asifulmamun · July 9, 2025 05:42
diff --git a/Huffman Coding | Greedy Algorithm | DSA | PHP b/Huffman Coding | Greedy Algorithm | DSA | PHP
 <?php
    if ($_SERVER['REQUEST_METHOD'] == 'POST' && isset($_FILES['image'])) {
        $image = $_FILES['image']['tmp_name'];
        $imageData = file_get_contents($image);
        $base64 = base64_encode($imageData);


        $data = $base64;
    }
 ?>

 <!DOCTYPE html>
 <html lang="en">
 <head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link href="https://cdn.jsdelivr.net/npm/[email protected]/dist/tailwind.min.css" rel="stylesheet">
 </head>
 <body class="bg-gray-100 text-gray-900">
    <form method="post" enctype="multipart/form-data" class="flex flex-col items-center p-4 bg-white shadow-md rounded-lg">
        <input type="file" name="image" accept="image/*" class="mb-4 p-2 border border-gray-300 rounded">
        <button type="submit" class="px-4 py-2 bg-blue-500 text-white rounded hover:bg-blue-700">Upload Image</button>
    </form>

    <?php
        
        $data = gzcompress($base64);

    ?>

 <?php

 class HuffmanNode {
    public $char;
    public $freq;
    public $left;
    public $right;

    public function __construct($char, $freq, $left = null, $right = null) {
        $this->char = $char;
        $this->freq = $freq;
        $this->left = $left;
        $this->right = $right;
    }
 }

 // frequency count
 function calculateFrequency($text) {
    return array_count_values(str_split($text));
 }

 // Huffman Tree create
 function buildHuffmanTree($freq) {
    $heap = new SplPriorityQueue();
    
    foreach ($freq as $char => $f) {
        $heap->insert(new HuffmanNode($char, $f), -$f);
    }

    while ($heap->count() > 1) {
        $left = $heap->extract();
        $right = $heap->extract();
        $newNode = new HuffmanNode(null, $left->freq + $right->freq, $left, $right);
        $heap->insert($newNode, -$newNode->freq);
    }

    return $heap->extract();
 }

 // Huffman code generation
 function generateCodes($node, $prefix = "", &$codes = []) {
    if ($node == null) return;
    
    if ($node->char !== null) {
        $codes[$node->char] = $prefix;
    }

    generateCodes($node->left, $prefix . "0", $codes);
    generateCodes($node->right, $prefix . "1", $codes);
 }

 // encode
 function encode($text, $codes) {
    $encodedText = "";
    foreach (str_split($text) as $char) {
        $encodedText .= $codes[$char];
    }
    return $encodedText;
 }

 // decode
 function decode($encodedText, $tree) {
    $decodedText = "";
    $node = $tree;

    foreach (str_split($encodedText) as $bit) {
        $node = ($bit == '0') ? $node->left : $node->right;

        if ($node->char !== null) {
            $decodedText .= $node->char;
            $node = $tree;
        }
    }

    return $decodedText;
 }

 // test
 $text = $data;
 $freq = calculateFrequency($text);
 $tree = buildHuffmanTree($freq);
 $codes = [];
 generateCodes($tree, "", $codes);
 $encodedText = encode($text, $codes);
 $decodedText = decode($encodedText, $tree);


 // echo "Original Text: $text\n";
 // echo "Encoded Text: $encodedText\n";
 // echo "Decoded Text: $decodedText\n";



 ?>

    <div class="flex flex-col items-center p-4 bg-white shadow-md rounded-lg">
        <div class="break-words">
            <?php echo $encodedText; ?>
        </div>
    </div>

    

 </body>
 </html>
	<?php
	if ($_SERVER['REQUEST_METHOD'] == 'POST' && isset($_FILES['image'])) {
	$image = $_FILES['image']['tmp_name'];
	$imageData = file_get_contents($image);
	$base64 = base64_encode($imageData);


	$data = $base64;
	}
	?>

	<!DOCTYPE html>
	<html lang="en">
	<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<title>Document</title>
	<link href="https://cdn.jsdelivr.net/npm/[email protected]/dist/tailwind.min.css" rel="stylesheet">
	</head>
	<body class="bg-gray-100 text-gray-900">
	<form method="post" enctype="multipart/form-data" class="flex flex-col items-center p-4 bg-white shadow-md rounded-lg">
	<input type="file" name="image" accept="image/*" class="mb-4 p-2 border border-gray-300 rounded">
	<button type="submit" class="px-4 py-2 bg-blue-500 text-white rounded hover:bg-blue-700">Upload Image</button>
	</form>

	<?php

	$data = gzcompress($base64);

	?>

	<?php

	class HuffmanNode {
	public $char;
	public $freq;
	public $left;
	public $right;

	public function __construct($char, $freq, $left = null, $right = null) {
	$this->char = $char;
	$this->freq = $freq;
	$this->left = $left;
	$this->right = $right;
	}
	}

	// frequency count
	function calculateFrequency($text) {
	return array_count_values(str_split($text));
	}

	// Huffman Tree create
	function buildHuffmanTree($freq) {
	$heap = new SplPriorityQueue();

	foreach ($freq as $char => $f) {
	$heap->insert(new HuffmanNode($char, $f), -$f);
	}

	while ($heap->count() > 1) {
	$left = $heap->extract();
	$right = $heap->extract();
	$newNode = new HuffmanNode(null, $left->freq + $right->freq, $left, $right);
	$heap->insert($newNode, -$newNode->freq);
	}

	return $heap->extract();
	}

	// Huffman code generation
	function generateCodes($node, $prefix = "", &$codes = []) {
	if ($node == null) return;

	if ($node->char !== null) {
	$codes[$node->char] = $prefix;
	}

	generateCodes($node->left, $prefix . "0", $codes);
	generateCodes($node->right, $prefix . "1", $codes);
	}

	// encode
	function encode($text, $codes) {
	$encodedText = "";
	foreach (str_split($text) as $char) {
	$encodedText .= $codes[$char];
	}
	return $encodedText;
	}

	// decode
	function decode($encodedText, $tree) {
	$decodedText = "";
	$node = $tree;

	foreach (str_split($encodedText) as $bit) {
	$node = ($bit == '0') ? $node->left : $node->right;

	if ($node->char !== null) {
	$decodedText .= $node->char;
	$node = $tree;
	}
	}

	return $decodedText;
	}

	// test
	$text = $data;
	$freq = calculateFrequency($text);
	$tree = buildHuffmanTree($freq);
	$codes = [];
	generateCodes($tree, "", $codes);
	$encodedText = encode($text, $codes);
	$decodedText = decode($encodedText, $tree);


	// echo "Original Text: $text\n";
	// echo "Encoded Text: $encodedText\n";
	// echo "Decoded Text: $decodedText\n";



	?>

	<div class="flex flex-col items-center p-4 bg-white shadow-md rounded-lg">
	<div class="break-words">
	<?php echo $encodedText; ?>
	</div>
	</div>



	</body>
	</html>