PHP thumbnail generation class (supports imagemagick and gd libraries)-PHP Tutorial-php.cn

/** Thumbnail generation class, supports imagemagick and gd library processing
* Date: 2013-07-15
* Author: fdipzone
* Ver: 1.2
* edit: bbs.it-home.org
* Func:
* public set_config: Set parameters
* public create_thumb: Generate thumbnail image
* private fit: Thumbnail image
* private crop: Crop image
* private gd_fit: GD library thumbnail image
* private gd_crop: GD library crop image
* private get_size: get the size to be converted
* private get_crop_offset: get the offset of the crop
* private add_watermark: add watermark
* private check_handler: judgment processing Whether the program has been installed
* private create_dirs: Create a directory
* private exists: Determine whether the parameter exists
* private to_log: Record the log
* private hex2rgb: Convert hex color to rgb color
* private get_file_ext: Get the image type
*
* ver : 1.1 Added GD library processing
* ver: 1.2 Added width and height error parameter processing
* Added conversion to RGB processing when the image colorspace is not RGB
* Fixed the problem of transparent invalid area when using crop to save as gif, use +repage parameters, just delete the transparent invalid area
*
* tips: It is recommended to use imagemagick
* The GD library does not support transparency watermarks. If you must use transparent watermarks, please make the watermark image transparent.
* If the GD library outputs a gif with a transparent watermark, there will be problems.
*/
class PicThumb{ // class start
private $_log = null; // log file
private $_handler = null; // Program for image processing, imagemagick/gd library
private $_type = 'fit '; // fit or crop
private $_source = null; // Original image path
private $_dest = null; // Thumbnail path
private $_watermark = null; // Watermark image
private $_opacity = 75; / / Watermark image transparency, gd library does not support
private $_gravity = 'SouthEast'; // Watermark placement location NorthWest, North, NorthEast, West, Center, East, SouthWest, South, SouthEast
private $_geometry = '+10+ 10'; // Watermark positioning, gd library does not support
private $_croppos = 'TL'; // Screenshot location TL TM TR ML MM MR BL BM BR
private $_bgcolor = null; // Filled background color
private $_quality = 90; // Generated image quality
private $_width = null; // Specify area width
private $_height = null; // Specify area height
// Initialization
public function __construct($logfile=' '){
if($logfile!=''){
$this->_log = $logfile;
}
}
// Set parameters
public function set_config($param=array()){
$this->_handler = $this->exists($param, 'handler')? strtolower($param['handler']) : null;
$this->_type = $this->exists( $param, 'type')? strtolower($param['type']) : 'fit';
$this->_watermark = $this->exists($param, 'watermark')? $param[' watermark'] : null;
$this->_opacity = $this->exists($param, 'opacity')? $param['opacity'] : 75;
$this->_gravity = $this- >exists($param, 'gravity')? $param['gravity'] : 'SouthEast';
$this->_geometry = $this->exists($param, 'geometry')? $param[ 'geometry'] : '+10+10';
$this->_croppos = $this->exists($param, 'croppos')? $param['croppos'] : 'TL';
$this ->_bgcolor = $this->exists($param, 'bgcolor')? $param['bgcolor'] : null;
$this->_quality = $this->exists($param, 'quality ')? $param['quality'] : 90;
$this->_width = $this->exists($param, 'width')? $param['width'] : null;
$this- >_height = $this->exists($param, 'height')? $param['height'] : null;
}
/**Create thumbnail image
* @param String $source original image
* @param String $dest target image
* @return boolean
*/
public function create_thumb($source, $ dest){
// Check whether the handler used is installed
if(!$this->check_handler()){
$this->to_log('handler not installed');
return false;
}
// Determine whether the width and height of the area are correct
if(!is_numeric($this->_width) || !is_numeric($this->_height) || $this->_width<=0 || $this- >_height<=0){
$this->to_log('width or height invalid');
return false;
}
// Determine whether the source file exists
if(!file_exists($source)){
$this->to_log($source.' not exists');
return false;
}
// Create target file path
if(!$this->create_dirs($dest)){
$this ->to_log(dirname($dest).' create fail');
return false;
}
$this->_source = $source; // Source file
$this->_dest = $dest; // Target file
// Process the image
switch($this->_type){
case 'fit':
if($this->_handler=='imagemagick'){
return $this-> fit();
}else{
return $this->gd_fit();
}
break;
case 'crop':
if($this->_handler=='imagemagick'){
return $ this->crop();
}else{
return $this->gd_crop();
}
break;
default:
$this->to_log($this->_type.' not fit and crop');
return false;
}
}
/**Compress or stretch the image proportionally
* @return boolean
*/
private function fit(){
// Determine whether to fill the background
$bgcolor = ($this->_bgcolor!=null)?
sprintf(" -background '% s' -gravity center -extent '%sx%s' ", $this->_bgcolor, $this->_width, $this->_height) : "";
// Determine whether to convert to RGB
$source_info = getimagesize($this->_source);
$colorspace = (!isset($source_info['channels']) || $source_info['channels']!=3)? ' -colorspace RGB ' : '';
// Command line
$cmd = sprintf("convert -resize '%sx%s' '%s' %s -quality %s %s '%s'", $this->_width, $this->_height, $this->_source, $bgcolor, $this->_quality, $colorspace, $this->_dest);
// Record the executed command
$this->to_log ($cmd);
// Execute command
exec($cmd);
// Add watermark
$this->add_watermark($this->_dest);
return is_file($this-> _dest)? true : false;
}
/**Crop image
* @return boolean
*/
private function crop(){
// Get the generated image size
list($pic_w, $pic_h) = $this- >get_size();
// Get the offset of the screenshot
list($offset_w, $offset_h) = $this->get_crop_offset($pic_w, $pic_h);
// Determine whether to convert to RGB
$source_info = getimagesize($this->_source);
$colorspace = (!isset($source_info['channels']) || $source_info['channels']!=3)? ' -colorspace RGB ' : '';
// Command line
$cmd = sprintf("convert -resize '%sx%s' '%s' -quality %s %s -crop %sx%s+%s+%s +repage '%s '", $pic_w, $pic_h, $this->_source, $this->_quality, $colorspace, $this->_width, $this->_height, $offset_w, $offset_h, $this-> ;_dest);
// Record the executed command
$this->to_log($cmd);
// Execute the command
exec($cmd);
// Add watermark
$this->add_watermark ($this->_dest);
return is_file($this->_dest)? true : false;
}
/**GD library compresses or stretches images proportionally
* @return boolean
*/
private function gd_fit(){
/ / Get the generated image size
list($pic_w, $pic_h) = $this->get_size();
list($owidth, $oheight, $otype) = getimagesize($this->_source);
switch($otype){
case 1: $source_img = imagecreatefromgif($this->_source); break;
case 2: $source_img = imagecreatefromjpeg($this->_source); break;
case 3: $ source_img = imagecreatefrompng($this->_source); break;
default: return false;
}
// Shrink/stretch the image proportionally
$new_img = imagecreatetruecolor($pic_w, $pic_h);
imagecopyresampled( $new_img, $source_img, 0, 0, 0, 0, $pic_w, $pic_h, $owidth, $oheight);
// Determine whether to fill the background
if($this->_bgcolor!=null){
$bg_img = imagecreatetruecolor($this->_width, $this->_height);
$rgb = $this->hex2rgb($this->_bgcolor);
$bgcolor =imagecolorallocate($bg_img, $rgb ['r'], $rgb['g'], $rgb['b']);
imagefill($bg_img, 0, 0, $bgcolor);
imagecopy($bg_img, $new_img, (int)( ($this->_width-$pic_w)/2), (int)(($this->_height-$pic_h)/2), 0, 0, $pic_w, $pic_h);
$new_img = $ bg_img;
}
// Get the type of the target image
$dest_ext = $this->get_file_ext($this->_dest);
// Generate the image
switch($dest_ext){
case 1: imagegif ($new_img, $this->_dest, $this->_quality); break;
case 2: imagejpeg($new_img, $this->_dest, $this->_quality); break;
case 3 : imagepng($new_img, $this->_dest, (int)(($this->_quality-1)/10)); break;
}
if(isset($source_img)){
imagedestroy( $source_img);
}
if(isset($new_img)){
imagedestroy($new_img);
}
// Add watermark
$this->add_watermark($this->_dest);
return is_file($this->_dest)? true : false;
}
/**GD library crop image
* @return boolean
*/
private function gd_crop(){
// Get the generated image size
list($pic_w, $pic_h) = $this->get_size();
// Get the offset of the screenshot
