Crosstitch converter

stitch.php

<?php
// Take an image and convert it into a crosstitch grid

function textImage($msg = "No message") {
	$char_size = 3;		# Which standard font size?
	$char_height = 35;	# How tall is a line?
	$char_width = 7;	# How wide is each character?
	
	// Determine width based on string length
	$width = strlen($msg)*$char_width+30;
	
	// Create a blank image to draw on
	$im = @imagecreatetruecolor($width, $char_height) or die("Cannot Initialize new GD image stream");
	$bg = imagecolorallocate($im, 250, 230, 230);
	imagefill($im, 0, 0, $bg);
	$text_color = imagecolorallocate($im, 233, 14, 91);
	
	// Write messgae
	imagestring($im, 3, 15, 10,  $msg, $text_color);

	// Export the final image
	header ("Content-type: image/png");
	imagepng($im);
	imagedestroy($im);
}

function showImage($im) {
	# Export the final image
	header ("Content-type: image/png");
	imagepng($im);
	imagedestroy($im);
	exit;
}

if (!isset($_REQUEST['img']) && $_REQUEST['img'] == "") {
	textImage("Must pass an 'img' value");
	exit;
}
$source_file = $_GET['img']; // The filename of the source file.
if (isset($_GET['mask']) && $_GET['mask'] != "") {
	$do_mask = TRUE;
	$masked = explode(",", $_GET['mask']); // Show only a few colors?
} else {
	$do_mask = FALSE;
}
$source = imagecreatefromgif($source_file);
if (!$source) {
	// Failed to load
	textImage("Failed to load source; make sure it is a GIF image.");
	exit;
}
list($w_px, $h_px, $tmp) = getimagesize($source_file);

// The symbols are all 7x7px in dimension. With a 1px gridline between all cells, and a 3 pixel gridline between every tenth cell, each group of ten cells is 82 pixels wide. i.e.:
// -------|-------|-------|-------|-------|-------|-------|-------|-------|-------|||

$w_sets = floor($w_px/10);
$w_grid = $w_sets*82 + ($w_px-($w_sets*10))*8+1;
$h_sets = floor($h_px/10);
$h_grid = $h_sets*82 + ($h_px-($h_sets*10))*8;

//textImage("Source is $w_px x $h_px px, final will be $w_grid x $h_grid px.");
// Determine the number of colors of the final image
if ($do_mask) $mask = imagecreatefromgif("images/mask.gif");
$symbols = array("-1" => array("color" => "-1", "img" => $mask));
for ($x=0; $x<=$w_px; $x++) {
	for ($y=0; $y<=$h_px; $y++) {
		$rgb = imagecolorat($source, $x, $y);
		$cdata = imagecolorsforindex($source, $rgb);
		if ($cdata['alpha'] == 0) {
			$symbol = findsymbol($rgb);
		}
	}
}
// Now all colors should be loaded into $symbols.
$color_count = count($symbols)-1;
$legend_w = 150; // How much space to allocate per color definition
$legend_h = 20;
$per_row = floor($w_grid/$legend_w);
$rows = ceil($color_count/$per_row);
$tot_h = $h_grid + 10 + $rows*$legend_h; // Add on to the bottom of the image the required space

$im = imagecreatetruecolor($w_grid, $tot_h); // New image for holding grid image
$white = imagecolorallocate($im, 255, 255, 255); 
$black = imagecolorallocate($im, 0, 0, 0);
$gray = imagecolorallocate($im, 180, 180, 180);
imagefill($im, 2, 2, $white); // Make a white background

// Draw the grids
$x = 0;
$col = 0;
while ($x <= $w_grid) {
	if ($col < 10) {
		// Draw a thin line
		imageline ($im, $x, 0, $x, $h_grid, $gray);
		$col++;
		$x += 8;
	} else {
		// Draw a thick line
		imageline ($im, $x, 0, $x, $h_grid, $black);
		imageline ($im, $x+1, 0, $x+1, $h_grid, $black);
		imageline ($im, $x+2, 0, $x+2, $h_grid, $black);
		$col = 1;
		$x += 10;
	}
}
$y = 0;
$row = 0;
while ($y <= $h_grid) {
	if ($row < 10) {
		// Draw a thin line
		imageline ($im, 0, $y, $w_grid, $y, $gray);
		$row++;
		$y += 8;
	} else {
		// Draw a thick line
		imageline ($im, 0, $y, $w_grid, $y, $black);
		imageline ($im, 0, $y+1, $w_grid, $y+1, $black);
		imageline ($im, 0, $y+2, $w_grid, $y+2, $black);
		$row = 1;
		$y += 10;
	}
}
// Re-do the vertical thick lines, since they got painted over
$x = 80;
while ($x <= $w_grid) {
	// Draw a thick line
	imageline ($im, $x, 0, $x, $h_grid, $black);
	imageline ($im, $x+1, 0, $x+1, $h_grid, $black);
	imageline ($im, $x+2, 0, $x+2, $h_grid, $black);
	$x += 82;
}


