Question

我正在尝试使用透明而不是白色背景的Java显示中的图像创建png。尝试在新颜色（0,0,0,0）中将alpha设置为0 - 背景仍然显示为白色？

我正在使用BufferedImage

            WritableRaster raster = onscreenImage.getRaster();
            WritableRaster newRaster;
            newRaster = raster.createWritableChild(0, 0, width, height, 0, 0, new int[] {0, 1, 2});
            DirectColorModel cm = (DirectColorModel) onscreenImage.getColorModel();
            DirectColorModel newCM = new DirectColorModel(cm.getPixelSize(),
                                                          cm.getRedMask(),
                                                          cm.getGreenMask(),
                                                          cm.getBlueMask());
            BufferedImage rgbBuffer = new BufferedImage(newCM, newRaster, false,  null);
            try { ImageIO.write(rgbBuffer, suffix, file); }
            catch (IOException e) { e.printStackTrace(); }

Answer 1

您没有在颜色模型中指定alpha分量。试试这种方式：

newRaster = raster.createWritableChild(0, 0, width, height, 0, 0, null);
DirectColorModel cm = (DirectColorModel) onscreenImage.getColorModel();
DirectColorModel newCM = new DirectColorModel(cm.getPixelSize(),
                                                      cm.getRedMask(),
                                                      cm.getGreenMask(),
                                                      cm.getBlueMask(),
                                                      cm.getAlphaMask());

透明背景png - Java - BufferedImage

1 个答案: