Convert jpeg/png to an array of pixels in java

Question

How can I convert a string containing a jpeg or png to an array (preferably one dimensional) of pixels? Ideally using classes built into java?

Answer 1

It turns out you need commons-fileupload. Look at the user guide for how to obtain the image InputStream. From there you can simply call:

BufferedImage image = ImageIO.read(item.getInputStream());

From here on there are many ways:

• loop over the image dimensions and for each x and y call int rgb = image.getRGB(x, y);
• same as above, but call getRed(x, y), getGreen(x, y), getBlue(x, y)
• get the ColorModel and call the above methods there
• call getRGB(startX, startY, w, h, rgbArray, offset, scansize)
• call getData(), which returns a Raster, and call getPixes(..) there

Answer 2

Use PixelGraber. It returns one-dimensional array of RGB data.