More clean-up: Removed optional flags from param, header size validation, metadata now reports compresion as lossy

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

@@ -72,7 +72,7 @@ public final class IIOUtil {
      */
     public static InputStream createStreamAdapter(final ImageInputStream pStream) {
         // TODO: Include stream start pos?
-        // TODO: Skip buffering for known in-memory implementations?
+        // TODO: Skip buffering for known in-memory implementations? pStream.isCachedMemory
         return new BufferedInputStream(new IIOInputStreamAdapter(pStream));
     }
 
@@ -86,7 +86,7 @@ public final class IIOUtil {
      */
     public static InputStream createStreamAdapter(final ImageInputStream pStream, final long pLength) {
         // TODO: Include stream start pos?
-        // TODO: Skip buffering for known in-memory implementations?
+        // TODO: Skip buffering for known in-memory implementations? pStream.isCachedMemory
         return new BufferedInputStream(new IIOInputStreamAdapter(pStream, pLength));
     }
 

imageio/imageio-dds/src/main/java/com/twelvemonkeys/imageio/plugins/dds/DDS.java

@@ -35,6 +35,7 @@ package com.twelvemonkeys.imageio.plugins.dds;
 interface DDS {
     int MAGIC = ('D' << 24) + ('D' << 16) + ('S' << 8) + ' '; // Big-Endian
     int HEADER_SIZE = 124;
+    int PIXELFORMAT_SIZE = 32;
 
     // Header Flags
     int FLAG_CAPS = 1;              // Required in every .dds file.

imageio/imageio-dds/src/main/java/com/twelvemonkeys/imageio/plugins/dds/DDSHeader.java

@@ -111,6 +111,9 @@ final class DDSHeader {
 
         // DDS_PIXELFORMAT structure
         int px_dwSize = imageInput.readInt(); // [76,79]
+        if (px_dwSize != DDS.PIXELFORMAT_SIZE) {
+            throw new IIOException(String.format("Invalid DDS PIXELFORMAT size (expected %d): %d", DDS.PIXELFORMAT_SIZE, dwSize));
+        }
 
         header.pixelFormatFlags = imageInput.readInt(); // [80,83]
         header.fourCC = imageInput.readInt(); // [84,87]
@@ -243,10 +246,12 @@ final class DDSHeader {
     @Override
     public String toString() {
         return "DDSHeader{" +
-            "flags=" + flags +
+            "flags=" + Integer.toBinaryString(flags) +
             ", mipMapCount=" + mipMapCount +
-            ", dimensions=" + Arrays.toString(dimensions) +
+            ", dimensions=" + Arrays.toString(Arrays.stream(dimensions)
-            ", pixelFormatFlags=" + pixelFormatFlags +
+                                                    .map(DDSHeader::dimensionToString)
+                                                    .toArray(String[]::new)) +
+            ", pixelFormatFlags=" + Integer.toBinaryString(pixelFormatFlags) +
             ", fourCC=" + fourCC +
             ", bitCount=" + bitCount +
             ", redMask=" + redMask +
@@ -255,4 +260,8 @@ final class DDSHeader {
             ", alphaMask=" + alphaMask +
             '}';
     }
+
+    private static String dimensionToString(Dimension dimension) {
+        return String.format("%dx%d", dimension.width, dimension.height);
+    }
 }

imageio/imageio-dds/src/main/java/com/twelvemonkeys/imageio/plugins/dds/DDSImageDataEncoder.java

@@ -13,15 +13,11 @@ import static com.twelvemonkeys.imageio.plugins.dds.DDSReader.RGB_16_ORDER;
 
 /**
  * A designated class to encode image data to binary.
- * <p>
+ *
- * References:
+ * @see <a href="https://www.ludicon.com/castano/blog/2009/03/gpu-dxt-decompression/">GPU DXT Decompression</a>.
- * <p>
+ * @see <a href="https://sv-journal.org/2014-1/06/en/index.php">TEXTURE COMPRESSION TECHNIQUES</a>.
- * [1] <a href="https://www.ludicon.com/castano/blog/2009/03/gpu-dxt-decompression/">GPU DXT Decompression</a>.
+ * @see <a href="https://mrelusive.com/publications/papers/Real-Time-Dxt-Compression.pdf">Real-Time DXT Compression by J.M.P. van Waveren</a>
- * [2] <a href="https://sv-journal.org/2014-1/06/en/index.php">TEXTURE COMPRESSION TECHNIQUES</a>.
+ * @see <a href="https://registry.khronos.org/DataFormat/specs/1.4/dataformat.1.4.pdf">Khronos Data Format Specification v1.4 by Andrew Garrard</a>
- * [3] <a href="https://mrelusive.com/publications/papers/Real-Time-Dxt-Compression.pdf">Real-Time DXT Compression by J.M.P. van Waveren</a>
- * [4] <a href="https://registry.khronos.org/DataFormat/specs/1.4/dataformat.1.4.pdf">Khronos Data Format Specification v1.4 by Andrew Garrard</a>
- * </p>
- * </p>
  */
 class DDSImageDataEncoder {
     private DDSImageDataEncoder() {}
@@ -32,7 +28,7 @@ class DDSImageDataEncoder {
     private static final int BC4_CHANNEL_GREEN = 1; //same re-usage as BC3 but for green channel BC5 uses
 
