Merge pull request #131 from dbmdz/jpg-grayscale-numcomps

Fix getImageTypes() implementations on readers (fixes #129)

imageio-openjpeg/src/main/java/de/digitalcollections/openjpeg/Info.java

@@ -1,5 +1,6 @@
 package de.digitalcollections.openjpeg;
 
+import de.digitalcollections.openjpeg.lib.enums.COLOR_SPACE;
 import java.awt.Dimension;
 import java.awt.Point;
 import java.util.Arrays;
@@ -19,6 +20,8 @@ public class Info {
   private int numTilesY;
   private int width;
   private int height;
+  private int bitsPerPixel;
+  private COLOR_SPACE colorSpace;
 
   void setNumComponents(int numComponents) {
     this.numComponents = numComponents;
@@ -60,6 +63,14 @@ public void setTileOriginY(int tileOriginY) {
     this.tileOriginY = tileOriginY;
   }
 
+  public void setBitsPerPixel(int bitsPerPixel) {
+    this.bitsPerPixel = bitsPerPixel;
+  }
+
+  public void setColorSpace(COLOR_SPACE colorSpace) {
+    this.colorSpace = colorSpace;
+  }
+
   public int getNumComponents() {
     return numComponents;
   }
@@ -113,4 +124,12 @@ public List<Dimension> getAvailableTileSizes() {
                 new Dimension((int) (this.tileWidth / factor), (int) (this.tileHeight / factor)))
         .collect(Collectors.toList());
   }
+
+  public int getBitsPerPixel() {
+    return bitsPerPixel;
+  }
+
+  public COLOR_SPACE getColorSpace() {
+    return colorSpace;
+  }
 }

imageio-openjpeg/src/main/java/de/digitalcollections/openjpeg/OpenJpeg.java

@@ -44,6 +44,13 @@ public class OpenJpeg {
   @SuppressWarnings("checkstyle:constantname")
   private static final opj_msg_callback errorLogFn = (msg, data) -> LOGGER.error(msg.trim());
 
+  public static final ColorModel COLOR_MODEL_CMYK =
+      new ComponentColorModel(
+          new CMYKColorSpace(), false, false, Transparency.TRANSLUCENT, DataBuffer.TYPE_BYTE);
+  public static final ColorModel COLOR_MODEL_CMYK_ALPHA =
+      new ComponentColorModel(
+          new CMYKColorSpace(), true, false, Transparency.TRANSLUCENT, DataBuffer.TYPE_BYTE);
+
   public libopenjp2 lib;
   public Runtime runtime;
 
@@ -138,6 +145,8 @@ private Info getInfo(Pointer codecPointer, opj_image img) {
       info.setTileOriginX(csInfo.tx0.intValue());
       info.setTileOriginY(csInfo.ty0.intValue());
       info.setNumResolutions(csInfo.m_default_tile_info.tccp_info.get().numresolutions.intValue());
+      info.setBitsPerPixel(img.comps.get().bpp.intValue());
+      info.setColorSpace(img.color_space.get());
 
       return info;
     } finally {
@@ -379,9 +388,7 @@ private BufferedImage decode(Pointer stream, Rectangle area, int reduceFactor)
   private BufferedImage decodeCMYK(
       int width, int height, int numcomps, int colorDepthFactor, opj_image_comp[] comps) {
     boolean hasAlpha = numcomps > 4;
-    ColorModel colorModel =
-        new ComponentColorModel(
-            new CMYKColorSpace(), hasAlpha, false, Transparency.TRANSLUCENT, DataBuffer.TYPE_BYTE);
+    ColorModel colorModel = hasAlpha ? COLOR_MODEL_CMYK_ALPHA : COLOR_MODEL_CMYK;
     BufferedImage bufImg =
         new BufferedImage(
             colorModel, colorModel.createCompatibleWritableRaster(width, height), false, null);

imageio-openjpeg/src/main/java/de/digitalcollections/openjpeg/imageio/OpenJp2ImageReader.java

