3);
    JpegComponent component3 = new JpegComponent(1, 2, 3);
    JpegComponent component4 = new JpegComponent(1, 2, 3);

    _directory.setObject(JpegDirectory.TAG_JPEG_COMPONENT_DATA_1, component1);
    _directory.setObject(JpegDirectory.TAG_JPEG_COMPONENT_DATA_2, component2);
    _directory.setObject(JpegDirectory.TAG_JPEG_COMPONENT_DATA_3, component3);
    _directory.setObject(JpegDirectory.TAG_JPEG_COMPONENT_DATA_4, component4);

    // component numbers are zero-indexed for this method
    assertSame(component1, _directory.getComponent(0));
    assertSame(component2, _directory.getComponent(1));
    assertSame(component3, _directory.getComponent(2));
    assertSame(component4, _directory.getComponent(3));
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
/**
 * Calculates the J:a:b chroma subsampling notation from a {@link Metadata}
 * instance generated from a JPEG image. If the non-luminance components
 * have different subsampling values or the calculation is impossible,
 * {@link Double#NaN} will be returned for all factors.
 *
 * @param metadata the {@link Metadata} instance from which to calculate.
 * @return A {@link JPEGSubsamplingNotation} with the result.
 */
public static JPEGSubsamplingNotation calculateJPEGSubsampling(Metadata metadata) {
	if (metadata == null) {
		throw new NullPointerException("metadata cannot be null");
	}

	JpegDirectory directory = metadata.getFirstDirectoryOfType(JpegDirectory.class);
	if (directory == null) {
		return new JPEGSubsamplingNotation(Double.NaN, Double.NaN, Double.NaN);
	}

	return calculateJPEGSubsampling(directory);
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void handle(Directory directory, Metadata metadata) throws MetadataException {
    // The test TIFF has width and height stored as follows according to exiv2
    //Exif.Image.ImageWidth                        Short       1  100
    //Exif.Image.ImageLength                       Short       1  75
    // and the values are found in "Thumbnail Image Width" (and Height) from Metadata Extractor
    set(directory, metadata, ExifThumbnailDirectory.TAG_THUMBNAIL_IMAGE_WIDTH, Metadata.IMAGE_WIDTH);
    set(directory, metadata, JpegDirectory.TAG_JPEG_IMAGE_WIDTH, Metadata.IMAGE_WIDTH);
    set(directory, metadata, ExifThumbnailDirectory.TAG_THUMBNAIL_IMAGE_HEIGHT, Metadata.IMAGE_LENGTH);
    set(directory, metadata, JpegDirectory.TAG_JPEG_IMAGE_HEIGHT, Metadata.IMAGE_LENGTH);
    // Bits per sample, two methods of extracting, exif overrides jpeg
    set(directory, metadata, JpegDirectory.TAG_JPEG_DATA_PRECISION, Metadata.BITS_PER_SAMPLE);
    set(directory, metadata, ExifSubIFDDirectory.TAG_BITS_PER_SAMPLE, Metadata.BITS_PER_SAMPLE);
    // Straightforward
    set(directory, metadata, ExifSubIFDDirectory.TAG_SAMPLES_PER_PIXEL, Metadata.SAMPLES_PER_PIXEL);
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
private Integer getPrecision(final Metadata metadata) {
    Integer value = null;
    JpegDirectory directory = metadata.getDirectory(JpegDirectory.class);
    if (directory != null && directory.containsTag(JpegDirectory.TAG_JPEG_DATA_PRECISION)) {
        value = directory.getInteger(JpegDirectory.TAG_JPEG_DATA_PRECISION);
    }
    return value;
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
private Integer getChannelCount(final Metadata metadata) {
    Integer value = null;
    JpegDirectory directory = metadata.getDirectory(JpegDirectory.class);
    if (directory != null && directory.containsTag(JpegDirectory.TAG_JPEG_NUMBER_OF_COMPONENTS)) {
        value = directory.getInteger(JpegDirectory.TAG_JPEG_NUMBER_OF_COMPONENTS);
    }
    return value;
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void setUp() throws JpegProcessingException, FileNotFoundException
{
    // use a known testing image
    File jpegFile = new File("Source/com/drew/metadata/jpeg/test/simple.jpg");
    JpegReader reader = new JpegReader(jpegFile);
    Metadata metadata = reader.extract();
    assertTrue(metadata.containsDirectory(JpegDirectory.class));
    _directory = (JpegDirectory)metadata.getDirectory(JpegDirectory.class);
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void testComponentData1() throws Exception
{
    JpegComponent component = (JpegComponent)_directory.getObject(JpegDirectory.TAG_JPEG_COMPONENT_DATA_1);
    assertEquals("Y", component.getComponentName());
    assertEquals(1, component.getComponentId());
    assertEquals(0, component.getQuantizationTableNumber());
    assertEquals(2, component.getHorizontalSamplingFactor());
    assertEquals(2, component.getVerticalSamplingFactor());
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void testComponentData2() throws Exception
{
    JpegComponent component = (JpegComponent)_directory.getObject(JpegDirectory.TAG_JPEG_COMPONENT_DATA_2);
    assertEquals("Cb", component.getComponentName());
    assertEquals(2, component.getComponentId());
    assertEquals(1, component.getQuantizationTableNumber());
    assertEquals(1, component.getHorizontalSamplingFactor());
    assertEquals(1, component.getVerticalSamplingFactor());
    assertEquals("Cb component: Quantization table 1, Sampling factors 1 horiz/1 vert", _directory.getDescription(JpegDirectory.TAG_JPEG_COMPONENT_DATA_2));
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void testComponentData3() throws Exception
{
    JpegComponent component = (JpegComponent)_directory.getObject(JpegDirectory.TAG_JPEG_COMPONENT_DATA_3);
    assertEquals("Cr", component.getComponentName());
    assertEquals(3, component.getComponentId());
    assertEquals(1, component.getQuantizationTableNumber());
    assertEquals(1, component.getHorizontalSamplingFactor());
    assertEquals(1, component.getVerticalSamplingFactor());
    assertEquals("Cr component: Quantization table 1, Sampling factors 1 horiz/1 vert", _directory.getDescription(JpegDirectory.TAG_JPEG_COMPONENT_DATA_3));
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void testGetComponentDescription() throws MetadataException
{
    JpegComponent component1 = new JpegComponent(1, 0x22, 0);
    _directory.setObject(JpegDirectory.TAG_JPEG_COMPONENT_DATA_1, component1);
    assertEquals("Y component: Quantization table 0, Sampling factors 2 horiz/2 vert", _directory.getDescription(JpegDirectory.TAG_JPEG_COMPONENT_DATA_1));
    assertEquals("Y component: Quantization table 0, Sampling factors 2 horiz/2 vert", _descriptor.getComponentDataDescription(0));
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public static ImageInformation readImageInformation(File imageFile)  throws IOException, MetadataException, ImageProcessingException {
    Metadata metadata = ImageMetadataReader.readMetadata(imageFile);
    ExifDirectoryBase exifDirectoryBase = metadata.getFirstDirectoryOfType(ExifDirectoryBase.class);
    JpegDirectory jpegDirectory = metadata.getFirstDirectoryOfType(JpegDirectory.class);
    IptcDirectory ipTCdirectory = metadata.getFirstDirectoryOfType(IptcDirectory.class);