     static void writeImageData(ImageOutputStream imageOutput, RenderedImage renderedImage, BlockCompression compression) throws IOException {
-        // TODO: compression == null for custom RGB data?
+        // TODO: Support compression == null for uncompressed RGB(A/X) data?
 
         switch (compression) {
             case BC1:

imageio/imageio-dds/src/main/java/com/twelvemonkeys/imageio/plugins/dds/DDSImageMetadata.java

@@ -39,6 +39,7 @@ final class DDSImageMetadata extends StandardImageMetadataSupport {
     DDSImageMetadata(ImageTypeSpecifier specifier, DDSType type) {
         super(builder(specifier)
             .withCompressionTypeName(compressionName(type))
+            .withCompressionLossless(!type.isBlockCompression())
             .withBitsPerSample(bitsPerSample(type))
             .withFormatVersion("1.0")
         );

imageio/imageio-dds/src/main/java/com/twelvemonkeys/imageio/plugins/dds/DDSImageReader.java

@@ -101,6 +101,11 @@ public final class DDSImageReader extends ImageReaderBase {
             return ImageTypeSpecifiers.createFromBufferedImageType(BufferedImage.TYPE_INT_RGB);
         }
 
+        // TODO: DXT1 can have 1 bit alpha, usually don't...
+        //  DXT3/5 have alpha
+        //  DXT2/4 ...?
+
+
         return ImageTypeSpecifiers.createFromBufferedImageType(BufferedImage.TYPE_INT_ARGB);
     }
 
@@ -161,9 +166,11 @@ public final class DDSImageReader extends ImageReaderBase {
 
     private void readHeader() throws IOException {
         if (header == null) {
-            imageInput.setByteOrder(ByteOrder.LITTLE_ENDIAN);
+            imageInput.setByteOrder(ByteOrder.LITTLE_ENDIAN); // TODO: Move to setInput?
             header = DDSHeader.read(imageInput);
             imageInput.flushBefore(imageInput.getStreamPosition());
+
+            System.out.println("header = " + header);
         }
 
         imageInput.seek(imageInput.getFlushedPosition());

imageio/imageio-dds/src/main/java/com/twelvemonkeys/imageio/plugins/dds/DDSImageWriteParam.java

@@ -22,38 +22,12 @@ public final class DDSImageWriteParam extends ImageWriteParam {
         return compressionTypes.toArray(new String[0]);
     }
 
-    private int optionalBitFlags;
     private boolean writeDXT10;
 
     DDSImageWriteParam() {
         canWriteCompressed = true;
         compressionTypes = COMPRESSION_TYPES;
         compressionType = DEFAULT_TYPE.name();
-        setLinearSize();
-    }
-
-    // TODO: Set this always for compressed images?
-    public void setLinearSize() {
-        optionalBitFlags |= DDS.FLAG_LINEARSIZE;
-    }
-
-    public void clearLinearSize() {
-        optionalBitFlags &= ~DDS.FLAG_LINEARSIZE;
-    }
-
-    // TODO: Set this always for uncompressed images?
-    public void setPitch() {
-        optionalBitFlags |= DDS.FLAG_PITCH;
-    }
-
-    public void clearPitch() {
-        optionalBitFlags &= ~DDS.FLAG_PITCH;
-    }
-
-    // TODO: Other flags?
-
-    public int optionalBitFlags() {
-        return optionalBitFlags;
     }
 
     public void setWriteDX10() {

imageio/imageio-dds/src/main/java/com/twelvemonkeys/imageio/plugins/dds/DDSImageWriter.java

@@ -35,6 +35,10 @@ class DDSImageWriter extends ImageWriterBase {
         return new DDSImageWriteParam();
     }
 
