This article mainly introduces the PHP image watermarking function. Interested friends can refer to it. I hope it will be helpful to everyone.
The example code is as follows:
<?php /** * 功能:给一张图片加上水印效果 * $i 要加水印效果的图片 * $t 水印文字 * $size 文字大小 * $pos 水印的位置 * $color 文字的颜色 * $flag 是布尔值,主要用来区分是不是原图上加水印 * $type 如果$flag等于false 则新图上加上水印 新文件名为 原名_txt.jpg */ function txt($i,$t='版权所有',$size=25,$pos=5,$color='rand',$flag=true,$type='_txt'){ $img = imagecreatefromjpeg($i); $w = imagesx($img); $h = imagesy($img); $font = dirname(__FILE__).'/font/ls.ttf'; $ps = imagettfbbox($size,0,$font,$t); $tw = $ps[4]; $th = abs($ps[5]); switch($pos){ case 1:break; case 2:break; case 3:break; case 4:break; case 5:$x=($w-$tw)/2;$y=($h-$th)/2+$th;break; case 6:break; case 7:break; case 8:break; case 9:break; default:break; } $c = getcolor($img,$color); imagettftext($img,$size,0,$x,$y,$c,$font,$t); if($flag){ imagejpeg($img,$i); }else{ $ext = ext($i); $ppp = rtrim($i,'.'.$ext); $ppp = $ppp.$type.'.'.$ext; imagejpeg($img,$ppp); } } function getcolor($i,$c='rand',$a=50){ $cc = ''; switch($c){ case 'white':$cc=imagecolorallocatealpha($i,255,255,255,$a);break; case 'black':$cc=imagecolorallocatealpha($i,0,0,0,$a);break; case 'red':$cc=imagecolorallocatealpha($i,255,0,0,$a);break; case 'green':$cc=imagecolorallocatealpha($i,0,255,0,$a);break; case 'blue':$cc=imagecolorallocatealpha($i,0,0,255,$a);break; case 'orange':$cc=imagecolorallocatealpha($i,0xff,0x66,0x33,$a);break; case 'yellow':$cc=imagecolorallocatealpha($i,255,255,0,$a);break; case 'rand':$cc=imagecolorallocatealpha($i,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255),$a);break; default: $cs = substr($c,1); $ok = str_split($cs,2); $cc = imagecolorallocatealpha($i,hexdec($ok[0]),hexdec($ok[1]),hexdec($ok[2]),$a); break; } return $cc; } /** * 功能是:返回扩展名 */ function ext($f){ $exts = explode('.',$f); return end($exts); } /** * 功能是:返回文件名,不含扩展名 */ function name($f){ $s = explode('/',$f); $fn = end($s); return rtrim($fn,'.'.ext($f)); }
Let’s look at another one that supports adding watermarks to pictures in two ways: pictures and text. Pictures support three formats: GIF, PNG, and JPG. Watermark pictures support PNG and GIF
function setWater($imgSrc,$markImg,$markText,$TextColor,$markPos,$fontType,$markType) { $srcInfo = @getimagesize($imgSrc); $srcImg_w = $srcInfo[0]; $srcImg_h = $srcInfo[1]; switch ($srcInfo[2]) { case 1: $srcim =imagecreatefromgif($imgSrc); break; case 2: $srcim =imagecreatefromjpeg($imgSrc); break; case 3: $srcim =imagecreatefrompng($imgSrc); break; default: die("不支持的图片文件类型"); exit; } if(!strcmp($markType,"img")) { if(!file_exists($markImg) || empty($markImg)) { return; } $markImgInfo = @getimagesize($markImg); $markImg_w = $markImgInfo[0]; $markImg_h = $markImgInfo[1]; if($srcImg_w < $markImg_w || $srcImg_h < $markImg_h) { return; } switch ($markImgInfo[2]) { case 1: $markim =imagecreatefromgif($markImg); break; case 2: $markim =imagecreatefromjpeg($markImg); break; case 3: $markim =imagecreatefrompng($markImg); break; default: die("不支持的水印图片文件类型"); exit; } $logow = $markImg_w; $logoh = $markImg_h; } if(!strcmp($markType,"text")) { $fontSize = 16; if(!empty($markText)) { if(!file_exists($fontType)) { return; } } else { return; } $box = @imagettfbbox($fontSize, 0, $fontType,$markText); $logow = max($box[2], $box[4]) - min($box[0], $box[6]); $logoh = max($box[1], $box[3]) - min($box[5], $box[7]); } if($markPos == 0) { $markPos = rand(1, 9); } switch($markPos) { case 1: $x = +5; $y = +5; break; case 2: $x = ($srcImg_w - $logow) / 2; $y = +5; break; case 3: $x = $srcImg_w - $logow - 5; $y = +15; break; case 4: $x = +5; $y = ($srcImg_h - $logoh) / 2; break; case 5: $x = ($srcImg_w - $logow) / 2; $y = ($srcImg_h - $logoh) / 2; break; case 6: $x = $srcImg_w - $logow - 5; $y = ($srcImg_h - $logoh) / 2; break; case 7: $x = +5; $y = $srcImg_h - $logoh - 5; break; case 8: $x = ($srcImg_w - $logow) / 2; $y = $srcImg_h - $logoh - 5; break; case 9: $x = $srcImg_w - $logow - 5; $y = $srcImg_h - $logoh -5; break; default: die("此位置不支持"); exit; } $dst_img = @imagecreatetruecolor($srcImg_w, $srcImg_h); imagecopy ( $dst_img, $srcim, 0, 0, 0, 0, $srcImg_w, $srcImg_h); if(!strcmp($markType,"img")) { imagecopy($dst_img, $markim, $x, $y, 0, 0, $logow, $logoh); imagedestroy($markim); } if(!strcmp($markType,"text")) { $rgb = explode(',', $TextColor); $color = imagecolorallocate($dst_img, $rgb[0], $rgb[1], $rgb[2]); imagettftext($dst_img, $fontSize, 0, $x, $y, $color, $fontType,$markText); } switch ($srcInfo[2]) { case 1: imagegif($dst_img, $imgSrc); break; case 2: imagejpeg($dst_img, $imgSrc); break; case 3: imagepng($dst_img, $imgSrc); break; default: die("不支持的水印图片文件类型"); exit; } imagedestroy($dst_img); imagedestroy($srcim); }
Summary: The above is the entire content of this article, I hope it can help Everyone’s learning helps.
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The above is the detailed content of PHP image watermark function. For more information, please follow other related articles on the PHP Chinese website!

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