@@ -2,11 +2,12 @@
 
 import de.digitalcollections.openjpeg.Info;
 import de.digitalcollections.openjpeg.OpenJpeg;
+import de.digitalcollections.openjpeg.lib.enums.COLOR_SPACE;
 import java.awt.Rectangle;
 import java.awt.image.BufferedImage;
 import java.io.IOException;
-import java.util.Collections;
 import java.util.Iterator;
+import java.util.stream.Stream;
 import javax.imageio.ImageReadParam;
 import javax.imageio.ImageReader;
 import javax.imageio.ImageTypeSpecifier;
@@ -104,10 +105,38 @@ public int getHeight(int imageIndex) throws IOException {
   @Override
   public Iterator<ImageTypeSpecifier> getImageTypes(int imageIndex) throws IOException {
     checkIndex(imageIndex);
-    // TODO: Support grayscale?
-    return Collections.singletonList(
-            ImageTypeSpecifier.createFromBufferedImageType(BufferedImage.TYPE_3BYTE_BGR))
-        .iterator();
+    int numComps = info.getNumComponents();
+    ImageTypeSpecifier spec = null;
+    if (numComps == 3) {
+      spec = ImageTypeSpecifier.createFromBufferedImageType(BufferedImage.TYPE_3BYTE_BGR);
+    } else if (numComps == 2) {
+      spec = ImageTypeSpecifier.createFromBufferedImageType(BufferedImage.TYPE_4BYTE_ABGR);
+    } else if (numComps == 4) {
+      if (info.getColorSpace() == COLOR_SPACE.OPJ_CLRSPC_CMYK) {
+        spec =
+            new ImageTypeSpecifier(
+                OpenJpeg.COLOR_MODEL_CMYK_ALPHA,
+                OpenJpeg.COLOR_MODEL_CMYK_ALPHA.createCompatibleSampleModel(
+                    info.getNativeSize().width, info.getNativeSize().height));
+      }
+      spec = ImageTypeSpecifier.createFromBufferedImageType(BufferedImage.TYPE_4BYTE_ABGR);
+    } else if (numComps == 1) {
+      spec =
+          ImageTypeSpecifier.createFromBufferedImageType(
+              info.getBitsPerPixel() > 1
+                  ? BufferedImage.TYPE_BYTE_GRAY
+                  : BufferedImage.TYPE_BYTE_BINARY);
+    } else if (numComps == 5) {
+      spec =
+          new ImageTypeSpecifier(
+              OpenJpeg.COLOR_MODEL_CMYK,
+              OpenJpeg.COLOR_MODEL_CMYK.createCompatibleSampleModel(
+                  info.getNativeSize().width, info.getNativeSize().height));
+    }
+    if (spec == null) {
+      return Stream.<ImageTypeSpecifier>empty().iterator();
+    }
+    return Stream.of(spec).iterator();
   }
 
   private Rectangle adjustRegion(int imageIndex, Rectangle sourceRegion) throws IOException {

imageio-openjpeg/src/test/java/de/digitalcollections/openjpeg/imageio/OpenJp2ImageReaderTest.java

@@ -171,7 +171,7 @@ public void testReadGrayWithAlpha() throws Exception {
 
   @Test
   public void testReadGray16bitWithoutAlpha() throws Exception {
-      assertImageEquals("gray16bitWithoutAlpha.png", "gray16bitWithoutAlpha.jp2");
+    assertImageEquals("gray16bitWithoutAlpha.png", "gray16bitWithoutAlpha.jp2");
   }
 
   @Test

imageio-turbojpeg/src/main/java/de/digitalcollections/turbojpeg/imageio/TurboJpegImageReader.java

@@ -1,13 +1,12 @@
 package de.digitalcollections.turbojpeg.imageio;
 
 import static java.awt.image.BufferedImage.TYPE_3BYTE_BGR;
-import static java.awt.image.BufferedImage.TYPE_4BYTE_ABGR;
-import static java.awt.image.BufferedImage.TYPE_4BYTE_ABGR_PRE;
 import static java.awt.image.BufferedImage.TYPE_BYTE_GRAY;
 
 import de.digitalcollections.turbojpeg.Info;
 import de.digitalcollections.turbojpeg.TurboJpeg;
 import de.digitalcollections.turbojpeg.TurboJpegException;
+import de.digitalcollections.turbojpeg.lib.enums.TJCS;
 import java.awt.Dimension;
 import java.awt.Rectangle;
 import java.awt.image.BufferedImage;
@@ -111,9 +110,11 @@ public int getHeight(int imageIndex) throws IOException {
 
   @Override
   public Iterator<ImageTypeSpecifier> getImageTypes(int imageIndex) throws IOException {
-    return Stream.of(TYPE_3BYTE_BGR, TYPE_4BYTE_ABGR, TYPE_4BYTE_ABGR_PRE, TYPE_BYTE_GRAY)
-        .map(ImageTypeSpecifier::createFromBufferedImageType)
-        .iterator();
+    return Stream.of(
+        ImageTypeSpecifier.createFromBufferedImageType(
+            info.getColorspace() == TJCS.TJCS_GRAY ? TYPE_BYTE_GRAY : TYPE_3BYTE_BGR
+        )
+    ).iterator();
   }
 
   /**

imageio-turbojpeg/src/test/java/de/digitalcollections/turbojpeg/imageio/BufferedImageAssert.java

