ImageUtilsAwt.java

   1 package be.nikiroo.utils.ui;
   2
   3 import java.awt.geom.AffineTransform;
   4 import java.awt.image.AffineTransformOp;
   5 import java.awt.image.BufferedImage;
   6 import java.io.ByteArrayInputStream;
   7 import java.io.File;
   8 import java.io.IOException;
   9 import java.io.InputStream;
  10
  11 import javax.imageio.ImageIO;
  12
  13 import be.nikiroo.utils.Image;
  14 import be.nikiroo.utils.ImageUtils;
  15
  16 /**
  17  * This class offer some utilities based around images and uses java.awt.
  18  *
  19  * @author niki
  20  */
  21 public class ImageUtilsAwt extends ImageUtils {
  22         @Override
  23         public void saveAsImage(Image img, File target, String format)
  24                         throws IOException {
  25                 try {
  26                         BufferedImage image = fromImage(img);
  27
  28                         boolean ok = false;
  29                         try {
  30
  31                                 ok = ImageIO.write(image, format, target);
  32                         } catch (IOException e) {
  33                                 ok = false;
  34                         }
  35
  36                         // Some formats are not reliable
  37                         // Second chance: PNG
  38                         if (!ok && !format.equals("png")) {
  39                                 try {
  40                                         ok = ImageIO.write(image, "png", target);
  41                                 } catch (IllegalArgumentException e) {
  42                                         throw e;
  43                                 } catch (Exception e) {
  44                                         throw new IOException("Undocumented exception occured, "
  45                                                         + "converting to IOException", e);
  46                                 }
  47                         }
  48
  49                         if (!ok) {
  50                                 throw new IOException(
  51                                                 "Cannot find a writer for this image and format: "
  52                                                                 + format);
  53                         }
  54                 } catch (IOException e) {
  55                         throw new IOException("Cannot write image to " + target, e);
  56                 }
  57         }
  58
  59         /**
  60          * Convert the given {@link Image} into a {@link BufferedImage} object,
  61          * respecting the EXIF transformations if any.
  62          *
  63          * @param img
  64          *            the {@link Image}
  65          *
  66          * @return the {@link Image} object
  67          *
  68          * @throws IOException
  69          *             in case of IO error
  70          */
  71         public static BufferedImage fromImage(Image img) throws IOException {
  72                 InputStream in = new ByteArrayInputStream(img.getData());
  73
  74                 int orientation;
  75                 try {
  76                         orientation = getExifTransorm(in);
  77                 } catch (Exception e) {
  78                         // no EXIF transform, ok
  79                         orientation = -1;
  80                 }
  81
  82                 in.reset();
  83                 BufferedImage image = ImageIO.read(in);
  84
  85                 if (image == null) {
  86                         throw new IOException("Failed to convert input to image");
  87                 }
  88
  89                 // Note: this code has been found on Internet;
  90                 // thank you anonymous coder.
  91                 int width = image.getWidth();
  92                 int height = image.getHeight();
  93                 AffineTransform affineTransform = new AffineTransform();
  94
  95                 switch (orientation) {
  96                 case 1:
  97                         affineTransform = null;
  98                         break;
  99                 case 2: // Flip X
 100                         affineTransform.scale(-1.0, 1.0);
 101                         affineTransform.translate(-width, 0);
 102                         break;
 103                 case 3: // PI rotation
 104                         affineTransform.translate(width, height);
 105                         affineTransform.rotate(Math.PI);
 106                         break;
 107                 case 4: // Flip Y
 108                         affineTransform.scale(1.0, -1.0);
 109                         affineTransform.translate(0, -height);
 110                         break;
 111                 case 5: // - PI/2 and Flip X
 112                         affineTransform.rotate(-Math.PI / 2);
 113                         affineTransform.scale(-1.0, 1.0);
 114                         break;
 115                 case 6: // -PI/2 and -width
 116                         affineTransform.translate(height, 0);
 117                         affineTransform.rotate(Math.PI / 2);
 118                         break;
 119                 case 7: // PI/2 and Flip
 120                         affineTransform.scale(-1.0, 1.0);
 121                         affineTransform.translate(-height, 0);
 122                         affineTransform.translate(0, width);
 123                         affineTransform.rotate(3 * Math.PI / 2);
 124                         break;
 125                 case 8: // PI / 2
 126                         affineTransform.translate(0, width);
 127                         affineTransform.rotate(3 * Math.PI / 2);
 128                         break;
 129                 default:
 130                         affineTransform = null;
 131                         break;
 132                 }
 133
 134                 if (affineTransform != null) {
 135                         AffineTransformOp affineTransformOp = new AffineTransformOp(
 136                                         affineTransform, AffineTransformOp.TYPE_BILINEAR);
 137
 138                         BufferedImage transformedImage = new BufferedImage(width, height,
 139                                         image.getType());
 140                         transformedImage = affineTransformOp
 141                                         .filter(image, transformedImage);
 142
 143                         image = transformedImage;
 144                 }
 145                 //
 146
 147                 return image;
 148         }
 149 }