PHP 图片处理

 /** * 获取图片的Base64编码(不支持url) * @param $img_file 传入本地图片地址 * @return string */ function imgToBase64($img_file) { $img_base64 = ''; if (file_exists($img_file)) { $app_img_file = $img_file; // 图片路径 $img_info = getimagesize($app_img_file); // 取得图片的大小，类型等 //echo '
' . print_r($img_info, true) . '

'; list($width, $height, $type, $attr) = getimagesize($app_img_file); $fp = fopen($app_img_file, "r"); // 图片是否可读权限 if ($fp) { $filesize = filesize($app_img_file); $content = fread($fp, $filesize); $file_content = chunk_split(base64_encode($content)); // base64编码 switch ($type) {   //判读图片类型 case 1: $img_type = "gif"; break; case 2: $img_type = "jpg"; break; case 3: $img_type = "png"; break; } $img_base64 = 'data:image/png;base64,' . $file_content;//合成图片的base64编码 } fclose($fp); }else{ return $img_file; } return $img_base64; //返回图片的base64 }

 /** * 图片旋转 * @param $src 图片地址 * @param $direction 1顺时针90 2 逆时针90 * @return string */ function imgturn($src, $direction = 1){ $ext = pathinfo($src)['extension']; switch ($ext) { case 'gif': $img = imagecreatefromgif($src); break; case 'jpg': case 'jpeg': $img = imagecreatefromjpeg($src); break; case 'png': $img = imagecreatefrompng($src); break; default: die('图片格式错误!'); break; } $width = imagesx($img); $height = imagesy($img); $img2 = imagecreatetruecolor($height, $width); //顺时针旋转90度 if($direction == 1){ for ($x = 0; $x <$width; $x++) { for($y=0; $y<$height; $y++) { imagecopy($img2, $img, $height - 1 - $y, $x, $x, $y, 1, 1); } } }else if($direction == 2) { //逆时针旋转90度 for ($x = 0; $x <$height; $x++) { for($y = 0; $y <$width; $y++) { imagecopy($img2, $img, $x, $y, $width - 1 - $y, $x, 1, 1); } } } switch ($ext) { case 'jpg': case "jpeg": imagejpeg($img2, $src, 100); break; case "gif": imagegif($img2, $src, 100); break; case "png": imagepng($img2, $src, 100); break; default: die('图片格式错误!'); break; } imagedestroy($img); imagedestroy($img2); }

 /** * 图片压缩处理 * @param string $sFile 源图片路径 * @param int $iWidth 自定义图片宽度 * @param int $iHeight 自定义图片高度 * @return string 压缩后的图片路径 */ function getThumb($sFile, $iWidth, $iHeight){ //图片公共路径 $public_path = ''; //判断该图片是否存在 if(!file_exists($public_path . $sFile)) return $sFile; list($width, $height, $type, $attr) = getimagesize($sFile); if($width <$height){ imgturn($sFile, 2); } //判断图片格式(图片文件后缀) $extend = explode("." , $sFile); $attach_fileext = strtolower($extend[count($extend) - 1]); if (!in_array($attach_fileext, array('jpg','png','jpeg'))){ return ''; } //压缩图片文件名称 $sFileNameS = str_replace("." . $attach_fileext, "_" . $iWidth . '_' . $iHeight . '.' . $attach_fileext, $sFile); //判断是否已压缩图片，若是则返回压缩图片路径 if(file_exists($public_path . $sFileNameS)){ return $sFileNameS; } //生成压缩图片，并存储到原图同路径下 resizeImage($public_path . $sFile, $public_path . $sFileNameS, $iWidth, $iHeight); if(!file_exists($public_path . $sFileNameS)){ return $sFile; } return $sFileNameS; }

 /** * 生成图片 * @param string $im 源图片路径 * @param string $dest 目标图片路径 * @param int $maxwidth 生成图片宽 * @param int $maxheight 生成图片高 */ function resizeImage($im, $dest, $maxwidth, $maxheight) { $img = getimagesize($im); switch ($img[2]) { case 1: $im = @imagecreatefromgif($im); break; case 2: $im = @imagecreatefromjpeg($im); break; case 3: $im = @imagecreatefrompng($im); break; } $pic_width = imagesx($im); $pic_height = imagesy($im); $resizewidth_tag = false; $resizeheight_tag = false; if (($maxwidth && $pic_width > $maxwidth) || ($maxheight && $pic_height > $maxheight)) { if ($maxwidth && $pic_width > $maxwidth) { $widthratio = $maxwidth / $pic_width; $resizewidth_tag = true; } if ($maxheight && $pic_height > $maxheight) { $heightratio = $maxheight / $pic_height; $resizeheight_tag = true; } if ($resizewidth_tag && $resizeheight_tag) { if ($widthratio <$heightratio){ $ratio = $widthratio; }else{ $ratio = $heightratio; } } if ($resizewidth_tag && !$resizeheight_tag){ $ratio = $widthratio; } if ($resizeheight_tag && !$resizewidth_tag){ $ratio = $heightratio; } $newwidth = $pic_width * $ratio; $newheight = $pic_height * $ratio; if (function_exists("imagecopyresampled")) { $newim = imagecreatetruecolor($newwidth, $newheight); imagecopyresampled($newim, $im, 0, 0, 0, 0, $newwidth, $newheight, $pic_width, $pic_height); } else { $newim = imagecreate($newwidth, $newheight); imagecopyresized($newim, $im, 0, 0, 0, 0, $newwidth, $newheight, $pic_width, $pic_height); } imagejpeg($newim, $dest); imagedestroy($newim); } else { imagejpeg($im, $dest); } }