从值数组写入图像后，图像中的rgb像素值发生了变化

Question

Hi my code is like this

BufferedImage img1=new BufferedImage(w,h,BufferedImage.TYPE_INT_RGB);
for(int r=0; r<w; r++)
{
    for(int c=0; c<h; c++)
    {
        img1.setRGB(0, 0, w, h, data,0,w);
     }
}
ImageIO.write(img1,"jpg", new File("abc.jpg"));

I want to create image of width w and height h..I am having my pixel values in an int array called data(consists of combined rgb values)..ImageIO.write method creates the image but with different pixel values..please help me out..i tried very hardly..but still not getting..

Answer 1

The reason why is because you're using JPEG compression. JPEG compression is a lossy compression algorithm, so what you have stored in memory will not be the same as you have written to file. Lossy compression allows for high compression ratios, and to mimic or closely resemble what you visually see in the image, but the actual contents will not be the same. They will certainly be similar though.

The only way you can write to an image file and keep the image pixels the same is to use a lossless compression algorithm. Try using PNG instead.