PHP version characterized image

I got interested after seeing this guy’s post. http://www.oschina.net/code/snippet_234517_15356

The image is magnified 10 times by default, so you can see it more clearly...

The OSC logo was used in the test. Let’s see how it works.
(The picture has been abbreviated, open this address in a new window to see the picture, 2000*560 http://img.it-home.org/data/attachment/forum/2014pic/11033136_K1mt.png)


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I tried PNG, GIF, and JPG, and they can all be characterized normally :)

$txt =array('A','B','C','D','E','F','G','H','I', 'J','K');
//Load the original image
$rawImage = ImageCreateFromGIF('logo.gif');
//Get the original image width and height
$rawImgWidth = ImagesX($rawImage);
$rawImgHeigh = ImagesY($rawImage);
//Get the original image grayscale
$grayData = getGrayData($rawImage,$rawImgWidth,$rawImgHeigh);
//Destroy the image
ImageDestroy($rawImage);
//Create text image
$ txtImage = ImageCreate($rawImgWidth*6,$rawImgHeigh*9);
//New image background color
imagecolorallocate($txtImage,0,0,0);
//Get the maximum grayscale
for($i=0; $i $maxGrayArray[$i] = max($grayData[$i]);
}
$maxGray = max($maxGrayArray);
//Set grayscale correspondence Color
for($i=0;$i<$maxGray+1;$i++){
 $color = 255-round(200/$maxGray)*$i+55;
 $gray[$i] = imagecolorallocate( $txtImage,$color,$color,$color);
}
//Draw characters
for($y=0;$y<$rawImgHeigh;$y++){
 for($x=0;$x<$ rawImgWidth;$x++){
 Imagechar($txtImage,1,$x*6,$y*9,$txt[rand(0,10)],$gray[$grayData[$x][$y]]) ;
 }
}
//Create the final image
$Image = ImageCreate($rawImgWidth*10,$rawImgHeigh*10);
//Stretch the image
imagecopyresampled($Image, $txtImage, 0, 0, 0, 0 ,$rawImgWidth*10,$rawImgHeigh*10,$rawImgWidth*6,$rawImgHeigh*9);
//Define file header
header('Content-type: image/png');
//Output image
ImagePNG( $Image);
//Destroy the image
ImageDestroy($Image);

/*
 Get the gray value
*/
function getGrayData($mImage,$mImgWidth,$mImgHeigh){
 for($mY=0; $mY<$mImgHeigh;$mY++){
 for($mX=0;$mX<$mImgWidth;$mX++){
 $mRGB = Imagecolorat($mImage, $mX, $mY);
 $mR = ($ mRGB >> 16) & 0xFF;
 $mG = ($mRGB >> 8) & 0xFF;
 $mB = $mRGB & 0xFF;;
 $mGrayData[$mX][$mY] = ($ mR * 19595 + $mG * 38469 + $mB * 7472) >> 16;
 }
 }
 return $mGrayData;
}
?>