// Now go through and grab the colors from the source
for($x = 0; $x<= $w_px; $x++) {
	for ($y = 0; $y< $h_px; $y++) {
		// What is the color at this pixel of the source image
		$rgb = imagecolorat($source, $x, $y);
		$cdata = imagecolorsforindex($source, $rgb);
		if ($cdata['alpha'] == 0) {
			$symbol = findsymbol($rgb);
			$dstx_tens = floor($x/10);
			$dsty_tens = floor($y/10);
			$dst_x = $dstx_tens*82 + ($x-$dstx_tens*10)*8+1;
			$dst_y = $dsty_tens*82 + ($y-$dsty_tens*10)*8+1;
			imagecopy($im, $symbol, $dst_x, $dst_y, 0, 0, 7, 7);
		}
	}
}

// Finally, show the legend on the bottom of the image.
$col = 0;
$row = 1;
for($x=1; $x<count($symbols); $x++) {
	$color = $symbols[$x];
	$dst_x = $col*$legend_w+10;
	$dst_y = $h_grid + ($row-1)*$legend_h + 6;
	// Show the symbol for this color
	imagecopy($im, $color['img'], $dst_x, $dst_y, 0, 0, 7, 7);
	imagerectangle($im, $dst_x-1, $dst_y-1, $dst_x+7, $dst_y+7, $gray);
	// Draw the label after the symbol
	$str = ": (#".$color['color'].") #".$color['str'];
	imagestring($im, 2, $dst_x+10, $dst_y-4, $str, $black);
	$col++;
	if ($col >= $per_row) {
		$col = 0;
		$row++;
	}
}

showImage($im);		

function findsymbol($index) {
	global $source;
	global $symbols;
	global $masked;
	global $do_mask;
	if ($index == "") { $index = 0; }
	if ($do_mask == TRUE) {
		// First check and see if this color is masked 
		if (!in_array($index, $masked)) {
			// Not on the chosen list; show the mask image instead
			return $symbols[-1]['img'];
		}
	}
	foreach($symbols as $symbol) {
		if ($symbol['color'] == $index) {
			// Found the match
			return $symbol['img'];
		}
	}
	// If we get here, we haven't found a match. Therefore, this is a new color, make a symbol for it.
	$next = count($symbols); // What's the next symbol?
	$next_img = imagecreatefromgif("images/s".$next.".gif");
	// Go through and replace colors
	$color = imagecolorsforindex($source, $index);
	$white = imagecolorallocate($next_img, $color['red'], $color['green'], $color['blue']);
	//$black = imagecolorallocate($next_img, 255-$color['red'], 255-$color['green'], 255-$color['blue']);
	if (($color['red']+$color['green']+$color['blue'])/3 < 100) {
		$black = imagecolorallocate($next_img, 255, 255, 255);
	} else {
		$black = imagecolorallocate($next_img, 0, 0, 0);
	}
	for($x=0; $x<imagesx($next_img); $x++) {
		for($y=0; $y<imagesy($next_img); $y++) {
			$cur_color = imagecolorsforindex($next_img, imagecolorat($next_img, $x, $y));
			if ($cur_color['red'] > 200 && $cur_color['green'] > 200 && $cur_color['blue'] > 200) {
				imagesetpixel($next_img, $x, $y, $white);
			} else {
				imagesetpixel($next_img, $x, $y, $black);
			}
		}
	}
	$color_str = strtoupper(sprintf("%02s", dechex($color['red'])).sprintf("%02s", dechex($color['green'])).sprintf("%02s", dechex($color['blue'])));
	$symbols[$next] = array("color" => $index, "img" => $next_img, "str" => $color_str);
	return $next_img;
}