diff --git a/src/java.desktop/share/classes/com/sun/imageio/plugins/bmp/BMPImageWriter.java b/src/java.desktop/share/classes/com/sun/imageio/plugins/bmp/BMPImageWriter.java index ea47d9d35e6..962a47aa922 100644 --- a/src/java.desktop/share/classes/com/sun/imageio/plugins/bmp/BMPImageWriter.java +++ b/src/java.desktop/share/classes/com/sun/imageio/plugins/bmp/BMPImageWriter.java @@ -1,5 +1,5 @@ /* - * Copyright (c) 2003, 2023, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it @@ -1111,7 +1111,7 @@ public class BMPImageWriter extends ImageWriter implements BMPConstants { incCompImageSize(1); } // Padding to word align absolute encoding - if ( !isEven((int)Math.ceil((absVal-1)/2)) ) { + if (!isEven((absVal - 1) / 2)) { stream.writeByte(0); incCompImageSize(1); } @@ -1247,7 +1247,7 @@ public class BMPImageWriter extends ImageWriter implements BMPConstants { } // Padding - if ( !isEven((int)Math.ceil((absVal+1)/2)) ) { + if (!isEven((absVal + 2) / 2)) { stream.writeByte(0); incCompImageSize(1); } diff --git a/test/jdk/javax/imageio/plugins/bmp/RLE4PaddingTest.java b/test/jdk/javax/imageio/plugins/bmp/RLE4PaddingTest.java new file mode 100644 index 00000000000..e1e341fabe0 --- /dev/null +++ b/test/jdk/javax/imageio/plugins/bmp/RLE4PaddingTest.java @@ -0,0 +1,113 @@ +/* + * Copyright (c) 2026, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +/* + * @test + * @bug 8384512 + * @summary Test verifies that BMP images are encoded correctly with RLE4 + * compression and odd number of distinct pixels at the end of + * scanline. + */ + +import java.awt.image.BufferedImage; +import java.awt.image.IndexColorModel; +import java.io.ByteArrayInputStream; +import java.io.ByteArrayOutputStream; +import java.io.IOException; + +import javax.imageio.IIOImage; +import javax.imageio.ImageIO; +import javax.imageio.ImageWriteParam; +import javax.imageio.ImageWriter; +import javax.imageio.stream.ImageOutputStream; + +public class RLE4PaddingTest { + private static final int width = 5; + private static final int height = 2; + private static BufferedImage getTestImage() { + // create BufferedImage with width 5 and all distinct pixels, + // so that it uses absolute mode for RLE. + // If we don't add appropriate padding at end of the scanline, + // the encoded data of next scanline will be corrupt. + int bpp = 4; + int size = 16; + byte[] r = new byte[16]; + byte[] g = new byte[16]; + byte[] b = new byte[16]; + + for (int i = 0; i < 16; i++) { + r[i] = g[i] = b[i] = (byte)(i * 16); + } + IndexColorModel icm = new IndexColorModel(bpp, size, r, g, b); + BufferedImage src = new BufferedImage(width, height, + BufferedImage.TYPE_BYTE_INDEXED, icm); + + int[][] rows = { + {1, 2, 3, 4, 5}, + {6, 7, 8, 9, 10} + }; + + for (int y = 0; y < src.getHeight(); y++) { + for (int x = 0; x < src.getWidth(); x++) { + src.getRaster().setSample(x, y, 0, rows[y][x]); + } + } + return src; + } + + public static void main(String[] args) throws IOException { + BufferedImage src = getTestImage(); + + ByteArrayOutputStream baos = new ByteArrayOutputStream(); + ImageOutputStream ios = ImageIO.createImageOutputStream(baos); + ImageWriter writer = ImageIO.getImageWritersByFormatName("BMP").next(); + writer.setOutput(ios); + ImageWriteParam param = writer.getDefaultWriteParam(); + param.setCompressionMode(ImageWriteParam.MODE_EXPLICIT); + param.setCompressionType("BI_RLE4"); + writer.write(null, new IIOImage(src, null, null), param); + ios.close(); + baos.close(); + + ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray()); + BufferedImage dst = ImageIO.read(bais); + + checkResult(src, dst); + } + + private static void checkResult(BufferedImage src, BufferedImage dst) { + for (int x = 0; x < width; x++) { + for (int y = 0; y < height; y++) { + int srcRgb = src.getRGB(x, y); + int dstRgb = dst.getRGB(x, y); + + if (srcRgb != dstRgb) { + throw new RuntimeException("Test failed due to color" + + " difference: " + Integer.toHexString(dstRgb) + + " instead of " + Integer.toHexString(srcRgb) + + " at [" + x + ", " + y + "]"); + } + } + } + } +}