1、php在使用GD庫的時候應打開對應的GD庫擴展，如下圖

2、GD庫的開頭小案例

imagecreatetruecolor(width, height) 創建一個幕布

imagecolorallocate(handle, red, green, blue) 定義一個顏色

imagecolortransparent(handle, color) 把顏色設置為透明顏色， 第二個參數為imagecolorallocate對象的顏色

imagefill(handle, x, y, color) 填充幕布的顏色

1 <?php 2 header('content-type:image/png'); 3 ini_set('display_errors', true); 4 //創建畫布，并且指定寬高 5 $handle = imagecreatetruecolor(300, 200); 6 //給畫布創建顏色 7 $bgColor = imagecolorallocate($handle, 200,15,16); 8 //把顏色從(0,0)點開始填充到畫布 9 imagefill($handle, 0,0, $bgColor); 10 //繪制直線 11 $lineColor = imagecolorallocate($handle, 200,200,200); 12 //參數二表示起點的x軸坐標 13 //參數三表示起點的Y軸坐標 14 //參數四表示終點的x軸坐標 15 //參數五表示終點的Y軸坐標 16 imageline($handle, 0,0,100,200, $lineColor); 17 //輸出 18 imagepng($handle); 19 //銷毀圖像 20 imagedestroy($handle); 21 ?>

?3、使用GD庫繪制矩形

<?php header('content-type:image/png'); ini_set('display_errors', true); $handle = imagecreatetruecolor(300, 200); $bgColor = imagecolorallocate($handle, 50, 150, 250); imagefill($handle, 0, 0, $bgColor); $rectColor = imagecolorallocate($handle, 232, 16, 16); //繪制一個描邊的矩形 //第二個參數表示 imagerectangle($handle, 50, 50, 150, 150, $rectColor); //繪制一個填充的矩形 imagefilledrectangle($handle, 180, 50, 280, 150, $rectColor); imagepng($handle); imagedestroy($handle); ?>

?4、使用GD庫繪制圓形

<?php header('content-type:image/png'); ini_set('display_errors', true); $handle = imagecreatetruecolor(400, 200); $bgColor = imagecolorallocate($handle, 200,20,50); imagefill($handle, 0, 0, $bgColor); $color = imagecolorallocate($handle, 132, 209, 73); //繪制邊軭的圓 imageellipse($handle, 100,100, 100, 100, $color); //繪制填充的圓 imagefilledellipse($handle, 300, 100, 100 ,100, $color); imagepng($handle); imagedestroy($handle); ?>

?5、使用圖片的復制功能

imagesx($handle)? 可以獲取圖片的寬度

imagesy($handle) 可以獲取圖片的高度

getimagesize($filename) 可以獲取圖片的大小，類型等相關的信息

imagecopyresampled($dsimage, $srcimage, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h);? 復制圖片并且調整大小

<?php header('content-type:image/png'); ini_set('display_errors', true); $handle = imagecreatetruecolor(400, 200); $bgColor = imagecolorallocate($handle, 255, 255, 153); imagefill($handle, 0, 0, $bgColor); //獲取需要復制的原圖 $source = imagecreatefrompng('test.png'); //獲取原圖的寬 $imagex = imagesx($source); //獲取原圖的高 $imagey = imagesy($source); //執行圖片的復制 //參數1表示目標圖片 //參數2表示原圖資源 //參數3，4表示目標圖片起始x,y點 //參數5，6表示原圖圖片的起始x,y點 //參數7，8表示圖片的寬高 imagecopy($handle, $source, 0, 0, 0, 0, $imagex, $imagey); imagepng($handle); imagedestroy($handle); ?>