@@ -1,5 +1,7 @@
 package de.digitalcollections.turbojpeg.imageio;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 import java.awt.image.BufferedImage;
 import java.io.File;
 import java.io.IOException;
@@ -52,4 +54,27 @@ public BufferedImageAssert hasDimensions(int width, int height) {
     }
     return this;
   }
+
+  public BufferedImageAssert isEqualTo(BufferedImage other) {
+    int width = other.getWidth();
+    assertEquals(width, actual.getWidth());
+    int height = other.getHeight();
+    assertEquals(height, actual.getHeight());
+    for (int x = 0; x < width; x++) {
+      for (int y = 0; y < height; y++) {
+        int expectedPixel = other.getRGB(x, y);
+        int actualPixel = actual.getRGB(x, y);
+        if (expectedPixel >> 24 == 0 && actualPixel >> 24 == 0) {
+          // transparent
+          continue;
+        }
+        if (expectedPixel != actualPixel) {
+          failWithMessage(
+              "Expected pixel with color '%s' at x=%d, y=%d, got '%s'",
+              expectedPixel, x, y, actualPixel);
+        }
+      }
+    }
+    return this;
+  }
 }

imageio-turbojpeg/src/test/java/de/digitalcollections/turbojpeg/imageio/TurboJpegImageReaderTest.java

@@ -8,6 +8,7 @@
 import java.awt.image.BufferedImage;
 import java.io.File;
 import java.io.IOException;
+import java.io.InputStream;
 import java.util.List;
 import java.util.function.Supplier;
 import javax.imageio.ImageIO;
@@ -267,4 +268,17 @@ void testAdjustMCURegion() {
     assertThat(region).isEqualTo(regionExpected);
     assertThat(extraCrop).isEqualTo(extraCropExpected);
   }
+
+  @Test
+  public void testReadGrayscale() throws IOException {
+    ImageReader reader = getReader("grayscale.jpg");
+    assertThat(reader.getRawImageType(0).getNumComponents()).isEqualTo(1);
+    TurboJpegImageReadParam param = (TurboJpegImageReadParam) reader.getDefaultReadParam();
+    BufferedImage img = reader.read(0, param);
+    assertThat(img).hasDimensions(1955, 524);
+    assertThat(img.getType()).isEqualTo(BufferedImage.TYPE_BYTE_GRAY);
+    InputStream input = ClassLoader.getSystemResourceAsStream("grayscale_control.png");
+    BufferedImage controlImg = ImageIO.read(input);
+    assertThat(img).isEqualTo(controlImg);
+  }
 }

imageio-turbojpeg/src/test/java/de/digitalcollections/turbojpeg/imageio/TurboJpegImageWriterTest.java

@@ -1,13 +1,15 @@
 package de.digitalcollections.turbojpeg.imageio;
 
-import static org.assertj.core.api.Assertions.assertThat;
+import static de.digitalcollections.turbojpeg.imageio.CustomAssertions.assertThat;
 
 import com.google.common.collect.Lists;
 import com.google.common.collect.Streams;
 import java.awt.image.BufferedImage;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
 import javax.imageio.IIOImage;
 import javax.imageio.ImageIO;
 import javax.imageio.ImageWriteParam;
@@ -102,4 +104,28 @@ public void testCanReuseWriter() throws IOException {
 
     assertThat(rgb.toByteArray()).isNotEqualTo(bw.toByteArray());
   }
+
+  @Test
+  public void testEncodeGrayscale() throws IOException {
+    ImageWriter writer =
+        Streams.stream(ImageIO.getImageWritersByFormatName("jpeg"))
+            .filter(TurboJpegImageWriter.class::isInstance)
+            .findFirst()
+            .get();
+    ImageWriteParam param = writer.getDefaultWriteParam();
+    param.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
+    param.setCompressionQuality(0.85f);
+    BufferedImage in = ImageIO.read(ClassLoader.getSystemResource("grayscale.jpg"));
+    ByteArrayOutputStream os = new ByteArrayOutputStream();
+    try (ImageOutputStream ios = ImageIO.createImageOutputStream(os)) {
+      writer.setOutput(ios);
+      writer.write(null, new IIOImage(in, null, null), param);
+    }
+    os.flush();
+    Files.write(Paths.get("/tmp/debug.jpg"), os.toByteArray());
+    assertThat(os.toByteArray()).isNotEmpty();
+    ByteArrayInputStream bis = new ByteArrayInputStream(os.toByteArray());
+    BufferedImage jpegImg = ImageIO.read(bis);
+    assertThat(jpegImg).hasNoPixelsOfColor(255);
+  }
 }