    int orientation = 1;
    Date dateTaken = null;
    String uniqueID = "";

    if( exifDirectoryBase != null )
    {
        if( exifDirectoryBase.containsTag(ExifIFD0Directory.TAG_ORIENTATION))
            orientation = exifDirectoryBase.getInt(ExifIFD0Directory.TAG_ORIENTATION);

    }

    ExifSubIFDDirectory exifSubIFDDirectory = metadata.getFirstDirectoryOfType(ExifSubIFDDirectory.class);

    if( exifSubIFDDirectory != null )
    {
        if( exifSubIFDDirectory.containsTag( ExifDirectoryBase.TAG_IMAGE_UNIQUE_ID ))
            uniqueID = exifSubIFDDirectory.getString(ExifDirectoryBase.TAG_IMAGE_UNIQUE_ID);

        if( exifSubIFDDirectory.containsTag( ExifDirectoryBase.TAG_DATETIME ))
            dateTaken = exifSubIFDDirectory.getDate( ExifDirectoryBase.TAG_DATETIME );

        if( dateTaken == null && exifSubIFDDirectory.containsTag( ExifIFD0Directory.TAG_DATETIME_ORIGINAL ))
           dateTaken = exifSubIFDDirectory.getDate(ExifDirectoryBase.TAG_DATETIME_ORIGINAL);

        if( dateTaken == null && exifSubIFDDirectory.containsTag( ExifIFD0Directory.TAG_DATETIME_DIGITIZED ))
            dateTaken = exifSubIFDDirectory.getDate(ExifDirectoryBase.TAG_DATETIME_DIGITIZED);

        if( dateTaken == null )
            dateTaken = getCreationTime( imageFile );
    }

    boolean hasDeleteTag = false;

    if( ipTCdirectory != null && ipTCdirectory.getKeywords() != null )
    {
        if( containsCaseInsensitive( ipTCdirectory.getKeywords(), "delete") )
            hasDeleteTag = true;
    }

    int width = jpegDirectory.getImageWidth();
    int height = jpegDirectory.getImageHeight();

    return new ImageInformation(orientation, width, height, hasDeleteTag, uniqueID, dateTaken );
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public boolean supports(Class<? extends Directory> directoryType) {
    return directoryType == JpegDirectory.class || 
                directoryType == ExifSubIFDDirectory.class ||
                directoryType == ExifThumbnailDirectory.class ||
                directoryType == ExifIFD0Directory.class;
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
@NotNull
public static Metadata extractMetadataFromJpegSegmentReader(@NotNull JpegSegmentData segmentReader)
{
    final Metadata metadata = new Metadata();