list($offset_w, $offset_h) = $this->get_crop_offset($pic_w, $pic_h);
list($owidth, $oheight, $otype) = getimagesize($this-> ;_source);
switch($otype){
case 1: $source_img = imagecreatefromgif($this->_source); break;
case 2: $source_img = imagecreatefromjpeg($this->_source); break;
case 3: $source_img = imagecreatefrompng($this->_source); break;
default: return false;
}
// Shrink/stretch the image proportionally
$tmp_img = imagecreatetruecolor($pic_w, $pic_h );
imagecopyresampled($tmp_img, $source_img, 0, 0, 0, 0, $pic_w, $pic_h, $owidth, $oheight);
// Crop the picture
$new_img = imagecreatetruecolor($this->_width , $this->_height);
imagecopyresampled($new_img, $tmp_img, 0, 0, $offset_w, $offset_h, $this->_width, $this->_height, $this->_width, $ this->_height);
// Get the type of the target image
$dest_ext = $this->get_file_ext($this->_dest);
// Generate the image
switch($dest_ext){
case 1: imagegif($new_img, $this->_dest, $this->_quality); break;
case 2: imagejpeg($new_img, $this->_dest, $this->_quality); break;
case 3: imagepng($new_img, $this->_dest, (int)(($this->_quality-1)/10)); break;
}
if(isset($source_img)){
imagedestroy($source_img);
}
if(isset($tmp_img)){
imagedestroy($tmp_img);
}
if(isset($new_img)){
imagedestroy($new_img);
}
// Add watermark
$this->add_watermark($this->_dest);
return is_file($this->_dest)? true : false;
}
/**Get the size generated by the target image
* @return Array $width, $height
*/
private function get_size(){
list($owidth, $oheight) = getimagesize($this->_source);
$width = (int)($this->_width);
$height = ( int)($this->_height);
switch($this->_type){
case 'fit':
$pic_w = $width;
$pic_h = (int)($pic_w*$oheight/ $owidth);
if($pic_h>$height){
$pic_h = $height;
$pic_w = (int)($pic_h*$owidth/$oheight);
}
break;
case 'crop':
if($owidth>$oheight){
$pic_h = $height;
$pic_w = (int)($pic_h*$owidth/$oheight);
}else{
$pic_w = $width;
$pic_h = (int)($pic_w*$oheight/$owidth);
}
break;
}
return array($pic_w, $pic_h);
}
/**Get the offset of the screenshot
* @param int $pic_w Picture width
* @param int $pic_h Picture height
* @return Array $offset_w, $offset_h
*/
private function get_crop_offset($pic_w, $pic_h){
$offset_w = 0;
$offset_h = 0;
switch(strtoupper($this->_croppos)){
case 'TL':
$offset_w = 0;
$offset_h = 0;
break;
case 'TM':
$offset_w = (int)(($pic_w-$this->_width)/2);
$offset_h = 0;
break;
case 'TR':
$offset_w = (int)($pic_w-$this->_width);
$offset_h = 0;
break;
case 'ML':
$offset_w = 0;
$offset_h = (int)(($pic_h-$this->_height)/2);
break;
case 'MM':
$offset_w = (int)(($pic_w-$this->_width)/2);
$offset_h = (int)(($pic_h-$this->_height)/2);
break;
case 'MR':
$offset_w = (int)($pic_w-$this->_width);
$offset_h = (int)(($pic_h-$this->_height)/2);
break;
case 'BL':
$offset_w = 0;
$offset_h = (int)($pic_h-$this->_height);
break;
case 'BM':
$offset_w = (int)(($pic_w-$this->_width)/2);
$offset_h = (int)($pic_h-$this->_height);
break;
case 'BR':
$offset_w = (int)($pic_w-$this->_width);
$offset_h = (int)($pic_h-$this->_height);
break;
}
return array($offset_w, $offset_h);
}
/**Add watermark
* @param String $dest image path
*/
private function add_watermark($dest){
if($this->_watermark!=null && file_exists($this->_watermark) && file_exists($dest)){
list($owidth, $oheight, $otype) = getimagesize($dest);
list($w, $h, $wtype) = getimagesize($this->_watermark);
