Java实现多张图片合并一张，这个还是挺常用到的。
public class ImageUtil { public static boolean merge(String[] imgs, String type, String mergePic) { int dstHeight = 0; int dstWidth = 0; // 获取需要拼接的图片长度 int len = imgs.length; // 判断长度是否大于0 if (len < 1) { return false; } File[] file = new File[len]; BufferedImage[] images = new BufferedImage[len]; int[][] ImageArrays = new int[len][]; for (int i = 0; i < len; i++) { try { file[i] = new File(imgs[i]); images[i] = ImageIO.read(file[i]); } catch (Exception e) { e.printStackTrace(); return false; } int width = images[i].getWidth(); int height = images[i].getHeight(); // 从图片中读取RGB 像素 ImageArrays[i] = new int[width * height]; ImageArrays[i] = images[i].getRGB(0, 0, width, height, ImageArrays[i], 0, width); // 计算合并的宽度和高度 dstWidth = dstWidth > width ? dstWidth : width; dstHeight += height; } // 合成图片像素 System.out.println("宽度:" + dstWidth); System.out.println("高度:" + dstHeight); if (dstHeight < 1) { System.out.println("dstHeight < 1"); return false; } // 生成新图片 try { BufferedImage imageNew = new BufferedImage(dstWidth, dstHeight, BufferedImage.TYPE_INT_RGB); int width_i = 0; int height_i = 0; for (int i = 0; i < images.length; i++) { int width = images[i].getWidth(); int height = images[i].getHeight(); imageNew.setRGB(0, height_i, width, height, ImageArrays[i], 0, width); height_i += height; } File outFile = new File(mergePic); // 写图片，输出到硬盘 ImageIO.write(imageNew, type, outFile); } catch (Exception e) { e.printStackTrace(); return false; } return true; } public static void main(String[] args) throws Exception { String saveFile = "E:\tmp\avatar2.png"; String images[] = {"E:\tmp\avatar.png", "E:\tmp\avatar.png"}; ImageUtil.merge(images, "png", saveFile); }}效果如下：