?6、GD庫繪制字符串與文字

?imagestring => 不能指定繪制的字體

?imagettftext =>? 可以指定繪制的字體

imagepng($handle, $newFileName) 當沒有newFileName的時候會以圖片的形式輸出，當有第二個參數時，會保存到指定的文件里

imagegif,imagejpeg的用法如上

<?php header('content-type:image/png'); ini_set('display_errors', true); $handle = imagecreatetruecolor(400, 200); $bgColor = imagecolorallocate($handle, 255, 200, 10); imagefill($handle, 0, 0, $bgColor); $fontColor = imagecolorallocate($handle, 0, 0, 160); //繪制字體 //參數二表示，字體的大小，但是似乎沒有多大的用處 //參數三和參數四表示，字體開始的起點的x軸和Y軸坐標 //參數五表示，需要繪制的內容 //參數六表示，字體的顏色 //注意，因為這個函數不能指定字體以及更多的屬性，因此更多的是使用imagettftext這個函數 imagestring($handle, 100, 10, 10, 'are you ok???',$fontColor); imagepng($handle); imagedestroy($handle); ?> <?php header('content-type: image/png'); ini_set('display_errors', true); $handle = imagecreatetruecolor(400, 200); $bgColor = imagecolorallocate($handle, 200, 230, 20); imagefill($handle, 0, 0, $bgColor); $fontColor = imagecolorallocate($handle, 200, 0, 200); //參數二：表示字體的大小 //參數三：表示字體的旋轉角度 //參數四：表示起始的X軸起點 //參數五：表示起始的Y軸起點 //參數六：表示字體的顏色 //參數七：表示字體文件的路徑 //參數八：表示渲染的內容 imagettftext($handle, 30, 20, 100, 150, $fontColor, './resource/STHUPO.TTF', 'hello world'); imagepng($handle); imagedestroy($handle); ?>

?7、GD庫繪制弧形

<?php header('content-type:image/png'); ini_set('display_errors', true); $handle = imagecreatetruecolor(400, 200); $bgColor = imagecolorallocate($handle, 200, 200, 10); imagefill($handle, 0, 0, $bgColor); $lineColor = imagecolorallocate($handle, 255, 0, 255); //參數二，三：表示圓心的X軸坐標，Y軸坐標 //參數四，五：表示弧度的寬和高 //參數六，七：表示弧度的起點和終點，（起點表示三點鐘方向） //參數八：表示線條的顏色 imagearc($handle, 100, 100, 100, 100, 0, 180, $lineColor); //其他參數和上面的函數一樣，最后一個參數表示類型，也可以用0表示 imagefilledarc($handle, 300, 100, 100,100, 90, 270, $lineColor,IMG_ARC_PIE); imagepng($handle); imagedestroy($handle); ?>

?8、用GD庫繪制點

<?php header('content-type: image/png'); ini_set('display_errors', true); $handle = imagecreatetruecolor(400, 200); $bgColor = imagecolorallocate($handle, 200, 200, 150); imagefill($handle, 0, 0, $bgColor); for ($i = 0; $i < 10000; $i++) {$dotColor = imagecolorallocate($handle, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));//創建點//第二個參數和第三個參數分別表示點的x軸和y軸坐標//參數四表示點的顏色imagesetpixel($handle, mt_rand(0, 400), mt_rand(0, 200), $dotColor); } imagepng($handle); imagedestroy($handle); ?>

