試著上傳一張照片看看吧

HTML

<form id="upload-form" action="crop.php" method="POST" enctype="multipart/form-data">
	<input type="file" name="aafile"/>
	<button type="submit" id="save-pic" class="btn btn-primary btn-large">上傳圖片</button>
</form>

PHP

<?php 
	$file = 'aafile';
	$id = 5;
	$upload_dir = './';
	$output_size = array(
		'background'=>array('output_w'=>720, 'output_h'=>1360),
		'thumb'=>array('output_w'=>100, 'output_h'=>80)
	);

	if (isset($_FILES[$file])){
		if(is_uploaded_file($_FILES[$file]['tmp_name'])){
			centerCropSave($file,$upload_dir,$id,$output_size);
		}
	}	

	function centerCropSave($file, $upload_dir, $id, $output_size){
		$fileSource = $_FILES[$file];
		$fileExt = $fileSource['type'];

		if($fileExt == 'image/jpeg'){
			$fileType=".jpg";
		}elseif($fileExt == 'image/gif'){
			$fileType=".gif";
		}elseif($fileExt == 'image/png'){
			$fileType=".png";
		}else{
			exit;
		}

		if($fileType == ".jpg"){
			$src = imagecreatefromjpeg($fileSource['tmp_name']);
		}elseif($fileType == ".gif"){
			$src = imagecreatefromgif($fileSource['tmp_name']);
		}elseif($fileType == ".png"){
			$src = imagecreatefrompng($fileSource['tmp_name']);
		}

		//轉向?
		$exif = exif_read_data($fileSource['tmp_name']);
		if (!empty($exif['Orientation'])) {
			switch ($exif['Orientation']) {
				case 3:
					$src = imagerotate($src, 180, 0);
					break;
				case 6:
					$src = imagerotate($src, -90, 0);
					break;
				case 8:
					$src = imagerotate($src, 90, 0);
					break;
			}
		}

		//取得來源圖片長寬
		$src_w = imagesx($src);
		$src_h = imagesy($src);

		foreach ($output_size as $dir_key => $dir_value) {
			$photo_dir = $upload_dir.$dir_key;

			$output_w = $dir_value['output_w'];
			$output_h = $dir_value['output_h'];

			$src_ratio = $src_w / $src_h;
			$output_ratio = $output_w / $output_h;
			
			if ( $src_ratio > $output_ratio ){
				// Triggered when source image is wider
				$temp_height = $output_h;
				$temp_width = ( int ) ( $output_h * $src_ratio );
			} else {
				// Triggered otherwise (i.e. source image is similar or taller)
				$temp_width = $output_w;
				$temp_height = ( int ) ( $output_w / $src_ratio );
			}
			
			// Resize the image into a temporary GD image
			$temp_gdim = imagecreatetruecolor( $temp_width, $temp_height );
			imagecopyresampled(
				$temp_gdim,
				$src,
				0, 0,
				0, 0,
				$temp_width, $temp_height,
				$src_w, $src_h
			);

			// Copy cropped region from temporary image into the desired GD image
			$x0 = ( $temp_width - $output_w ) / 2;
			$y0 = ( $temp_height - $output_h ) / 2;

			$desired_gdim = imagecreatetruecolor( $output_w, $output_h );
			imagecopy(
				$desired_gdim,
				$temp_gdim,
				0, 0,
				$x0, $y0,
				$output_w, $output_h
			);
			imagejpeg($desired_gdim, $photo_dir.'/'.$id.'.jpg', 100);
			//echo $photo_dir.'/'.$id.'.jpg<br/>';
			//echo '<img src="'.$photo_dir.'/'.$id.'.jpg"/>';
			//echo '<hr/>';					
		}
	}
?>