在PHP處理文字的過程中，imagettftext是一個給圖片添加水印的方式，可以動態指定字體、文字、大小，用起來比較方便；
在ThinkPHP中，可以方便地使用Imagick來完成相應的效果ImagickDraw.annotateImage,但是二者共同的問題是文字不能自動根據寬度換行；
解決的辦法就是計算文字的寬度，利用imagettfbox計算文字寬度，並且重構字符串在一些地方加入\n符號(http://php.net/manual/en/function.imagettfbbox.php#68518)
於是經過在網上的搜尋，整合出以下代碼：
/** * 返回一個字符的數組 * * @param $str 文字 * @param $charset 字符編碼 * @return $match 返回一個字符的數組 */ function charArray($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; } /** * 返回一個字符串在圖片中所占的寬度 * @param $fontsize 字體大小 * @param $fontangle 角度 * @param $ttfpath 字體文件 * @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; } /** * 根據預設寬度讓文字自動換行 * @param $fontsize 字體大小 * @param $ttfpath 字體名稱 * @param $str 字符串 * @param $width 預設寬度 * @param $fontangle 角度 * @param $charset 編碼 * @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，所以會有一些特殊的已經定義過的符號；
NOTE！！！
非常重要的一點，PHP里使用的文字單位不是像素，而是磅，所以會造成位置的偏差；
這個問題還沒有找到好的解決辦法，網上似乎也有二者的轉換方法，但是需要結合圖片分辨率吧，我記得我用了效果也不是很好；
/** * 實現php后台里，指定文字大小時，單位轉換 * @param $px * @return int */ function px2dp($px){ $map=array( 0,4, 5, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 21, 22, 23, 25, 26, 27, 28, 29, 30, 32, 33, 34, 35, 36, 38, 39, 40, 41, 43, 44, 46, 47, 48, 48, 50, 51); //遍歷數組 for($i=1;$i<count($map);$i++){ //恰好有匹配的磅值 if($map[$i]==$px){ return $i; } //如果當前像素值恰好在兩個磅值之間 if($map[$i]<$px && $map[$i+1]>$px){ return $i+0.5; } } } //附錄-->磅轉像素表 /* * 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 * */
並且我在項目中使用的是Imagick方式生成圖片，這個庫也是公認的PHP下最好的圖片處理庫，完整代碼放在最后；
NOTE2！！！
ThinkPHP 3.3.2(我用的版本)中自帶的Imagick.class.php 在初始化圖片的時候，調用的API有問題，會造成整個圖片的大小改變：
在60行左右，需要做如下改變，才能對圖片正常添加水印
//設置圖像信息 $this->info = array( 'width' => $info[0], 'height' => $info[1], 'type' => image_type_to_extension($info[2], false), 'mime' => $info['mime'], //下面自帶的方法獲取長寬會窄一點，造成gif縮放錯誤 // 'width' => $this->img->getImageWidth(), // 'height' => $this->img->getImageHeight(), // 'type' => strtolower($this->img->getImageFormat()), // 'mime' => $this->img->getImageMimeType(), );
對於生成圖片，我封裝了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 $type = null; // 構造函數 public function __construct(){} // 析構函數 public function __destruct() { if($this->image!==null) $this->image->destroy(); } // 載入圖像 public function open($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); } } /* * 更改圖像大小 $fit: 適應大小方式 'force': 把圖片強制變形成 $width X $height 大小 'scale': 按比例在安全框 $width X $height 內縮放圖片, 輸出縮放后圖像大小 不完全等於 $width X $height 'scale_fill': 按比例在安全框 $width X $height 內縮放圖片，安全框內沒有像素的地方填充色, 使用此參數時可設置背景填充色 $bg_color = array(255,255,255)(紅,綠,藍, 透明度) 透明度(0不透明-127完全透明)) 其它: 智能模能 縮放圖像並載取圖像的中間部分 $width X $height 像素大小 $fit = 'force','scale','scale_fill' 時： 輸出完整圖像 $fit = 圖像方位值 時, 輸出指定位置部分圖像 字母與圖像的對應關系如下: north_west north north_east west center east south_west south south_east */ public function resize_to($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 = $canvas; } } // 添加水印圖片 public function add_watermark($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']); //字體大小 if(isset($style['fill_color'])) $draw->setFillColor($style['fill_color']); // 字體顏色 // if(isset($style['under_color'])) $draw->setTextUnderColor($style['under_color']); //使文字換行 $text=$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); } } else { $this->image->annotateImage($draw, $x, $y, $angle, $text); } } // 保存到指定路徑 public function save_to( $path ) { if($this->type=='gif') { $this->image->writeImages($path, true); } else { $this->image->writeImage($path); } } // 輸出圖像 public function output($header = true) { if($header) header('Content-type: '.