ThinkPHP使用Imagick给图片加文字
Posted 益达915
tags:
篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了ThinkPHP使用Imagick给图片加文字相关的知识，希望对你有一定的参考价值。
在php处理文字的过程中，imagettftext是一个给图片添加水印的方式，可以动态指定字体、文字、大小，用起来比较方便；
在ThinkPHP中，可以方便地使用Imagick来完成相应的效果ImagickDraw.annotateImage,但是二者共同的问题是文字不能自动根据宽度换行；
解决的办法就是计算文字的宽度，利用imagettfbox计算文字宽度，并且重构字符串在一些地方加入\\n符号(http://php.net/manual/en/function.imagettfbbox.php#68518)
于是经过在网上的搜寻，整合出以下代码：
/** * 返回一个字符的数组 * * @param $str 文字 * @param $charset 字符编码 * @return $match 返回一个字符的数组 */ function charArray($str,$charset="utf-8"){ $re[\'utf-8\'] = "/[\\x01-\\x7f]|[\\xc2-\\xdf][\\x80-\\xbf]|[\\xe0-\\xef][\\x80-\\xbf]{2}|[\\xf0-\\xff][\\x80-\\xbf]{3}/"; $re[\'gb2312\'] = "/[\\x01-\\x7f]|[\\xb0-\\xf7][\\xa0-\\xfe]/"; $re[\'gbk\'] = "/[\\x01-\\x7f]|[\\x81-\\xfe][\\x40-\\xfe]/"; $re[\'big5\'] = "/[\\x01-\\x7f]|[\\x81-\\xfe]([\\x40-\\x7e]|\\xa1-\\xfe])/"; preg_match_all($re[$charset], $str, $match); return $match; } /** * 返回一个字符串在图片中所占的宽度 * @param $fontsize 字体大小 * @param $fontangle 角度 * @param $ttfpath 字体文件 * @param $char 字符 * @return $width */ function charwidth($fontsize,$fontangle,$ttfpath,$char){ $box = imagettfbbox($fontsize,$fontangle,$ttfpath,$char); $width = max($box[2], $box[4]) - min($box[0], $box[6]); return $width; } /** * 根据预设宽度让文字自动换行 * @param $fontsize 字体大小 * @param $ttfpath 字体名称 * @param $str 字符串 * @param $width 预设宽度 * @param $fontangle 角度 * @param $charset 编码 * @return $_string 字符串 */ function autowrap($fontsize,$ttfpath,$str,$width,$fontangle=0,$charset=\'utf-8\'){ $_string = ""; $_width = 0; $temp = $this->chararray($str); foreach ($temp[0] as $v){ $w = $this->charwidth($fontsize,$fontangle,$ttfpath,$v); $_width += intval($w); if (($_width > $width) && ($v !== "")){ $_string .= PHP_EOL; $_width = 0; } $_string .= $v; } return $_string; }
我使用的是ThinkPHP，所以会有一些特殊的已经定义过的符号；
NOTE！！！
非常重要的一点，PHP里使用的文字单位不是像素，而是磅，所以会造成位置的偏差；
这个问题还没有找到好的解决办法，网上似乎也有二者的转换方法，但是需要结合图片分辨率吧，我记得我用了效果也不是很好；
/** * 实现php后台里，指定文字大小时，单位转换 * @param $px * @return int */ function px2dp($px){ $map=array( 0,4, 5, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 21, 22, 23, 25, 26, 27, 28, 29, 30, 32, 33, 34, 35, 36, 38, 39, 40, 41, 43, 44, 46, 47, 48, 48, 50, 51); //遍历数组 for($i=1;$i<count($map);$i++){ //恰好有匹配的磅值 if($map[$i]==$px){ return $i; } //如果当前像素值恰好在两个磅值之间 if($map[$i]<$px && $map[$i+1]>$px){ return $i+0.5; } } } //附录-->磅转像素表 /* * 1磅==>4像素, PPI=288 2磅==>5像素, PPI=180 3磅==>7像素, PPI=168 4磅==>8像素, PPI=144 5磅==>9像素, PPI=129.6 6磅==>10像素, PPI=120 7磅==>11像素, PPI=113.14285714286 8磅==>12像素, PPI=108 9磅==>14像素, PPI=112 10磅==>15像素, PPI=108 11磅==>16像素, PPI=104.72727272727 12磅==>17像素, PPI=102 13磅==>18像素, PPI=99.692307692308 14磅==>19像素, PPI=97.714285714286 15磅==>21像素, PPI=100.8 16磅==>22像素, PPI=99 17磅==>23像素, PPI=97.411764705882 18磅==>25像素, PPI=100 19磅==>26像素, PPI=98.526315789474 20磅==>27像素, PPI=97.2 21磅==>28像素, PPI=96 22磅==>29像素, PPI=94.909090909091 23磅==>30像素, PPI=93.913043478261 24磅==>32像素, PPI=96 25磅==>33像素, PPI=95.04 26磅==>34像素, PPI=94.153846153846 27磅==>35像素, PPI=93.333333333333 28磅==>36像素, PPI=92.571428571429 29磅==>38像素, PPI=94.344827586207 30磅==>39像素, PPI=93.6 31磅==>40像素, PPI=92.903225806452 