Created
July 28, 2012 18:24
-
-
Save RickyRomero/3194304 to your computer and use it in GitHub Desktop.
Creates and verifies full 16,777,216-color PNGs.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
<?php | |
ini_set("memory_limit", "256M"); | |
if (isset($argv[1])) | |
{ | |
echo "Verifying image...\n"; | |
verify16777216($argv[1]); | |
} | |
else | |
{ | |
echo "No path set. Creating image...\n"; | |
create16777216(); | |
} | |
function pixelToRGB($x, $y, $w) | |
{ | |
$pixelNum = ($y * $w) + $x; | |
$r = (int)($pixelNum % 256); | |
$g = (int)(floor($pixelNum / 256) % 256); | |
$b = (int)(floor($pixelNum / (256 * 256))); | |
return array($r, $g, $b); | |
} | |
function create16777216() | |
{ | |
$size = 4096; | |
$img = imagecreatetruecolor($size, $size); | |
for ($i = 0; $i < $size * $size; $i++) | |
{ | |
$x = $i % $size; | |
$y = floor($i / $size); | |
$rgb = pixelToRGB($x, $y, $size); | |
$color = imagecolorallocate($img, $rgb[0], $rgb[1], $rgb[2]); | |
imagesetpixel($img, $x, $y, $color); | |
} | |
echo "Saving 16777216.png to current directory...\n"; | |
imagepng($img, "16777216.png", 0); | |
} | |
function verify16777216($file) | |
{ | |
$size = 4096; | |
$img = imagecreatefrompng($file); | |
for ($i = 0; $i < $size * $size; $i++) | |
{ | |
$x = $i % $size; | |
$y = floor($i / $size); | |
$theirRGB = imagecolorat($img, $x, $y); | |
$theirR = ($theirRGB >> 16) & 0xFF; | |
$theirG = ($theirRGB >> 8) & 0xFF; | |
$theirB = $theirRGB & 0xFF; | |
$ourRGB = pixelToRGB($x, $y, $size); | |
if ($theirR !== $ourRGB[0] || $theirG !== $ourRGB[1] || $theirB !== $ourRGB[2]) | |
{ | |
die( | |
"Images differ at x:" . $x . " y:" . $y . ".\n" . | |
"Us: r:" . $ourRGB[0] . " g:" . $ourRGB[1] . " b:" . $ourRGB[2] . "\n" . | |
"Them: r:" . $theirR . " g:" . $theirG . " b:" . $theirB . "\n" | |
); | |
} | |
} | |
exit("The images are identical.\n"); | |
} | |
?> |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment