hasTransparency()

Complexity

Conditions	31
Paths	99

Size

Total Lines	109
Code Lines	52

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	0
CRAP Score	992

Importance

Changes	2
Bugs	0	Features	0

<?php
function hasTransparency($fileName, $png = true)
{
	if (empty($fileName) || !file_exists($fileName))
		return false;

	$header = file_get_contents($fileName, false, null, 0, 26);

	// Does it even claim to have been saved with transparency
	if ($png && !ord($header[25]) & 4)
		return false;

	// Webp has its own
	if (!$png)
	{
		if (($header[15] === 'L' && !(ord($header[24]) & 16)) || ($header[15] === 'X' && !(ord($header[20]) & 16)))
		{
			return false;
		}
	}

	// Saved with transparency is only a start, now Pixel inspection
	$webp_support = hasWebpSupport(true);
	if (checkImagick() && ($png || $webp_support === 'im'))
	{
		$transparency = false;
		try
		{
			$image = new Imagick($fileName);
			if ($image->getImageWidth() > 1024 || $image->getImageHeight() > 1024)
			{
				// Used to look for transparency, it is not intended to be a quality image.
				$scaleValue = getImageScaleFactor($image->getImageWidth(), $image->getImageHeight());
				$image->scaleImage($scaleValue[0], $scaleValue[1], true);
			}

			$pixel_iterator = $image->getPixelIterator();

			// Look at each one, or until we find the first alpha pixel
			foreach ($pixel_iterator as $pixels)
			{
				foreach ($pixels as $pixel)
				{
					$color = $pixel->getColor();
					if ($color['a'] < 1)
					{
						$transparency = true;
						break 2;
					}
				}
			}
		}
		catch (\ImagickException $e)
		{
			// We don't know what it is, so don't mess with it
			unset($image);
			return true;
		}

		unset($image);

		return $transparency;
	}

	if (checkGD() && ($png || $webp_support === 'gd'))
	{
		// Go through the image pixel by pixel until we find a transparent pixel
		$transparency = false;
		list ($width, $height, $type) = elk_getimagesize($fileName);

		if ($type === 18 && $webp_support === 'gd')

The condition $webp_support === 'gd' is always false.

			$image = imagecreatefromwebp($fileName);
		elseif ($type === 3)
			$image = imagecreatefrompng($fileName);
		else
			return false;

		// Large image, scale down to reduce processing time
		if ($width > 1024 || $height > 1024)
		{
			// Single pass scale down, not looking for quality here
			$scaleValue = getImageScaleFactor($width, $height);
			$image = imagescale($image, $scaleValue[0], $scaleValue[1], IMG_NEAREST_NEIGHBOUR);
			if (!$image)
			{
				return true;
			}
		}

		$x = imagesx($image);
		$y = imagesy($image);
		for ($i = 0; $i < $x; $i++)
		{
			for ($j = 0; $j < $y; $j++)
			{
				if (imagecolorat($image, $i, $j) & 0x7F000000)
				{
					$transparency = true;
					break 2;
				}
			}
		}

		unset($image);

		return $transparency;
	}

	// Don't know so assume true
	return true;
}