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?

Does this string contain the file name of a file, or the raw image data? — Anon.
– Anon., Commented Feb 3, 2010 at 21:53
whatever a POST HTTP file submission would be, I'm guessing base 64 encoded? — Matt
– Matt, Commented Feb 3, 2010 at 21:57

Bozho · Accepted Answer · 2010-02-04 07:13:26Z

6

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

answered Feb 3, 2010 at 22:05

Bozho

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Comments

Denis Tulskiy · Accepted Answer · 2010-02-03 23:48:29Z

0

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

answered Feb 3, 2010 at 23:48

Denis Tulskiy

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