32磅==>41像素, PPI=92.25 33磅==>43像素, PPI=93.818181818182 34磅==>44像素, PPI=93.176470588235 35磅==>46像素, PPI=94.628571428571 36磅==>47像素, PPI=94 37磅==>48像素, PPI=93.405405405405 38磅==>48像素, PPI=90.947368421053 39磅==>50像素, PPI=92.307692307692 40磅==>51像素, PPI=91.8 41磅==>52像素, PPI=91.317073170732 42磅==>53像素, PPI=90.857142857143 43磅==>55像素, PPI=92.093023255814 44磅==>56像素, PPI=91.636363636364 45磅==>57像素, PPI=91.2 46磅==>58像素, PPI=90.782608695652 47磅==>60像素, PPI=91.914893617021 48磅==>62像素, PPI=93 49磅==>63像素, PPI=92.571428571429 50磅==>63像素, PPI=90.72 51磅==>64像素, PPI=90.352941176471 52磅==>67像素, PPI=92.769230769231 53磅==>68像素, PPI=92.377358490566 54磅==>69像素, PPI=92 55磅==>70像素, PPI=91.636363636364 56磅==>71像素, PPI=91.285714285714 57磅==>72像素, PPI=90.947368421053 58磅==>74像素, PPI=91.862068965517 59磅==>75像素, PPI=91.525423728814 60磅==>76像素, PPI=91.2 61磅==>77像素, PPI=90.885245901639 62磅==>78像素, PPI=90.58064516129 63磅==>79像素, PPI=90.285714285714 64磅==>81像素, PPI=91.125 65磅==>83像素, PPI=91.938461538462 66磅==>84像素, PPI=91.636363636364 67磅==>85像素, PPI=91.34328358209 68磅==>86像素, PPI=91.058823529412 69磅==>86像素, PPI=89.739130434783 70磅==>88像素, PPI=90.514285714286 71磅==>90像素, PPI=91.267605633803 72磅==>91像素, PPI=91 73磅==>92像素, PPI=90.739726027397 74磅==>93像素, PPI=90.486486486486 * */
并且我在项目中使用的是Imagick方式生成图片，这个库也是公认的PHP下最好的图片处理库，完整代码放在最后；
NOTE2！！！
ThinkPHP 3.3.2(我用的版本)中自带的Imagick.class.php 在初始化图片的时候，调用的API有问题，会造成整个图片的大小改变：
在60行左右，需要做如下改变，才能对图片正常添加水印
//设置图像信息 $this->info = array( \'width\' => $info[0], \'height\' => $info[1], \'type\' => image_type_to_extension($info[2], false), \'mime\' => $info[\'mime\'], //下面自带的方法获取长宽会窄一点，造成gif缩放错误 // \'width\' => $this->img->getImageWidth(), // \'height\' => $this->img->getImageHeight(), // \'type\' => strtolower($this->img->getImageFormat()), // \'mime\' => $this->img->getImageMimeType(), );
对于生成图片，我封装了ImagickHelper.class.php，分享如下：
<?php /** * Created by PhpStorm. * User: m1881 * Date: 2016/12/3 * Time: 14:59 */ namespace Home\\Controller; class ImagickHelper { private $image = null; private $type = null; // 构造函数 public function __construct(){} // 析构函数 public function __destruct() { if($this->image!==null) $this->image->destroy(); } // 载入图像 public function open($path) { $this->image = new \\Imagick( $path ); if($this->image) { $this->type = strtolower($this->image->getImageFormat()); } return $this->image; } public function drawRect($draw){ $this->image->drawImage($draw); } public function crop($x=0, $y=0, $width=null, $height=null) { if($width==null) $width = $this->image->getImageWidth()-$x; if($height==null) $height = $this->image->getImageHeight()-$y; if($width<=0 || $height<=0) return; if($this->type==\'gif\') { $image = $this->image; $canvas = new \\Imagick(); $images = $image->coalesceImages(); foreach($images as $frame){ $img = new \\Imagick(); $img->readImageBlob($frame); $img->cropImage($width, $height, $x, $y); $canvas->addImage( $img ); $canvas->setImageDelay( $img->getImageDelay() ); $canvas->setImagePage($width, $height, 0, 0); } $image->destroy(); $this->image = $canvas; } else { $this->image->cropImage($width, $height, $x, $y); } } /* * 更改图像大小 $fit: 适应大小方式 \'force\': 把图片强制变形成 $width X $height 大小 \'scale\': 按比例在安全框 $width X $height 内缩放图片, 输出缩放后图像大小 不完全等于 $width X $height \'scale_fill\': 按比例在安全框 $width X $height 内缩放图片，安全框内没有像素的地方填充色, 使用此参数时可设置背景填充色 $bg_color = array(255,255,255)(红,绿,蓝, 透明度) 透明度(0不透明-127完全透明)) 其它: 智能模能 缩放图像并载取图像的中间部分 $width X $height 像素大小 $fit = \'force\',\'scale\',\'scale_fill\' 时： 输出完整图像 $fit = 图像方位值 时, 输出指定位置部分图像 字母与图像的对应关系如下: north_west north north_east west center east south_west south south_east */ public function resize_to($width = 100, $height = 100, $fit = \'center\', $fill_color = array(255,255,255,0) ) { switch($fit) { case \'force\': if($this->type==\'gif\') { $image = $this->image; $canvas = new \\Imagick(); $images = $image->coalesceImages(); foreach($images as $frame){ $img = new \\Imagick(); $img->readImageBlob($frame); $img->thumbnailImage( $width, $height, false ); $canvas->addImage( $img ); $canvas->setImageDelay( $img->getImageDelay() ); } $image->destroy(); $this->image = $canvas; } else { $this->image->thumbnailImage( $width, $height, false ); } break; case \'scale\': if($this->type==\'gif\') { $image = $this->image; $images = $image->coalesceImages(); $canvas = new \\Imagick(); foreach($images as $frame){ $img = new \\Imagick(); $img->readImageBlob($frame); $img->thumbnailImage( $width, $height, true ); $canvas->addImage( $img ); $canvas->setImageDelay( $img->getImageDelay() ); } $image->destroy(); $this->image = $canvas; } else { $this->image->thumbnailImage( $width, $height, true ); } break; case \'scale_fill\': $size = $this->image->getImagePage(); $src_width = $size[\'width\']; $src_height = $size[\'height\']; $x = 0; $y = 0; $dst_width = $width; $dst_height = $height; if($src_width*$height > $src_height*$width) { $dst_height = intval($width*$src_height/$src_width); $y = intval( ($height-$dst_height)/2 ); } else { $dst_width = intval($height*$src_width/$src_height); $x = intval( ($width-$dst_width)/2 ); } $image = $this->image; $canvas = new \\Imagick(); $color = \'rgba(\'.$fill_color[0].\',\'.$fill_color[1].\',\'.$fill_color[2].\',\'.$fill_color[3].\')\'; if($this->type==\'gif\') { $images = $image->coalesceImages(); foreach($images as $frame) { $frame->thumbnailImage( $width, $height, true ); $draw = new \\ImagickDraw(); $draw->composite($frame->getImageCompose(), $x, $y, $dst_width, $dst_height, $frame); $img = new \\Imagick(); $img->newImage($width, $height, $color, \'gif\'); $img->drawImage($draw); $canvas->addImage( $img ); $canvas->setImageDelay( $img->getImageDelay() ); $canvas->setImagePage($width, $height, 0, 0); } } else { $image->thumbnailImage( $width, $height, true ); $draw = new \\ImagickDraw(); $draw->composite($image->getImageCompose(), $x, $y, $dst_width, $dst_height, $image); $canvas->newImage($width, $height, $color, $this->get_type() ); $canvas->drawImage($draw); $canvas->setImagePage($width, $height, 0, 0); } $image->destroy(); $this->image = $canvas; break; default: $size = $this->image->getImagePage(); $src_width = $size[\'width\']; $src_height = $size[\'height\']; $crop_x = 0; $crop_y = 0; $crop_w = $src_width; $crop_h = $src_height; if($src_width*$height > $src_height*$width) { $crop_w = intval($src_height*$width/$height); } else { $crop_h = intval($src_width*$height/$width); } switch($fit) { case \'north_west\': $crop_x = 0; $crop_y = 0; break; case \'north\': $crop_x = intval( ($src_width-$crop_w)/2 ); $crop_y = 0; break; case \'north_east\': $crop_x = $src_width-$crop_w; $crop_y = 0; break; case \'west\': $crop_x = 0; $crop_y = intval( ($src_height-$crop_h)/2 ); break; case \'center\': $crop_x = intval( ($src_width-$crop_w)/2 ); $crop_y = intval( ($src_height-$crop_h)/2 ); break; case \'east\': $crop_x = $src_width-$crop_w; $crop_y = intval( ($src_height-$crop_h)/2 ); break; case \'south_west\': $crop_x = 0; $crop_y = $src_height-$crop_h; break; case \'south\': $crop_x = intval( ($src_width-$crop_w)/2 ); $crop_y = $src_height-$crop_h; break; case \'south_east\': $crop_x = $src_width-$crop_w; $crop_y = $src_height-$crop_h; break; default: $crop_x = intval( ($src_width-$crop_w)/2 ); $crop_y = intval( ($src_height-$crop_h)/2 ); } $image = $this->image; $canvas = new \\Imagick(); if($this->type==\'gif\') { $images = $image->coalesceImages(); foreach($images as $frame){ $img = new \\Imagick(); $img->readImageBlob($frame); $img->cropImage($crop_w, $crop_h, $crop_x, $crop_y); $img->thumbnailImage( $width, $height, true ); $canvas->addImage( $img ); $canvas->setImageDelay( $img->getImageDelay() ); $canvas->setImagePage($width, $height, 0, 0); } } else { $image->cropImage($crop_w, $crop_h, $crop_x, $crop_y); $image->thumbnailImage( $width, $height, true ); $canvas->addImage( $image ); $canvas->setImagePage($width, $height, 0, 0); } $image->destroy(); $this->image = $canvas; } } // 添加水印图片 public function add_watermark($path, $x = 0, $y = 0) { $watermark = new \\Imagick($path); $draw = new \\ImagickDraw(); $draw->composite($watermark->getImageCompose(), $x, $y, $watermark->getImageWidth(), $watermark->getimageheight(), $watermark); if($this->type==\'gif\') { $image = $this->image; $canvas = new \\Imagick(); $images = $image->coalesceImages(); foreach($image as $frame) { $img = new \\Imagick(); $img->readImageBlob($frame); $img->drawImage($draw); $canvas->addImage( $img ); $canvas->setImageDelay( $img->getImageDelay() ); } $image->destroy(); $this->image = $canvas; } else { $this->image->drawImage($draw); } } // 添加水印文字 public function add_text($text, $limit_width, $x = 0 , $y = 0, $angle=0, $style=array()) { //$width = $this->image->getImageWidth()-$x; //$height = $this->image->getImageHeight()-$y; //if($width<=0 || $height<=0) return; $draw = new \\ImagickDraw(); // $draw->setgravity(\\Imagick::GRAVITY_SOUTHWEST); if(isset($style[\'font\'])) $draw->setFont($style[\'font\']); if(isset($style[\'font_size\'])) $draw->setFontSize($style[\'font_size\']); //字体大小 if(isset($style[\'fill_color\'])) $draw->setFillColor($style[\'fill_color\']); // 字体颜色 // if(isset($style[\'under_color\'])) $draw->setTextUnderColor($style[\'under_color\']); //使文字换行 $text=$this->autowrap($style[\'font_size\'],$style[\'font\'],$text,$limit_width); if($this->type==\'gif\') { foreach($this->image as $frame) { $frame->annotateImage($draw, $x, $y, $angle, $text); } } els以上是关于ThinkPHP使用Imagick给图片加文字的主要内容，如果未能解决你的问题，请参考以下文章