function.php

<?php
	function ProcessImage($imgFile){
		global $db_server,$COEFFNUM;
	
		// Parse image
		list ($y_values, $i_values, $q_values) = ParseImage("img/".$imgFile);

		// Dempose and trunctate
		DecomposeImage($y_values);
		$y_trunc = TruncateCoeffs($y_values, $COEFFNUM);
		DecomposeImage($i_values);
		$i_trunc = TruncateCoeffs($i_values, $COEFFNUM);
		DecomposeImage($q_values);
		$q_trunc = TruncateCoeffs($q_values, $COEFFNUM);
		
		require 'config.php';

		// save image file
		$imageid = InsertFileToDB($imgFile,$y_values[0][0],$i_values[0][0],$q_values[0][0],$connection);

		// save y-coeffs
		InsertCoeffsToDB("coeffs_y",$y_trunc,$imageid);

		// save i-coeffs
		InsertCoeffsToDB("coeffs_i",$i_trunc,$imageid);

		// save q-coeffs
		InsertCoeffsToDB("coeffs_q",$q_trunc,$imageid);
		mysqli_close($connection);
	}

	function UploadImage($location){
		echo "Upload: " . $_FILES["file"]["name"] . "<br>";
    	echo "Type: " . $_FILES["file"]["type"] . "<br>";
    	echo "Size: " . ($_FILES["file"]["size"] / 1024) . " kB<br>";
    	echo "Temp file: " . $_FILES["file"]["tmp_name"] . "<br>";

		// check for errors
		if ($_FILES["file"]["error"] > 0){
	      exit("Return Code: " . $_FILES["file"]["error"] . "<br>");
	    }
		
		// get uploaded image
		$filepart = implode(explode(".",$_FILES["file"]["name"],-1));
		$explosion = explode(".", $_FILES["file"]["name"]);
		foreach ($explosion as $i){
			$extension = $i;
		}
		$extension = strtolower($extension);
		
		// size checks
		$image = imagecreatefromjpeg($_FILES["file"]["tmp_name"]);
		$image_width = imagesx($image);
		$image_height = imagesy($image);
		if ($image_height != 300 || $image_width != 300){
			exit("Size must be 300x 300");
		}

		// check type and extension
		$allowedExts = array("jpg", "jpeg", "gif", "png");
		if ((($_FILES["file"]["type"] != "image/gif")
			&& ($_FILES["file"]["type"] != "image/jpeg")
			&& ($_FILES["file"]["type"] != "image/png")
			&& ($_FILES["file"]["type"] != "image/pjpeg"))
		|| ($_FILES["file"]["size"] > 100000)
		|| !in_array($extension, $allowedExts)){
			exit("Invalid file");
		}

		// rename if necessary
		$filename = $filepart.".".$extension;
	    while (file_exists($location."/" . $filename)){
			$filename = $filepart."_".mt_rand(11,99).".".$extension;
	    }

		// all OK, copy image
	    move_uploaded_file($_FILES["file"]["tmp_name"], $location . "/" . $filename);
		return $filename;
	
	}

	// Parse image
	function ParseImage($imgFile){
		// read image
		$image = imagecreatefromjpeg($imgFile);
		$image_width = imagesx($image);
		$image_height = imagesy($image);

		// iterate through x axis
		for ($x = 0; $x < $image_width; $x++) {
			// iterate through y axis
			for ($y = 0; $y < $image_height; $y++) {
				// look at current pixel
				$rgb = imagecolorat($image, $x, $y);
				$r = (($rgb >> 16) & 0xFF) / 255;
				$g = (($rgb >> 8) & 0xFF) / 255;
				$b = ($rgb & 0xFF) / 255;
			
				// get YIQ values
				$y_values[$x][$y] = 0.299*$r + 0.587*$g + 0.114*$b; 
				$i_values[$x][$y] = 0.596*$r - 0.275*$g - 0.321*$b; 
				$q_values[$x][$y] = 0.212*$r - 0.523*$g + 0.311*$b; 	
			}
		}
		return array($y_values, $i_values, $q_values);
	}

