+ unsigned char * bits = new unsigned char [imagebitcount];
+ unsigned char * maskBits = new unsigned char [imagebitcount];
+
+ int i, j, i8; unsigned char c, cMask;
+ for (i=0; i<imagebitcount; i++)
+ {
+ bits[i] = 0;
+ i8 = i * 8;
+
+ cMask = 1;
+ for (j=0; j<8; j++)
+ {
+ // possible overflow if we do the summation first ?
+ c = rgbBits[(i8+j)*3]/3 + rgbBits[(i8+j)*3+1]/3 + rgbBits[(i8+j)*3+2]/3;
+ //if average value is > mid grey
+ if (c>127)
+ bits[i] = bits[i] | cMask;
+ cMask = cMask * 2;
+ }
+ }
+
+ unsigned long keyMaskColor;
+ if (bHasMask)
+ {
+ unsigned char
+ r = image.GetMaskRed(),
+ g = image.GetMaskGreen(),
+ b = image.GetMaskBlue();
+
+ for (i=0; i<imagebitcount; i++)
+ {
+ maskBits[i] = 0x0;
+ i8 = i * 8;
+
+ cMask = 1;
+ for (j=0; j<8; j++)
+ {
+ if (rgbBits[(i8+j)*3] != r || rgbBits[(i8+j)*3+1] != g || rgbBits[(i8+j)*3+2] != b)
+ maskBits[i] = maskBits[i] | cMask;
+ cMask = cMask * 2;
+ }
+ }
+
+ keyMaskColor = (r << 16) | (g << 8) | b;
+ }
+ else // no mask
+ {
+ for (i=0; i<imagebitcount; i++)
+ maskBits[i] = 0xFF;
+
+ // init it to avoid compiler warnings
+ keyMaskColor = 0;
+ }
+
+ // find the most frequent color(s)
+ wxImageHistogram histogram;
+ image.ComputeHistogram(histogram);
+
+ // colors as rrggbb
+ unsigned long key;
+ unsigned long value;
+
+ long colMostFreq = 0;
+ unsigned long nMost = 0;
+ long colNextMostFreq = 0;
+ unsigned long nNext = 0;
+ for ( wxImageHistogram::iterator entry = histogram.begin();
+ entry != histogram.end();
+ ++entry )
+ {
+ value = entry->second.value;
+ key = entry->first;
+ if ( !bHasMask || (key != keyMaskColor) )
+ {
+ if (value > nMost)
+ {
+ nMost = value;
+ colMostFreq = key;
+ }
+ else if (value > nNext)
+ {
+ nNext = value;
+ colNextMostFreq = key;
+ }
+ }
+ }