将JavaFX Image对象转换为字节数组

Question

我们可以使用创建FX Image对象

byte [] bytes = ------; //valid image in bytes
javafx.scene.image.Image image = new Image(new ByteArrayInputStream(bytes));

这可以设置为ImageView.

我需要相反而不首先将其转换为BufferedImage(SwingFXUtils.fromFXImage(image,null)).

这样我就可以直接将字节写入文件.

我尝试过以下方法:

PixelReader pixelReader = image.getPixelReader();
    int width = (int)image.getWidth();
    int height = (int)image.getHeight();
    byte[] buffer = new byte[width * height * 4];
    pixelReader.getPixels(
            0,
            0,
            width,
            height,
            PixelFormat.getByteBgraInstance(),
            buffer,
            0,
            width * 4
    );

但是通过写byte []缓冲区生成的文件不是有效图像.

有什么见解吗？

编辑:如何从javafx imageView获取byte []的解决方案不能应用于我的问题.正如我已经清楚地提到过,我不想使用SwingFXUtils将其转换为BufferedImage.此外,我想将其转换为字节数组,以便可以将其写入图像文件.

Answer 1

这是后来的,但如果有人想要找出来,试试这个:

// Load the Image into a Java FX Image Object //

Image img = new Image(new FileInputStream("SomeImageFile.png") );

// Cache Width and Height to 'int's (because getWidth/getHeight return Double) and getPixels needs 'int's //

int w = (int)img.getWidth();
int h = (int)img.getHeight();

// Create a new Byte Buffer, but we'll use BGRA (1 byte for each channel) //

byte[] buf = new byte[w * h * 4];

/* Since you can get the output in whatever format with a WritablePixelFormat,
   we'll use an already created one for ease-of-use. */

img.getPixelReader().getPixels(0, 0, w, h, PixelFormat.getByteBgraInstance(), buf, 0, w * 4);

/* Second last parameter is byte offset you want to start in your buffer,
   and the last parameter is stride (in bytes) per line for your buffer. */