php image manipulation

        $palette = imagecreatefrompng(public_path() . "/assets/palette.png");
        $metalsPalette = imagecreatefrompng(public_path() . "/assets/metalsPalette.png");
        $colorsPalette = imagecreatefrompng(public_path() . "/assets/colorsPalette.png");
        $basesPalette = imagecreatefrompng(public_path() . "/assets/basesPalette.png");
        $original1 = imagecreatefrompng(public_path() . '/uploads/test1.png');
        $original2 = imagecreatefrompng(public_path() . '/uploads/test2.png');
        $resampled1 = imagecreatetruecolor(5, 5);
        $resampled2 = imagecreatetruecolor(5, 5);
        $adjusted1 = imagecreatetruecolor(5, 5);
        $adjusted2 = imagecreatetruecolor(5, 5);
        $difference = imagecreatetruecolor(5, 5);
        $significantDifference = imagecreatetruecolor(5, 5);
        imagetruecolortopalette($palette, false, 16);
        imagetruecolortopalette($metalsPalette, false, 3);
        imagetruecolortopalette($colorsPalette, false, 6);
        imagetruecolortopalette($basesPalette, false, 6);

        imagecopyresampled($resampled1, $original1, 0, 0, 0, 0, 5, 5, imagesx($original1), imagesy($original1));
        imagecopyresampled($resampled2, $original2, 0, 0, 0, 0, 5, 5, imagesx($original2), imagesy($original2));

        $differenceCount = 0;
        $significantDifferenceCount = 0;
        for ($row = 0; $row < 5; $row++) {
            for ($column = 0; $column < 5; $column++) {
                $rgb1 = imagecolorat($resampled1, $column, $row);
                $rgb2 = imagecolorat($resampled2, $column, $row);
                $color1 = imagecolorsforindex($resampled1, $rgb1);
                $color2 = imagecolorsforindex($resampled2, $rgb2);
                $closestRgb1 = imagecolorclosest($palette, $color1['red'], $color1['green'], $color1['blue']);
                $closestRgb2 = imagecolorclosest($palette, $color2['red'], $color2['green'], $color2['blue']);
                $closestColor1 = imagecolorsforindex($palette, $closestRgb1);
                $closestColor2 = imagecolorsforindex($palette, $closestRgb2);
                imagesetpixel($adjusted1, $column, $row, imagecolorallocate($adjusted1, $closestColor1['red'], $closestColor1['green'], $closestColor1['blue']));
                imagesetpixel($adjusted2, $column, $row, imagecolorallocate($adjusted2, $closestColor2['red'], $closestColor2['green'], $closestColor2['blue']));
                if (imagecolorat($adjusted1, $column, $row) != imagecolorat($adjusted2, $column, $row)) {
                    imagesetpixel($difference, $column, $row, imagecolorallocate($difference, 255, 0, 0));
                    $differenceCount++;
                }
                if ((imagecolorexact($basesPalette, $closestColor1['red'], $closestColor1['green'], $closestColor1['blue']) > -1) &&
                    (imagecolorexact($basesPalette, $closestColor2['red'], $closestColor2['green'], $closestColor2['blue']) > -1)) {
                    // no significant difference
                } elseif ((imagecolorexact($colorsPalette, $closestColor1['red'], $closestColor1['green'], $closestColor1['blue']) > -1) &&
                    (imagecolorexact($colorsPalette, $closestColor2['red'], $closestColor2['green'], $closestColor2['blue']) > -1)) {
                    // no significant difference
                } elseif ((imagecolorexact($metalsPalette, $closestColor1['red'], $closestColor1['green'], $closestColor1['blue']) > -1) &&
                    (imagecolorexact($metalsPalette, $closestColor2['red'], $closestColor2['green'], $closestColor2['blue']) > -1)) {
                    // no significant difference
                } else {
                    imagesetpixel($significantDifference, $column, $row, imagecolorallocate($significantDifference, 255, 0, 0));
                    $significantDifferenceCount++;
                }
            }
        }