求教:读入一幅gif图片,如何把其中5种颜色替换成透明?
class MyImage{ static function ImageColorAllocateHEX($im, $s){ if($s{0} == "#") $s = substr($s,1); $bg_dec = hexdec($s); return imagecolorallocate($im, ($bg_dec & 0xFF0000) >> 16, ($bg_dec & 0x00FF00) >> 8, ($bg_dec & 0x0000FF) ); } static function imagetextouter(&$im, $size, $x, $y, $color, $fontfile, $text, $outer){ $ttf = false; if (is_file($fontfile)){ $ttf = true; $area = imagettfbbox($size, 0, $fontfile, $text); $width = $area[2] - $area[0] + 2; $height = $area[1] - $area[5] + 2; } else { $width = strlen($text) * 10; $height = 16; } $im_tmp = imagecreate($width, $height); $white = imagecolorallocate($im_tmp, 255, 255, 255); $black = imagecolorallocate($im_tmp, 0, 0, 0); $color = self::ImageColorAllocateHEX($im, $color); $outer = self::ImageColorAllocateHEX($im, $outer); if ($ttf){ imagettftext($im_tmp, $size, 0, 0, $height - 2, $black, $fontfile, $text); imagettftext($im, $size, 0, $x, $y, $color, $fontfile, $text); $y = $y - $height + 2; } else{ imagestring($im_tmp, $size, 0, 0, $text, $black); imagestring($im, $size, $x, $y, $text, $color); } for ($i = 0; $i < $width; $i ++){ for ($j = 0; $j < $height; $j ++){ $c = ImageColorAt($im_tmp, $i, $j); if ($c !== $white){ ImageColorAt ($im_tmp, $i, $j - 1) != $white || imagesetpixel($im, $x + $i, $y + $j - 1, $outer); ImageColorAt ($im_tmp, $i, $j + 1) != $white || imagesetpixel($im, $x + $i, $y + $j + 1, $outer); ImageColorAt ($im_tmp, $i - 1, $j) != $white || imagesetpixel($im, $x + $i - 1, $y + $j, $outer); ImageColorAt ($im_tmp, $i + 1, $j) != $white || imagesetpixel($im, $x + $i + 1, $y + $j, $outer); // 取消注释,与Fireworks的发光效果相同 ImageColorAt ($im_tmp, $i - 1, $j - 1) != $white || imagesetpixel($im, $x + $i - 1, $y + $j - 1, $outer); ImageColorAt ($im_tmp, $i + 1, $j - 1) != $white || imagesetpixel($im, $x + $i + 1, $y + $j - 1, $outer); ImageColorAt ($im_tmp, $i - 1, $j + 1) != $white || imagesetpixel($im, $x + $i - 1, $y + $j + 1, $outer); ImageColorAt ($im_tmp, $i + 1, $j + 1) != $white || imagesetpixel($im, $x + $i + 1, $y + $j + 1, $outer); } } } imagedestroy($im_tmp); } }
你要的东西在这个例子里可以找到思路,具体的自己动下手呗,呵呵
昵称: asmodai 时间: 2013-05-28 15:36:06
1、rgb=4,2,4
2、rgb=252,230,180
3、rgb=252,254,252
4、rgb=252,162,124
5、rgb=124,254,212
真心求教,谢谢高手!