#267: Reads monochrome images with gray ICC profile.

imageio/imageio-core/src/main/java/com/twelvemonkeys/imageio/util/ImageTypeSpecifiers.java

@@ -28,12 +28,14 @@
 
 package com.twelvemonkeys.imageio.util;
 
+import com.twelvemonkeys.lang.Validate;
+
 import javax.imageio.ImageTypeSpecifier;
 import java.awt.color.ColorSpace;
-import java.awt.image.ColorModel;
+import java.awt.image.*;
-import java.awt.image.DataBuffer;
+
-import java.awt.image.DirectColorModel;
+import static com.twelvemonkeys.lang.Validate.isTrue;
-import java.awt.image.IndexColorModel;
+import static com.twelvemonkeys.lang.Validate.notNull;
 
 /**
  * Factory class for creating {@code ImageTypeSpecifier}s.
@@ -59,17 +61,9 @@ public final class ImageTypeSpecifiers {
                                                   final int transferType, boolean isAlphaPremultiplied) {
         if (transferType == DataBuffer.TYPE_BYTE || transferType == DataBuffer.TYPE_USHORT) {
             // ImageTypeSpecifier unconditionally uses bits == 32, we'll use a workaround for BYTE/USHORT types
-            if (colorSpace == null) {
+            notNull(colorSpace, "colorSpace");
-                throw new IllegalArgumentException("colorSpace == null!");
+            isTrue(colorSpace.getType() == ColorSpace.TYPE_RGB, colorSpace, "ColorSpace must be TYPE_RGB");
-            }
+            isTrue(redMask != 0 || greenMask != 0 || blueMask != 0 || alphaMask != 0, "No mask has at least 1 bit set");
-
-            if (colorSpace.getType() != ColorSpace.TYPE_RGB) {
-                throw new IllegalArgumentException("colorSpace is not of type TYPE_RGB!");
-            }
-
-            if (redMask == 0 && greenMask == 0 && blueMask == 0 && alphaMask == 0) {
-                throw new IllegalArgumentException("No mask has at least 1 bit set!");
-            }
 
             int bits = transferType == DataBuffer.TYPE_BYTE ? 8 : 16;
 
@@ -131,6 +125,34 @@ public final class ImageTypeSpecifiers {
         return ImageTypeSpecifier.createGrayscale(bits, dataType, false, isAlphaPremultiplied);
     }
 
+    public static ImageTypeSpecifier createPackedGrayscale(final ColorSpace colorSpace, final int bits, final int dataType) {
+        notNull(colorSpace, "colorSpace");
+        isTrue(colorSpace.getType() == ColorSpace.TYPE_GRAY, colorSpace, "ColorSpace must be TYPE_GRAY");
+        isTrue(bits == 1 || bits == 2 || bits == 4, bits, "bits must be 1, 2, or 4: %s");
+        isTrue(dataType == DataBuffer.TYPE_BYTE, dataType, "dataType must be TYPE_BYTE: %s");
+
+        int numEntries = 1 << bits;
+
+        byte[] arr = new byte[numEntries];
+        byte[] arg = new byte[numEntries];
+        byte[] arb = new byte[numEntries];
+
+        // Scale array values according to color profile..
+        for (int i = 0; i < numEntries; i++) {
+            float[] gray = new float[]{i / (float) (numEntries - 1)};
+            float[] rgb = colorSpace.toRGB(gray);
+
+            arr[i] = (byte) (rgb[0] * 255);
+            arg[i] = (byte) (rgb[1] * 255);
+            arb[i] = (byte) (rgb[2]* 255);
+        }
+
+        ColorModel colorModel = new IndexColorModel(bits, numEntries, arr, arg, arb);
+        SampleModel sampleModel = new MultiPixelPackedSampleModel(dataType, 1, 1, bits);
+
+        return new ImageTypeSpecifier(colorModel, sampleModel);
+    }
+
     public static ImageTypeSpecifier createIndexed(final byte[] redLUT, final byte[] greenLUT,
                                                    final byte[] blueLUT, final byte[] alphaLUT,
                                                    final int bits, final int dataType) {

imageio/imageio-core/src/test/java/com/twelvemonkeys/imageio/util/ImageTypeSpecifiersTest.java