// 水印图比原图要小才加水印
if($w<=$owidth && $h<=$oheight){
if($this->_handler=='imagemagick'){ // imagemagick 添加水印
$cmd = sprintf("composite -gravity %s -geometry %s -dissolve %s '%s' %s %s", $this->_gravity, $this->_geometry, $this->_opacity, $this->_watermark, $dest, $dest);
$this->to_log($cmd);
exec($cmd);
}else{ // gd 添加水印
switch($wtype){
case 1: $water_img = imagecreatefromgif($this->_watermark); break;
case 2: $water_img = imagecreatefromjpeg($this->_watermark); break;
case 3: $water_img = imagecreatefrompng($this->_watermark); break;
default: return false;
}
switch($otype){
case 1: $dest_img = imagecreatefromgif($dest); break;
case 2: $dest_img = imagecreatefromjpeg($dest); break;
case 3: $dest_img = imagecreatefrompng($dest); break;
default: return false;
}
// 水印位置
switch(strtolower($this->_gravity)){
case 'northwest':
$posX = 0;
$posY = 0;
break;
case 'north':
$posX = ($owidth - $w) / 2;
$posY = 0;
break;
case 'northeast':
$posX = $owidth - $w;
$posY = 0;
break;
case 'west':
$posX = 0;
$posY = ($oheight - $h) / 2;
break;
case 'center':
$posX = ($owidth - $w) / 2;
$posY = ($oheight - $h) / 2;
break;
case 'east':
$posX = $owidth - $w;
$posY = ($oheight - $h) / 2;
break;
case 'southwest':
$posX = 0;
$posY = $oheight - $h;
break;
case 'south':
$posX = ($owidth - $w) / 2;
$posY = $oheight - $h;
break;
case 'southeast':
$posX = $owidth - $w;
$posY = $oheight - $h;
break;
}
imagealphablending($dest_img, true);
imagecopy($dest_img, $water_img, $posX, $posY, 0, 0, $w, $h);
switch($otype){
case 1:imagegif($dest_img, $dest, $this->_quality); break;
case 2:imagejpeg($dest_img, $dest, $this->_quality); break;
case 3:imagepng($dest_img, $dest, (int)(($this->_quality-1)/10)); break;
}
if(isset($water_img)){
imagedestroy($water_img);
}
if(isset($dest_img)){
imagedestroy($dest_img);
}
}
}
}
}
/**Determine whether the handler is installed
* @return boolean
*/
private function check_handler(){
$handler = $this->_handler;
if(!in_array($handler, array('imagemagick', 'gd', null))){
return false;
}
// 检查是否有安装imagemagick
$imagemagick_installed = strstr(shell_exec('convert -version'),'Version: ImageMagick')!=''? true : false;
// 检查是否有安装gd库
$gd_installed = function_exists('gd_info')? true : false;
switch($handler){
case 'imagemagick':
return $imagemagick_installed;
break;
case 'gd':
return $gd_installed;
break;
case null:
if($imagemagick_installed){
$this->_handler = 'imagemagick';
return true;
}
if($gd_installed){
$this->_handler = 'gd';
return true;
}
break;
}
return false;
}
/**Create image directory
* @param String $path
* @return boolean
*/
private function create_dirs($dest){
if(!is_dir(dirname($dest))){
return mkdir(dirname($dest), 0777, true);
}
return true;
}
/**Determine whether the parameter exists
* @param Array $obj array object
* @param String $key the key to be found
* @return boolean
*/
private function exists($obj,$key=''){
if($key==''){
return isset($obj) && !empty($obj);
}else{
$keys = explode('.',$key);
for($i=0,$max=count($keys); $i<$max; $i++){
if(isset($obj[$keys[$i]])){
$obj = $obj[$keys[$i]];
}else{
return false;
}
}
return isset($obj) && !empty($obj);
}
}
/**Record log
* @param String $msg The log message to be recorded
*/
private function to_log($msg){
if($this->_log){
$msg = '['.date('Y-m-d H:i:s').']'.$msg."rn";
file_put_contents($this->_log, $msg, FILE_APPEND);
}
}
