ImgUtil的sliceByRowsAndCols背景无法透明问题

hutool-extra/src/main/java/org/dromara/hutool/extra/qrcode/QrDecoder.java

@@ -26,6 +26,7 @@ import com.google.zxing.common.GlobalHistogramBinarizer;
 import com.google.zxing.common.HybridBinarizer;
 
 import java.awt.Image;
+import java.awt.image.BufferedImage;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -74,7 +75,8 @@ public class QrDecoder implements Decoder<Image, String> {
 		final MultiFormatReader formatReader = new MultiFormatReader();
 		formatReader.setHints(hints);
 
-		final LuminanceSource source = new BufferedImageLuminanceSource(ImgUtil.toBufferedImage(image));
+		final LuminanceSource source = new BufferedImageLuminanceSource(
+			ImgUtil.castToBufferedImage(image, ImgUtil.IMAGE_TYPE_JPG));
 
 		Result result = _decode(formatReader, new HybridBinarizer(source));
 		if (null == result) {

hutool-swing/src/main/java/org/dromara/hutool/swing/img/Img.java

@@ -135,7 +135,7 @@ public class Img implements Serializable {
 	 * @return Img
 	 */
 	public static Img from(final Image image) {
-		return new Img(ImgUtil.toBufferedImage(image));
+		return new Img(ImgUtil.castToBufferedImage(image, ImgUtil.IMAGE_TYPE_JPG));
 	}
 
 	/**
@@ -368,7 +368,8 @@ public class Img implements Serializable {
 		final Image srcImage = getValidSrcImg();
 		fixRectangle(rectangle, srcImage.getWidth(null), srcImage.getHeight(null));
 
-		final ImageFilter cropFilter = new CropImageFilter(rectangle.x, rectangle.y, rectangle.width, rectangle.height);
+		final ImageFilter cropFilter = new CropImageFilter(
+			rectangle.x, rectangle.y, rectangle.width, rectangle.height);
 		this.targetImage = ImgUtil.filter(cropFilter, srcImage);
 		return this;
 	}
@@ -685,8 +686,8 @@ public class Img implements Serializable {
 	 */
 	public Img stroke(final Color color, final Stroke stroke) {
 		final BufferedImage image = ImgUtil.toBufferedImage(getValidSrcImg(), this.targetImageType);
-		final int width = image.getWidth(null);
+		final int width = image.getWidth();
-		final int height = image.getHeight(null);
+		final int height = image.getHeight();
 		final Graphics2D g = image.createGraphics();
 
 		g.setColor(ObjUtil.defaultIfNull(color, Color.BLACK));

hutool-swing/src/main/java/org/dromara/hutool/swing/img/ImgUtil.java

@@ -445,17 +445,13 @@ public class ImgUtil {
 	 * 图像切割（指定切片的行数和列数）
 	 *
 	 * @param srcImageFile 源图像文件
-	 * @param destDir      切片目标文件夹
+	 * @param targetDir      切片目标文件夹
 	 * @param formatName   格式名称，即图片格式后缀
 	 * @param rows         目标切片行数。默认2，必须是范围 [1, 20] 之内
 	 * @param cols         目标切片列数。默认2，必须是范围 [1, 20] 之内
 	 */
-	public static void sliceByRowsAndCols(final File srcImageFile, final File destDir, final String formatName, final int rows, final int cols) {
+	public static void sliceByRowsAndCols(final File srcImageFile, final File targetDir, final String formatName, final int rows, final int cols) {
-		try {
+		sliceByRowsAndCols(read(srcImageFile), targetDir, formatName, rows, cols);
-			sliceByRowsAndCols(ImageIO.read(srcImageFile), destDir, formatName, rows, cols);
-		} catch (final IOException e) {
-			throw new IORuntimeException(e);
-		}
 	}
 
 	/**
@@ -474,7 +470,6 @@ public class ImgUtil {
 			throw new IllegalArgumentException("Destination must be a Directory !");
 		}
 
-		try {
 		if (rows <= 0 || rows > 20) {
 			rows = 2; // 切片行数
 		}
@@ -482,25 +477,21 @@ public class ImgUtil {
 			cols = 2; // 切片列数
 		}
 		// 读取源图像
-			final BufferedImage bi = toBufferedImage(srcImage);
+		final int srcWidth = srcImage.getWidth(null); // 源图宽度
-			final int srcWidth = bi.getWidth(); // 源图宽度
+		final int srcHeight = srcImage.getHeight(null); // 源图高度
-			final int srcHeight = bi.getHeight(); // 源图高度
 
-			final int destWidth = NumberUtil.partValue(srcWidth, cols); // 每张切片的宽度
+		final int targetWidth = NumberUtil.partValue(srcWidth, cols); // 每张切片的宽度
-			final int destHeight = NumberUtil.partValue(srcHeight, rows); // 每张切片的高度
+		final int targetHeight = NumberUtil.partValue(srcHeight, rows); // 每张切片的高度
 