+    // TODO: Suppport MipMaps using sequence methods
+    //  This involves seeking backwards, updating the mipmap flag and mipmapcount in the header... :-/
+    //   + ensuring that each level is half the size of the previous, but still a multiple of 4...
+
     @Override
     public void write(IIOMetadata streamMetadata, IIOImage image, ImageWriteParam param) throws IOException {
         assertOutput();
@@ -52,7 +56,7 @@ class DDSImageWriter extends ImageWriterBase {
         imageOutput.writeInt(DDS.MAGIC);
         imageOutput.setByteOrder(ByteOrder.LITTLE_ENDIAN);
 
-        writeHeader(image, ddsParam.type(), ddsParam.isWriteDXT10(), ddsParam.optionalBitFlags());
+        writeHeader(image, ddsParam.type(), ddsParam.isWriteDXT10());
         if (ddsParam.isWriteDXT10()) {
             writeDXT10Header(ddsParam.getDxgiFormat());
         }
@@ -96,9 +100,10 @@ class DDSImageWriter extends ImageWriterBase {
         }
     }
 
-    private void writeHeader(IIOImage image, DDSType type, boolean writeDXT10, int optionalBitFlags) throws IOException {
+    private void writeHeader(IIOImage image, DDSType type, boolean writeDXT10) throws IOException {
         imageOutput.writeInt(DDS.HEADER_SIZE);
-        imageOutput.writeInt(DDS.FLAG_CAPS | DDS.FLAG_HEIGHT | DDS.FLAG_WIDTH | DDS.FLAG_PIXELFORMAT | optionalBitFlags);
+        int linearSizeOrPitch = type.isBlockCompression() ? DDS.FLAG_LINEARSIZE : DDS.FLAG_PITCH;
+        imageOutput.writeInt(DDS.FLAG_CAPS | DDS.FLAG_HEIGHT | DDS.FLAG_WIDTH | DDS.FLAG_PIXELFORMAT | linearSizeOrPitch);
 
         RenderedImage renderedImage = image.getRenderedImage();
         int height = renderedImage.getHeight();
@@ -182,7 +187,8 @@ class DDSImageWriter extends ImageWriterBase {
     private void writePixelFormatFlags(DDSType type, boolean writeDXT10) throws IOException {
         if (writeDXT10 || type.isFourCC()) {
             imageOutput.writeInt(DDS.PIXEL_FORMAT_FLAG_FOURCC);
-        } else {
+        }
+        else {
             imageOutput.writeInt(DDS.PIXEL_FORMAT_FLAG_RGB | (type.rgbaMasks != null ? DDS.PIXEL_FORMAT_FLAG_ALPHAPIXELS : 0));
         }
     }
@@ -190,7 +196,8 @@ class DDSImageWriter extends ImageWriterBase {
     private void writePitchOrLinearSize(int height, int width, DDSType type) throws IOException {
         if (type.isBlockCompression()) {
             imageOutput.writeInt(((width + 3) / 4) * ((height + 3) / 4) * type.blockSize());
-        } else {
+        }
+        else {
             imageOutput.writeInt(width * type.blockSize());
         }
     }

imageio/imageio-dds/src/test/java/com/twelvemonkeys/imageio/plugins/dds/DDSImageMetadataTest.java

@@ -17,13 +17,16 @@ class DDSImageMetadataTest {
         DDSImageMetadata metadata = createDDSImageMetadata(BufferedImage.TYPE_INT_ARGB, DDSType.DXT1);
         IIOMetadataNode tree = (IIOMetadataNode) metadata.getAsTree(IIOMetadataFormatImpl.standardMetadataFormatName);
 
-        NodeList compressions = tree.getElementsByTagName("CompressionTypeName");
+        NodeList compressionTypeNames = tree.getElementsByTagName("CompressionTypeName");
-        assertEquals(1, compressions.getLength());
+        assertEquals(1, compressionTypeNames.getLength());
+        IIOMetadataNode compressionTypeName = (IIOMetadataNode) compressionTypeNames.item(0);
+        assertEquals("DXT1", compressionTypeName.getAttribute("value"));
 
-        IIOMetadataNode compression = (IIOMetadataNode) compressions.item(0);
+        NodeList losslesses = tree.getElementsByTagName("Lossless");
-        assertEquals("DXT1", compression.getAttribute("value"));
+        assertEquals(1, losslesses.getLength());
+        IIOMetadataNode lossless = (IIOMetadataNode) losslesses.item(0);
+        assertEquals("FALSE", lossless.getAttribute("value"));
 
-        // TODO: This should probably not have alpha...
         NodeList alphas = tree.getElementsByTagName("Alpha");
         assertEquals(1, alphas.getLength());
         IIOMetadataNode alpha = (IIOMetadataNode) alphas.item(0);