$this->type); echo $this->image->getImagesBlob(); } public function get_width() { $size = $this->image->getImagePage(); return $size['width']; } public function get_height() { $size = $this->image->getImagePage(); return $size['height']; } // 設置圖像類型， 默認與源類型一致 public function set_type( $type='png' ) { $this->type = $type; $this->image->setImageFormat( $type ); } // 獲取源圖像類型 public function get_type() { return $this->type; } // 當前對象是否為圖片 public function is_image() { if( $this->image ) return true; else return false; } public function thumbnail($width = 100, $height = 100, $fit = true){ $this->image->thumbnailImage( $width, $height, $fit ); } // 生成縮略圖 $fit為真時將保持比例並在安全框 $width X $height 內生成縮略圖片 /* 添加一個邊框 $width: 左右邊框寬度 $height: 上下邊框寬度 $color: 顏色: RGB 顏色 'rgb(255,0,0)' 或 16進制顏色 '#FF0000' 或顏色單詞 'white'/'red'... */ public function border($width, $height, $color='rgb(220, 220, 220)') { $color=new \ImagickPixel(); $color->setColor($color); $this->image->borderImage($color, $width, $height); } public function blur($radius, $sigma){ $this->image->blurImage($radius, $sigma); } // 模糊 public function gaussian_blur($radius, $sigma){ $this->image->gaussianBlurImage($radius, $sigma); } // 高斯模糊 public function motion_blur($radius, $sigma, $angle){ $this->image->motionBlurImage($radius, $sigma, $angle); } // 運動模糊 public function radial_blur($radius){ $this->image->radialBlurImage($radius); } // 徑向模糊 public function add_noise($type=null){ $this->image->addNoiseImage($type==null?imagick::NOISE_IMPULSE:$type); } // 添加噪點 public function level($black_point, $gamma, $white_point){$this->image->levelImage($black_point, $gamma, $white_point);} // 調整色階 public function modulate($brightness, $saturation, $hue){$this->image->modulateImage($brightness, $saturation, $hue);} // 調整亮度、飽和度、色調 public function charcoal($radius, $sigma){$this->image->charcoalImage($radius, $sigma);} // 素描 public function oil_paint($radius){$this->image->oilPaintImage($radius);} // 油畫效果 public function flop(){$this->image->flopImage();} // 水平翻轉 public function flip(){$this->image->flipImage();} // 垂直翻轉 /** * 返回一個字符的數組 * * @param $str 文字 * @param $charset 字符編碼 * @return $match 返回一個字符的數組 */ function charArray($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; } /** * 返回一個字符串在圖片中所占的寬度 * @param $fontsize 字體大小 * @param $fontangle 角度 * @param $ttfpath 字體文件 * @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; } /** * 根據預設寬度讓文字自動換行 * @param $fontsize 字體大小 * @param $ttfpath 字體名稱 * @param $str 字符串 * @param $width 預設寬度 * @param $fontangle 角度 * @param $charset 編碼 * @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; } }
然后調用方式如下：
try{ $image=new ImagickHelper(); $image->open($imgUrl); for($i=0;$i<count($width);$i++){ $this->addTexttoImg($image, $width[$i],$left[$i],$top[$i]+$font_size[$i], $text[$i],$color[$i], $font_family[$i],$font_size[$i]); } //加水印之后地址 $image->save_to($tumbUrl); }catch (Exception $e){ var_dump($e."Open save error"); $this->ajaxReturn(array( 'info' => '制作失敗', 'code' => 0 )); }
於是，以此方式可以完成ThinkPHP下Imagick給圖片加文字的任務~