diff options
Diffstat (limited to 'pdf-over-commons/src/main/java/at/asit/pdfover/commons')
-rw-r--r-- | pdf-over-commons/src/main/java/at/asit/pdfover/commons/utils/ImageUtil.java | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/pdf-over-commons/src/main/java/at/asit/pdfover/commons/utils/ImageUtil.java b/pdf-over-commons/src/main/java/at/asit/pdfover/commons/utils/ImageUtil.java new file mode 100644 index 00000000..a8740317 --- /dev/null +++ b/pdf-over-commons/src/main/java/at/asit/pdfover/commons/utils/ImageUtil.java @@ -0,0 +1,147 @@ +package at.asit.pdfover.commons.utils; + +import java.awt.Graphics2D; +import java.awt.image.BufferedImage; +import java.io.File; +import java.io.IOException; +import java.util.Iterator; + +import javax.imageio.ImageIO; +import javax.imageio.ImageReadParam; +import javax.imageio.ImageReader; +import javax.imageio.stream.ImageInputStream; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import com.drew.imaging.ImageMetadataReader; +import com.drew.imaging.ImageProcessingException; +import com.drew.metadata.Metadata; +import com.drew.metadata.MetadataException; +import com.drew.metadata.exif.ExifDirectoryBase; +import com.drew.metadata.exif.ExifIFD0Directory; + +class EXIFRotation { + private static final Logger log = LoggerFactory.getLogger(EXIFRotation.class); + /** + * rotate by this times Math.PI / 2 + */ + final int rotationInQuarters; + /** + * whether you should mirror (left-right) the image AFTER rotation + */ + final boolean shouldMirrorLR; + + private EXIFRotation(int rotateQuarters, boolean mirrorLR) { + this.rotationInQuarters = rotateQuarters; + this.shouldMirrorLR = mirrorLR; + } + + public static final EXIFRotation NONE = new EXIFRotation(0, false); + + private static final EXIFRotation[] rotationForIndex = { + /* invalid (0) */ NONE, + /* 1 */ NONE, + /* 2 */ new EXIFRotation(0, true), + /* 3 */ new EXIFRotation(2, false), + /* 4 */ new EXIFRotation(2, true), + /* 5 */ new EXIFRotation(1, true), + /* 6 */ new EXIFRotation(1, false), + /* 7 */ new EXIFRotation(3, true), + /* 8 */ new EXIFRotation(3, false) + }; + + static EXIFRotation For(File file) throws IOException + { + try + { + Metadata metadata = ImageMetadataReader.readMetadata(file); + if (metadata == null) + return NONE; + ExifIFD0Directory metaDir = metadata.getFirstDirectoryOfType(ExifIFD0Directory.class); + if (metaDir == null) + return NONE; + int orientation = metaDir.getInt(ExifDirectoryBase.TAG_ORIENTATION); + if (rotationForIndex.length <= orientation) + { + log.warn("Invalid orientation {} in EXIF metadata for {}", orientation, file.getName()); + return NONE; + } + return rotationForIndex[orientation]; + } catch (ImageProcessingException | MetadataException e) { + log.error("Failed to read EXIF metadata for {}", file.getName(), e); + return NONE; + } + } +} + +public final class ImageUtil { + + /** + * ImageIO.read, except it honors EXIF rotation metadata + * (which the default, for some reason, does not) + */ + public static final BufferedImage readImageWithEXIFRotation(File input) throws IOException + { + if (input == null) + throw new IllegalArgumentException("input == null"); + if (!input.canRead()) + throw new IllegalArgumentException("cannot read input"); + + ImageInputStream stream = ImageIO.createImageInputStream(input); + if (stream == null) + throw new RuntimeException("Failed to create ImageInputStream for some reason?"); + + Iterator<ImageReader> iter = ImageIO.getImageReaders(stream); + if (!iter.hasNext()) + { + stream.close(); + return null; + } + + ImageReader reader = iter.next(); + boolean isJPEG = reader.getFormatName().equals("JPEG"); + ImageReadParam param = reader.getDefaultReadParam(); + reader.setInput(stream, true, false); + BufferedImage image; + try { + image = reader.read(0, param); + } finally { + reader.dispose(); + stream.close(); + } + + if (!isJPEG) + return image; + + EXIFRotation rotation = EXIFRotation.For(input); + if (rotation.rotationInQuarters > 0) + { + boolean isSideways = ((rotation.rotationInQuarters % 2) == 1); + int sourceWidth = image.getWidth(); + int sourceHeight = image.getHeight(); + int targetWidth = isSideways ? sourceHeight : sourceWidth; + int targetHeight = isSideways ? sourceWidth : sourceHeight; + + BufferedImage result = new BufferedImage(targetWidth, targetHeight, image.getType()); + Graphics2D g = result.createGraphics(); + g.translate((targetWidth - sourceWidth)/2, (targetHeight - sourceHeight)/2); + g.rotate(rotation.rotationInQuarters * Math.PI / 2, sourceWidth/2, sourceHeight/2); + g.drawRenderedImage(image, null); + g.dispose(); + image = result; + } + + if (rotation.shouldMirrorLR) + { + int width = image.getWidth(); + int height = image.getHeight(); + BufferedImage result = new BufferedImage(width, height, image.getType()); + Graphics2D g = result.createGraphics(); + g.drawImage(image, width, 0, -width, height, null); + g.dispose(); + image = result; + } + return image; + } +} |