我有一个具有透明度的TYPE_4BYTE_ABGR imageType的BufferedImage,我想将其转换为TYPE_3BYTE_BGR BufferedImage.我试图在TYPE_3BYTE_BGR上绘制TYPE_4BYTE_ABGR图像,但它改变了颜色.

目的是将透明图像放在白色背景上,因为如果只是将TYPE_4BYTE_AGBR图像写入.jpg,他就会获得黑色透明区域.

解决方法:

这是您需要的代码,您必须在具有Alpha通道的新图像中使用100％alpha的相同颜色.

// bufferedImage is your image.
if (bufferedImage.getType() == BufferedImage.TYPE_3BYTE_BGR) {
    BufferedImage bff = new BufferedImage(bufferedImage.getWidth(), bufferedImage.getHeight(), BufferedImage.TYPE_4BYTE_ABGR);
    for (int y = 0; y < bufferedImage.getHeight(); ++y) {
        for (int x = 0; x < bufferedImage.getWidth(); ++x) {
        int argb = bufferedImage.getRGB(x, y);
        bff.setRGB(x, y, argb & 0xFF000000); // same color alpha 100%
        }
    }
    return bff;
} else {
    return bufferedImage;
}

如果你想在白色背景上放置透明图像,你应该使用不同类型的新BufferedImage.这样做的代码是这样的：

// bufferedImage is your image.
if (bufferedImage.getType() == BufferedImage.TYPE_4BYTE_ABGR) {
    for (int y = 0; y < bufferedImage.getHeight(); ++y) {
        for (int x = 0; x < bufferedImage.getWidth(); ++x) {
            int argb = bufferedImage.getRGB(x, y);
            if((argb & 0x00FFFFFF) == 0x00FFFFFF){ //if the pixel is transparent
                bufferedImage.setRGB(x, y, 0xFFFFFFFF); // white color.
            }
        }
    }
    return bufferedImage;
}