/**hex color to rgb color
* @param String $color hex color
* @return Array
*/
private function hex2rgb($hexcolor){
$color = str_replace('#', '', $hexcolor);
if (strlen($color) > 3) {
$rgb = array(
'r' => hexdec(substr($color, 0, 2)),
'g' => hexdec(substr($color, 2, 2)),
'b' => hexdec(substr($color, 4, 2))
);
} else {
$r = substr($color, 0, 1) . substr($color, 0, 1);
$g = substr($color, 1, 1) . substr($color, 1, 1);
$b = substr($color, 2, 1) . substr($color, 2, 1);
$rgb = array(
'r' => hexdec($r),
'g' => hexdec($g),
'b' => hexdec($b)
);
}
return $rgb;
}
/**Get the image type
* @param String $file image path
* @return int
*/
private function get_file_ext($file){
$filename = basename($file);
list($name, $ext)= explode('.', $filename);
$ext_type = 0;
switch(strtolower($ext)){
case 'jpg':
case 'jpeg':
$ext_type = 2;
break;
case 'gif':
$ext_type = 1;
break;
case 'png':
$ext_type = 3;
break;
}
return $ext_type;
}
} // class end
?>
demo：
[php] view plaincopy
define('ROOT', dirname(__FILE__));
require(ROOT."/PicThumb.class.php");
$logfile = ROOT.'/PicThumb.log';
$source1 = ROOT.'/pic/source.jpg';
$dest1 = ROOT.'/pic/1.jpg';
$dest2 = ROOT.'/pic/2.gif';
$dest3 = ROOT.'/pic/3.png';
$source2 = ROOT.'/pic/source_cmyk.jpg';
$dest4 = ROOT.'/pic/4.jpg';
$dest5 = ROOT.'/pic/5.gif';
$dest6 = ROOT.'/pic/6.png';
$watermark = ROOT.'/pic/watermark.png';
// 按比例生成缩略图
$param = array(
'type' => 'fit',
'width' => 100,
'height' => 100,
);
$obj = new PicThumb($logfile);
$obj->set_config($param);
$flag = $obj->create_thumb($source1, $dest1);
if($flag){ // bbs.it-home.org
echo '';
}else{
echo 'create thumb fail';
}
// 按比例生成缩略图,不足部分用#FF0000填充
$param = array(
'type' => 'fit',
'width' => 100,
'height' => 100,
'bgcolor' => '#FFFF00'
);
$obj = new PicThumb($logfile);
$obj->set_config($param);
$flag = $obj->create_thumb($source1, $dest2);
if($flag){
echo '';
}else{
echo 'create thumb fail';
}
// 裁剪250x250的缩略图,裁剪位置是底部中间,水印位置西南,透明度50
$param = array(
'type' => 'crop',
'croppos' => 'BM',
'width' => 250,
'height' => 250,
'watermark' => $watermark,
'opacity' => 50,
'gravity' => 'SouthWest'
);
$obj = new PicThumb($logfile);
$obj->set_config($param);
$flag = $obj->create_thumb($source1, $dest3);
if($flag){
echo '';
}else{
echo 'create thumb fail';
}
// 按比例生成缩略图 CMYK格式
$param = array(
'type' => 'fit',
'width' => 100,
'height' => 100,
);
$obj = new PicThumb($logfile);
$obj->set_config($param);
$flag = $obj->create_thumb($source2, $dest4);
if($flag){
echo '';
}else{
echo 'create thumb fail';
}
// Generate thumbnails proportionally, fill the missing parts with #FF0000 in CMYK format
$param = array(
'type' => 'fit',
'width' => 100,
'height' => 100,
'bgcolor' => '#FFFF00'
);
$obj = new PicThumb($logfile);
$obj->set_config($param);
$flag = $obj->create_thumb($source2, $dest5);
if($flag){
echo '';
}else{
echo 'create thumb fail';
}
// Crop a 250x250 thumbnail, the cropping position is the bottom middle, the watermark position is southwest, and the transparency is 50 CMYK format
$param = array(
'type' => ; 'crop',
'croppos' => 'BM',
'width' => 250,
'height' => 250,
'watermark' => $watermark,
'opacity' => ; 50,
'gravity' => 'SouthWest'
);
$obj = new PicThumb($logfile);
$obj->set_config($param);
$flag = $obj->create_thumb ($source2, $dest6);
if($flag){
echo '';
}else{
echo 'create thumb fail';
}
?>

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