    // Loop through looking for all SOFn segments.  When we find one, we know what type of compression
    // was used for the JPEG, and we can process the JPEG metadata in the segment too.
    for (byte i = 0; i < 16; i++) {
        // There are no SOF4 or SOF12 segments, so don't bother
        if (i == 4 || i == 12)
            continue;
        // Should never have more than one SOFn for a given 'n'.
        byte[] jpegSegment = segmentReader.getSegment((byte)(JpegSegmentReader.SEGMENT_SOF0 + i));
        if (jpegSegment == null)
            continue;
        JpegDirectory directory = metadata.getOrCreateDirectory(JpegDirectory.class);
        directory.setInt(JpegDirectory.TAG_JPEG_COMPRESSION_TYPE, i);
        new JpegReader().extract(new ByteArrayReader(jpegSegment), metadata);
        break;
    }

    // There should never be more than one COM segment.
    byte[] comSegment = segmentReader.getSegment(JpegSegmentReader.SEGMENT_COM);
    if (comSegment != null)
        new JpegCommentReader().extract(new ByteArrayReader(comSegment), metadata);

    // Loop through all APP0 segments, looking for a JFIF segment.
    for (byte[] app0Segment : segmentReader.getSegments(JpegSegmentReader.SEGMENT_APP0)) {
        if (app0Segment.length > 3 && new String(app0Segment, 0, 4).equals("JFIF"))
            new JfifReader().extract(new ByteArrayReader(app0Segment), metadata);
    }

    // Loop through all APP1 segments, checking the leading bytes to identify the format of each.
    for (byte[] app1Segment : segmentReader.getSegments(JpegSegmentReader.SEGMENT_APP1)) {
        if (app1Segment.length > 3 && "EXIF".equalsIgnoreCase(new String(app1Segment, 0, 4)))
            new ExifReader().extract(new ByteArrayReader(app1Segment), metadata);

        if (app1Segment.length > 27 && "http://ns.adobe.com/xap/1.0/".equalsIgnoreCase(new String(app1Segment, 0, 28)))
            new XmpReader().extract(new ByteArrayReader(app1Segment), metadata);
    }

    // Loop through all APP2 segments, looking for something we can process.
    for (byte[] app2Segment : segmentReader.getSegments(JpegSegmentReader.SEGMENT_APP2)) {
        if (app2Segment.length > 10 && new String(app2Segment, 0, 11).equalsIgnoreCase("ICC_PROFILE")) {
            byte[] icc = new byte[app2Segment.length-14];
            System.arraycopy(app2Segment, 14, icc, 0, app2Segment.length-14);
            new IccReader().extract(new ByteArrayReader(icc), metadata);
        }
    }

    // Loop through all APPD segments, checking the leading bytes to identify the format of each.
    for (byte[] appdSegment : segmentReader.getSegments(JpegSegmentReader.SEGMENT_APPD)) {
        if (appdSegment.length > 12 && "Photoshop 3.0".compareTo(new String(appdSegment, 0, 13))==0) {
            new PhotoshopReader().extract(new ByteArrayReader(appdSegment), metadata);
        } else {
            // TODO might be able to check for a leading 0x1c02 for IPTC data...
            new IptcReader().extract(new ByteArrayReader(appdSegment), metadata);
        }
    }

    // Loop through all APPE segments, checking the leading bytes to identify the format of each.
    for (byte[] appeSegment : segmentReader.getSegments(JpegSegmentReader.SEGMENT_APPE)) {
        if (appeSegment.length == 12 && "Adobe".compareTo(new String(appeSegment, 0, 5))==0) {
            new AdobeJpegReader().extract(new ByteArrayReader(appeSegment), metadata);
        }
    }

    return metadata;
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void testExtract_Width() throws Exception
{
    assertEquals(800, _directory.getInt(JpegDirectory.TAG_JPEG_IMAGE_WIDTH));
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void testExtract_DataPrecision() throws Exception
{
    assertEquals(8, _directory.getInt(JpegDirectory.TAG_JPEG_DATA_PRECISION));
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void testExtract_NumberOfComponents() throws Exception
{
    assertEquals(3, _directory.getInt(JpegDirectory.TAG_JPEG_NUMBER_OF_COMPONENTS));
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void setUp() throws Exception
{
    _directory = new JpegDirectory();
    _descriptor = new JpegDescriptor(_directory);
}
 

import com.drew.metadata.jpeg.JpegDirectory; //导入依赖的package包/类
public void testGetImageWidthDescription() throws Exception
{
    _directory.setInt(JpegDirectory.TAG_JPEG_IMAGE_WIDTH, 123);
    assertEquals("123 pixels", _descriptor.getImageWidthDescription());
    assertEquals("123 pixels", _directory.getDescription(JpegDirectory.TAG_JPEG_IMAGE_WIDTH));
}