?9、封裝生成驗證碼的類

<?php ini_set('display_errors', true);class Captcha {private $config = ['width' => 100, //畫布的寬'height' => 30, //畫布的高'number' => 4, //生成隨機數的數量'font' => './resource/STHUPO.TTF', //驗證碼的字體'fontSize' => 18, //字體大小'content' => []];private $handle; //驗證碼句柄public function __construct(array $conf = []) {$this->config = array_replace($this->config, $conf);empty($this->config['content'])? $this->config['content'] = $this->fillText(): null; //如果沒有內容，那么要創造內容 }public function init() {header('content-type: image/png');$this->createPng();$this->createText();$this->createDot();$this->createLine();imagepng($this->handle);imagedestroy($this->handle);}/**創建文字* @return array*/private function fillText() {return $content = array_merge(range('a', 'z'), range('A', 'Z'), range(3,9));}/*** 創建幕布*/private function createPng() {$this->handle = imagecreatetruecolor($this->config['width'], $this->config['height']);$bgColor = imagecolorallocate($this->handle, mt_rand(100, 200), mt_rand(100, 200), mt_rand(100, 200));imagefill($this->handle, 0, 0, $bgColor);}/*** 創建字體*/private function createText() {$space = $this->config['width'] / (1+$this->config['number']);for($i = 0; $i < $this->config['number']; $i ++) {$fontColor = imagecolorallocate($this->handle, mt_rand(0,100), mt_rand(0,100), mt_rand(0,100));$text = $this->config['content'][mt_rand(0, count($this->config['content'])-1)];$height = ($this->config['height'] + $this->config['fontSize']) / 2;$width = ($i+1) * $space - $this->config['fontSize'] /2;imagettftext($this->handle, $this->config['fontSize'], mt_rand(-30, 30), $width, $height, $fontColor, $this->config['font'], $text);}}/*** 畫干擾點*/private function createDot() {for($i = 0; $i < 100; $i ++) {$dotColor = imagecolorallocate($this->handle, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255));imagesetpixel($this->handle, mt_rand(0, $this->config['width']), mt_rand(0, $this->config['height']), $dotColor);}}/*** 繪制曲直干擾線*/private function createLine() {for($i = 0; $i < 5; $i ++) {$lineColor = imagecolorallocate($this->handle, mt_rand(0,100), mt_rand(0, 100), mt_rand(0, 100));imageline($this->handle, mt_rand(0, $this->config['width']), mt_rand(0, $this->config['height']), mt_rand(0, $this->config['width']), mt_rand(0, $this->config['height']), $lineColor);imagearc($this->handle, mt_rand(0, $this->config['width']), mt_rand(0, $this->config['height']), mt_rand(0, $this->config['width']), mt_rand(0, $this->config['height']), mt_rand(0, 360), mt_rand(0, 360), $lineColor);}}}$c = new Captcha(['content'=> ['你','我','他', '是', '給'], // 'fontSize' => 12, ]); $c->init();?>

?10、在上傳圖片上添加水印的類（PHP部份）

<?php header('content-type:text/html;charset=utf-8'); ini_set('display_errors', true); class UploadFile {private $file;private $allowType = ['image/png', 'image/jpg', 'image/jpeg'];private $limitSize = 3*1024*1024;private $targetPath = 'd:/uploadFile';public function __construct() {if($_FILES['file']['error'] === 4) {die('請上傳文件');}$this->file = $_FILES['file'];}private function getExtension() {return substr(strrchr($this->file['name'], '.'), 1);}private function getNewFile() {$file = sprintf('%s/%s',$this->targetPath, date('Ymd'));if(!file_exists($file)) {mkdir($file, 0777, true);}return $file;}private function getNewFileName() {return sprintf('%s/%s.%s', $this->getNewFile(), uniqid('up_', true),$this->getExtension());}private function checkFileType() {$finfo = new finfo(FILEINFO_MIME_TYPE);$type =$finfo->file($this->file['tmp_name']);return in_array($type, $this->allowType) && in_array($this->file['type'], $this->allowType);}private function checkFileSize() {return $this->file['size'] <= $this->limitSize;}/**實現圖片的水印* @param $file* @param $newFileName* @return bool*/private function printLogo($file, $newFileName) {$ext = $this->getExtension();$handle = null;switch(strtolower($ext)) {case 'jpg' || 'jpeg': $handle = imagecreatefromjpeg($file);break;case 'png': $handle = imagecreatefrompng($file);break;}$fontColor = imagecolorallocate($handle, 0, 0, 0);imagettftext($handle, 40,-30, 100, 100, $fontColor,'./resource/STHUPO.TTF', 'are you ok???');$res = imagejpeg($handle, $newFileName);imagedestroy($handle);return $res;}public function init() {if(is_uploaded_file($this->file['tmp_name'])) {!$this->checkFileType() ? die(sprintf('上傳的類型錯誤，只允許上傳%s類型的文件', implode(',', $this->allowType))): null;!$this->checkFileSize() ? die(sprintf('上傳的大小錯誤，只允許上傳%d大小的文件', $this->limitSize)): null;$fileName = $this->getNewFileName();if($this->printLogo($this->file['tmp_name'], $fileName)) {echo '上傳成功';} else {echo '上傳失敗';}} else {echo 'unknow';}} }$u = new UploadFile(); $u->init(); ?>

