#483 Initial PSD Write support

2026-05-28 00:00:03 -04:00 · 2021-05-06 00:01:54 +02:00
parent 7ae2d636dc
commit 15a9ad0a9b
19 changed files with 957 additions and 132 deletions
@@ -0,0 +1,122 @@
+package com.twelvemonkeys.imageio.util;
+
+import java.awt.*;
+import java.awt.image.*;
+
+import static com.twelvemonkeys.lang.Validate.notNull;
+
+/**
+ * A class containing various raster utility methods.
+ */
+public final class RasterUtils {
+
+    private RasterUtils() {
+    }
+
+    /**
+     * Returns a raster with {@code DataBuffer.TYPE_BYTE} transfer type.
+     * Works for any raster from a {@code BufferedImage.TYPE_INT_*} image
+     *
+     * @param raster a {@code Raster} with either transfer type {@code DataBuffer.TYPE_BYTE}
+     *               or {@code DataBuffer.TYPE_INT} with `SinglePixelPackedSampleModel`, not {@code null}.
+     * @return a raster with {@code DataBuffer.TYPE_BYTE} transfer type.
+     * @throws IllegalArgumentException if {@code raster} does not have transfer type {@code DataBuffer.TYPE_BYTE}
+     * or {@code DataBuffer.TYPE_INT} with `SinglePixelPackedSampleModel`
+     * @throws NullPointerException if {@code raster} is {@code null}.
+     */
+    public static Raster asByteRaster(final Raster raster) {
+        return asByteRaster0(raster);
+    }
+
+    /**
+     * Returns a writable raster with {@code DataBuffer.TYPE_BYTE} transfer type.
+     * Works for any raster from a {@code BufferedImage.TYPE_INT_*} image.
+     *
+     * @param raster a {@code WritableRaster} with either transfer type {@code DataBuffer.TYPE_BYTE}
+     *               or {@code DataBuffer.TYPE_INT} with `SinglePixelPackedSampleModel`, not {@code null}.
+     * @return a writable raster with {@code DataBuffer.TYPE_BYTE} transfer type.
+     * @throws IllegalArgumentException if {@code raster} does not have transfer type {@code DataBuffer.TYPE_BYTE}
+     * or {@code DataBuffer.TYPE_INT} with `SinglePixelPackedSampleModel`
+     * @throws NullPointerException if {@code raster} is {@code null}.
+     */
+    public static WritableRaster asByteRaster(final WritableRaster raster) {
+        return (WritableRaster) asByteRaster0(raster);
+    }
+
+    private static Raster asByteRaster0(final Raster raster) {
+        switch (raster.getTransferType()) {
+            case DataBuffer.TYPE_BYTE:
+                return raster;
+            case DataBuffer.TYPE_INT:
+                SampleModel sampleModel = raster.getSampleModel();
+
+                if (!(sampleModel instanceof SinglePixelPackedSampleModel)) {
+                    throw new IllegalArgumentException(String.format("Requires SinglePixelPackedSampleModel, %s not supported", sampleModel.getClass().getSimpleName()));
+                }
+
+                final int bands = 4;
+                final DataBufferInt buffer = (DataBufferInt) raster.getDataBuffer();
+
+                int w = raster.getWidth();
+                int h = raster.getHeight();
+                int size = buffer.getSize();
+
+                return new WritableRaster(
+                        new PixelInterleavedSampleModel(DataBuffer.TYPE_BYTE, w, h, bands, w * bands, createBandOffsets((SinglePixelPackedSampleModel) sampleModel)),
+                        new DataBuffer(DataBuffer.TYPE_BYTE, size * bands) {
+                            final int[] MASKS = {
+                                    0xffffff00,
+                                    0xffff00ff,
+                                    0xff00ffff,
+                                    0x00ffffff,
+                            };
+
+                            @Override
+                            public int getElem(int bank, int i) {
+                                int index = i / bands;
+                                int shift = (i % bands) * 8;
+
+                                return (buffer.getElem(index) >>> shift) & 0xff;
+                            }
+
+                            @Override
+                            public void setElem(int bank, int i, int val) {
+                                int index = i / bands;
+                                int element = i % bands;
+                                int shift = element * 8;
+
+                                int value = (buffer.getElem(index) & MASKS[element]) | ((val & 0xff) << shift);
+                                buffer.setElem(index, value);
+                            }
+                        }, new Point()) {
+                };
+
+            default:
+                throw new IllegalArgumentException(String.format("Raster type %d not supported", raster.getTransferType()));
+        }
+    }
+
+    private static int[] createBandOffsets(final SinglePixelPackedSampleModel sampleModel) {
+        notNull(sampleModel, "sampleModel");
+
+        int[] masks = sampleModel.getBitMasks();
+        int[] offs = new int[masks.length];
+
+        for (int i = 0; i < masks.length; i++) {
+            int mask = masks[i];
+            int off = 0;
+
+            // TODO: FixMe! This only works for standard 8 bit masks (0xFF)
+            if (mask != 0) {
+                while ((mask & 0xFF) == 0) {
+                    mask >>>= 8;
+                    off++;
+                }
+            }
+
+            offs[i] = off;
+        }
+
+        return offs;
+    }
+}