 		// 循环建立切片
 		Image tag;
 		for (int i = 0; i < rows; i++) {
 			for (int j = 0; j < cols; j++) {
-					tag = cut(bi, new Rectangle(j * destWidth, i * destHeight, destWidth, destHeight));
+				tag = cut(srcImage, new Rectangle(j * targetWidth, i * targetHeight, targetWidth, targetHeight));
 				// 输出为文件
-					ImageIO.write(toRenderedImage(tag), formatName, new File(destDir, "_r" + i + "_c" + j + ".jpg"));
+				write(tag, new File(destDir, "_r" + i + "_c" + j + "." +  formatName));
 			}
 		}
-		} catch (final IOException e) {
-			throw new IORuntimeException(e);
-		}
 	}
 	// endregion
 
@@ -558,8 +549,9 @@ public class ImgUtil {
 	 * @since 4.1.14
 	 */
 	public static void convert(final Image srcImage, final String formatName, final ImageOutputStream destImageStream, final boolean isSrcPng) {
+		final BufferedImage src = toBufferedImage(srcImage, isSrcPng ? BufferedImage.TYPE_INT_ARGB : BufferedImage.TYPE_INT_RGB);
 		try {
-			ImageIO.write(isSrcPng ? copyImage(srcImage, BufferedImage.TYPE_INT_RGB) : toBufferedImage(srcImage), formatName, destImageStream);
+			ImageIO.write(src, formatName, destImageStream);
 		} catch (final IOException e) {
 			throw new IORuntimeException(e);
 		}
@@ -1148,30 +1140,32 @@ public class ImgUtil {
 	 * 首先尝试强转，否则新建一个{@link BufferedImage}后重新绘制，使用 {@link BufferedImage#TYPE_INT_RGB} 模式。
 	 *
 	 * @param img {@link Image}
+	 * @param imageType 目标图片类型，例如jpg或png等
 	 * @return {@link BufferedImage}
 	 * @since 4.3.2
 	 */
-	public static RenderedImage toRenderedImage(final Image img) {
+	public static RenderedImage castToRenderedImage(final Image img, final String imageType) {
 		if (img instanceof RenderedImage) {
 			return (RenderedImage) img;
 		}
 
-		return copyImage(img, BufferedImage.TYPE_INT_RGB);
+		return toBufferedImage(img, imageType);
 	}
 
 	/**
 	 * {@link Image} 转 {@link BufferedImage}<br>
-	 * 首先尝试强转，否则新建一个{@link BufferedImage}后重新绘制，使用 {@link BufferedImage#TYPE_INT_RGB} 模式
+	 * 首先尝试强转，否则新建一个{@link BufferedImage}后重新绘制，使用 imageType 模式
 	 *
 	 * @param img {@link Image}
+	 * @param imageType 目标图片类型，例如jpg或png等
 	 * @return {@link BufferedImage}
 	 */
-	public static BufferedImage toBufferedImage(final Image img) {
+	public static BufferedImage castToBufferedImage(final Image img, final String imageType) {
 		if (img instanceof BufferedImage) {
 			return (BufferedImage) img;
 		}
 
-		return copyImage(img, BufferedImage.TYPE_INT_RGB);
+		return toBufferedImage(img, imageType);
 	}
 
 	/**

hutool-swing/src/main/java/org/dromara/hutool/swing/img/ImgWriter.java

@@ -69,7 +69,7 @@ public class ImgWriter {
 	 * @param imageType 图片类型（图片扩展名），{@code null}表示使用RGB模式（JPG）
 	 */
 	public ImgWriter(final Image image, final String imageType) {
-		this.image = ImgUtil.toRenderedImage(image);
+		this.image = ImgUtil.castToRenderedImage(image, imageType);
 		this.writer = ImgUtil.getWriter(image, imageType);
 	}
 

hutool-swing/src/test/java/org/dromara/hutool/swing/img/ImgUtilTest.java

@@ -62,7 +62,9 @@ public class ImgUtilTest {
 	@Test
 	@Disabled
 	public void cutTest() {
-		ImgUtil.cut(FileUtil.file("d:/face.jpg"), FileUtil.file("d:/face_result.jpg"), new Rectangle(200, 200, 100, 100));
+		ImgUtil.cut(FileUtil.file("d:/test/hutool.png"),
+			FileUtil.file("d:/test/result.png"),
+			new Rectangle(0, 0, 400, 240));
 	}
 
 	@Test
@@ -106,6 +108,14 @@ public class ImgUtilTest {
 		ImgUtil.sliceByRowsAndCols(FileUtil.file("d:/test/logo.jpg"), FileUtil.file("d:/test/dest"), ImgUtil.IMAGE_TYPE_JPEG, 1, 5);
 	}
 
+	@Test
+	@Disabled
+	public void sliceByRowsAndColsTest2() {
+		ImgUtil.sliceByRowsAndCols(
+			FileUtil.file("d:/test/hutool.png"),
+			FileUtil.file("d:/test/dest"), ImgUtil.IMAGE_TYPE_PNG, 1, 5);
+	}
+
 	@Test
 	@Disabled
 	public void convertTest() {