public boolean getPerformGammaCorrection() {
        return performGammaCorrection;
    }
Returns <code>true</code> if gamma correction is to be performed
on the image data.  The default is <code>true</code>.

<p> If gamma correction is to be performed, the
<code>getUserExponent()</code> and
<code>getDisplayExponent()</code> methods are used in addition to
the gamma value stored within the file (or the default value of
1/2.2 used if no value is found) to produce a single exponent
using the formula:
<pre>
decoding_exponent = user_exponent/(gamma_from_file * display_exponent)
</pre>
plugins/svg-plugin/batik-codec-fix/src/main/java/org/apache/batik/ext/awt/image/codec/png/PNGDecodeParam.java