@@ -463,6 +463,30 @@ public class ImageTypeSpecifiersTest {
         );
     }
 
+    @Test
+    public void testCreatePackedGrayscale1() {
+        assertEquals(
+                ImageTypeSpecifier.createGrayscale(1, DataBuffer.TYPE_BYTE, false),
+                ImageTypeSpecifiers.createPackedGrayscale(GRAY, 1, DataBuffer.TYPE_BYTE)
+        );
+    }
+
+    @Test
+    public void testCreatePackedGrayscale2() {
+        assertEquals(
+                ImageTypeSpecifier.createGrayscale(2, DataBuffer.TYPE_BYTE, false),
+                ImageTypeSpecifiers.createPackedGrayscale(GRAY, 2, DataBuffer.TYPE_BYTE)
+        );
+    }
+
+    @Test
+    public void testCreatePackedGrayscale4() {
+        assertEquals(
+                ImageTypeSpecifier.createGrayscale(4, DataBuffer.TYPE_BYTE, false),
+                ImageTypeSpecifiers.createPackedGrayscale(GRAY, 4, DataBuffer.TYPE_BYTE)
+        );
+    }
+
     @Test
     public void testCreateIndexedByteArrays1to8() {
         for (int bits = 1; bits <= 8; bits <<= 1) {

imageio/imageio-tiff/src/main/java/com/twelvemonkeys/imageio/plugins/tiff/TIFFImageReader.java

@@ -364,8 +364,11 @@ public class TIFFImageReader extends ImageReaderBase {
                         if (cs == ColorSpace.getInstance(ColorSpace.CS_GRAY) && (bitsPerSample == 1 || bitsPerSample == 2 || bitsPerSample == 4 || bitsPerSample == 8 || bitsPerSample == 16 || bitsPerSample == 32)) {
                             return ImageTypeSpecifiers.createGrayscale(bitsPerSample, dataType);
                         }
-                        else if (bitsPerSample == 1 || bitsPerSample == 2 || bitsPerSample == 4 || bitsPerSample == 8 || bitsPerSample == 16 || bitsPerSample == 32) {
+                        else if (bitsPerSample == 1 || bitsPerSample == 2 || bitsPerSample == 4 ) {
-                            // TODO: Should use packed format for 1/2/4
+                            // Use packed format for 1/2/4 bits
+                            return ImageTypeSpecifiers.createPackedGrayscale(cs, bitsPerSample, dataType);
+                        }
+                        else if (bitsPerSample == 8 || bitsPerSample == 16 || bitsPerSample == 32) {
                             return ImageTypeSpecifiers.createInterleaved(cs, new int[] {0}, dataType, false, false);
                         }
 

imageio/imageio-tiff/src/test/java/com/twelvemonkeys/imageio/plugins/tiff/TIFFImageReaderTest.java

@@ -90,6 +90,7 @@ public class TIFFImageReaderTest extends ImageReaderAbstractTest<TIFFImageReader
                 new TestData(getClassLoaderResource("/tiff/lzw-rgba-padded-icc.tif"), new Dimension(19, 11)), // RGBA, LZW compression with padded ICC profile
                 new TestData(getClassLoaderResource("/tiff/lzw-rgba-4444.tif"), new Dimension(64, 64)), // RGBA, LZW compression with UINT 4/4/4/4 + gray 2/2
                 new TestData(getClassLoaderResource("/tiff/lzw-buffer-overflow.tif"), new Dimension(5, 49)), // RGBA, LZW compression, will throw IOOBE if small buffer
+                new TestData(getClassLoaderResource("/tiff/scan-mono-iccgray.tif"), new Dimension(2408, 3436)), // B/W, PackBits w/gray ICC profile
                 // CCITT
                 new TestData(getClassLoaderResource("/tiff/ccitt/group3_1d.tif"), new Dimension(6, 4)), // B/W, CCITT T4 1D
                 new TestData(getClassLoaderResource("/tiff/ccitt/group3_1d_fill.tif"), new Dimension(6, 4)), // B/W, CCITT T4 1D