diference between stb_loadimage() and raster.getPixels() of java for same file

i wrote two codes to get image data. one from java and one from c++;

C++ code:

unsigned char *data1 = stbi_load("C:/Users/skss/Pictures/Untitled.png", &width1, &height1, &nrChannels1, 0);

And for java:

BufferedImage img=ImageIO.read(new File    ("C:/Users/skss/Pictures/Untitled.png"));
Raster ras=img.getRaster();
double[] data=new double[img.getWidth()*img.getHeight()*3];
ras.getPixels(0,0,img.getWidth(),img.getHeight(),data);

but these two not producing same results