	// insert file to database
	function InsertFileToDB($imgFile,$y_average,$i_average,$q_average,$connection){
		require 'config.php';
		$query = "INSERT INTO images VALUES(NULL,'".$imgFile."',".$y_average.",".$i_average.",".$q_average.")";

		$result = mysqli_query($connection,$query);
		if (!$result) die('Invalid query: ' . mysql_error());
			
		$result = mysqli_query($connection,"SELECT LAST_INSERT_ID()");
		while($row = mysqli_fetch_array($result))
			$last_id = $row[0];

		return $last_id;
	}

	// save coefficients
	function InsertCoeffsToDB($dbtable,$coefftable,$imageid){
		require 'config.php';
		global $COEFFNUM;
	
		$query = "INSERT INTO ".$dbtable." VALUES";
		for ($i = 0; $i < $COEFFNUM; $i++) {
			if ($i>0) $query.=",";
			$query.="(".$coefftable['x'][$i].",".$coefftable['y'][$i].",'".$coefftable['sign'][$i]."',".$imageid.")";
		}
		$result = mysqli_query($connection,$query);
		if (!$result) die('Invalid query: ' . mysql_error());
	}

	// Transpose table
	function transpose($array){
	    array_unshift($array, null);
	    return call_user_func_array('array_map', $array);
	}

	// Decompose Array
	function DecomposeArray(&$array){
		//get length
	    $h = count($array);
		
		// initialize array
		for ($x = 0; $x < $h; $x++) {
			$array[$x] = $array[$x] / sqrt($h);
		}
		
		// do the transformation
		while ($h > 1) {
			$h = $h /2;
			for ($i = 0; $i < $h; $i++) {
				$arraynew[$i]    = ($array[2*$i] + $array[2*$i+1])/sqrt(2);
				$arraynew[$h+$i] = ($array[2*$i] - $array[2*$i+1])/sqrt(2);
			}
			// copy arraynew to array
			for ($i = 0; $i < 2*$h; $i++) {
				$array[$i] = $arraynew[$i];
			}
		}
	}

	// Decompose Image
	function DecomposeImage(&$array){
		//get length
	    $rows = count($array);
		
		// decompose rows
		for ($x = 0; $x < $rows; $x++) {
			DecomposeArray($array[$x]);
		}
		
		// transpose matrix
		$array = transpose($array);
		
		// decompose rows again
		for ($x = 0; $x < $rows; $x++) {
			DecomposeArray($array[$x]);
		}
		
		// transpose matrix back
		$array = transpose($array);
	}

	// Truncate Coefficients - return array: x,y,sign
	function TruncateCoeffs($multi_array,$m){
		list ($abs_array, $sign_array) = TableToArrays($multi_array);
		arsort($abs_array);
		
		$i = 0;
		foreach ($abs_array as $key => $value){
			if ($i==$m)
				break;
				
			$coord = explode(",", $key);
				
			$trunc['x'][] = $coord[0];
			$trunc['y'][] = $coord[1];
			$trunc['sign'][] = $sign_array[$key];
			
			$i++;
		}
		return $trunc;
	}

	// Convert multi-dimensional array to array
	function TableToArrays($multi){
		foreach ($multi as $x => $array){
			foreach ($array as $y => $value){
				$key = $x.",".$y;
				$abs[$key] = abs($value);
				$sign[$key] = ($value > 0 ? "+" : "-");
			}
		}
		return array ($abs, $sign);
	}

	// Bin
	function bin($i,$j){
		return min(max($i,$j),5);
	}

	// Database Variables

	// Constant Variables

	$COEFFNUM = 40;
	$w['Y'] = array( 5.00, 0.83, 1.01, 0.52, 0.47, 0.30);
	$w['I'] = array(19.21, 1.26, 0.44, 0.53, 0.28, 0.14);
	$w['Q'] = array(34.37, 0.36, 0.45, 0.14, 0.18, 0.27);
?>