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public BufferedImage EdgeW(BufferedImage bi)
{
BufferedImage buff = new BufferedImage(bi.getWidth(), bi.getHeight(), bi.getType());

Kernel kernel = new Kernel(3, 3, new float[] {
-1f, 0f, 1f,
-2f, 0f, 2f,
-1f, 0f, 1f
});

ConvolveOp op = new ConvolveOp(kernel);
op.filter(bi, buff);

return buff;
}

public BufferedImage EdgeH(BufferedImage bi)
{
BufferedImage buff = new BufferedImage(bi.getWidth(), bi.getHeight(), bi.getType());

Kernel kernel = new Kernel(3, 3, new float[] {
-1f, -2f, -1f,
0f,  0f,  0f,
1f,  2f,   1f
});

ConvolveOp op = new ConvolveOp(kernel);
op.filter(bi, buff);

return buff;
}

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