html部份

<!doctype html> <html lang="en"> <head><meta charset="UTF-8"><meta name="viewport"content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0"><meta http-equiv="X-UA-Compatible" content="ie=edge"><title>test</title> </head> <body> <form action="./test.php" method="post" enctype="multipart/form-data"><input type="file" name="file"><input type="submit" value="提交"> </form> </body> </html>

?11、圖像的壓縮

?介紹：在圖像上傳后，一般不直接使用圖片，因為圖片往往過大，一般通過等比例壓縮后再使用

<?php header('content-type:text/html; charset=utf-8'); ini_set('display_errors', true);class ThumbPress{private $handle; //原圖的句柄private $type; //文件類型private $src_width; //原圖的寬private $src_height; //原圖的高private $limitType = ['image/png', 'image/jpg', 'image/jpeg', 'image/gif'];private $imageCreate = ['imagecreatefrompng', 'imagecreatefromjpeg', 'imagecreatefromjpeg', 'imagecreatefromgif'];private $imageOutPut = ['imagepng', 'imagejpeg', 'imagejpeg', 'imagegif'];private $config = ['width' => 50,'height' => 50,'text' => '','fontSize' => 20,'font' => './resource/STHUPO.TTF','targetFile' => 'd:/uploadFile/thumbImg'];public function __construct($conf) {$this->config = array_replace($this->config, $conf);if(file_exists($this->config['filename']) && in_array($this->type = mime_content_type($this->config['filename']), $this->limitType)) {$this->handle = array_combine($this->limitType, $this->imageCreate)[$this->type]($this->config['filename']);}}/**計算縮放比率* @return float|int*/private function getScaleBite() {$scale = 1;$this->src_width = imagesx($this->handle);$this->src_height = imagesy($this->handle);switch(true) {case $this->src_width >= $this->src_height: $scale = $this->src_width / $this->config['width']; break;case $this->src_width < $this->src_height: $scale = $this->src_height / $this->config['hegiht']; break;}return $scale;}/**創建新圖片的幕布* @return false|resource*/private function createScreen() {$screen = imagecreatetruecolor($this->config['width'], $this->config['height']);$color = imagecolorallocate($screen, 255, 255, 255);$color = imagecolortransparent($screen, $color);imagefill($screen, 0, 0, $color);return $screen;}/**創建圖片新名字，生成新地址* @return string*/private function createFilePath(): string {$name = sprintf('thumb_%s', basename($this->config['filename']));if(!file_exists($this->config['targetFile'])) {mkdir($this->config['targetFile'], 0777, true);}return sprintf('%s/%s', $this->config['targetFile'], $name);}/**打印水印* @param $screen*/private function printLogo($screen) {if(!$this->config['text']) {return;}$fontColor = imagecolorallocate($screen, 0, 0, 0);imagettftext($screen, $this->config['fontSize'], 0, 20, 20, $fontColor, $this->config['font'], $this->config['text']);}/**壓縮圖片* @return string*/private function imageThumb(): string {$screen = $this->createScreen();$scale = $this->getScaleBite();$newFileName = $this->createFilePath();$targetWidth = $this->src_width / $scale;$targetHeight = $this->src_height / $scale;imagecopyresampled($screen, $this->handle,0,0,0,0, $targetWidth, $targetHeight, $this->src_width, $this->src_height);$this->printLogo($screen);array_combine($this->limitType, $this->imageOutPut)[$this->type]($screen, $newFileName); //輸出圖片return $newFileName; //返回新圖片的名字 }public function init() {if(!$this->handle) {return false;}return $this->imageThumb();} }?>

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轉載于:https://www.cnblogs.com/rickyctbu/p/10924986.html

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