Add imagemagick support

Adds additional support for imagemagick if GD doesn't support a file
type and extends the files displayed as thumbnails to all images and
pdf files.

Signed-off-by: Florian Pritz <bluewind@xinu.at>

1 files changed, 226 insertions, 0 deletions

diff --git a/application/libraries/Image/Drivers/GD.php b/application/libraries/Image/Drivers/GD.php
new file mode 100644
index 000000000..5c6411ced
--- /dev/null
+++ b/application/libraries/Image/Drivers/GD.php
@@ -0,0 +1,226 @@
+<?php
+/*
+ * Copyright 2014-2015 Florian "Bluewind" Pritz <bluewind@server-speed.net>
+ *
+ * Licensed under AGPLv3
+ * (see COPYING for full license text)
+ *
+ */
+
+namespace libraries\Image\Drivers;
+
+class GD implements \libraries\Image\ImageDriver {
+	private $img;
+	private $source_type;
+	private $exif;
+
+	public static function get_priority($mimetype)
+	{
+		switch($mimetype) {
+		case "image/jpeg":
+		case "image/png":
+		case "image/gif":
+			return 1000;
+			break;
+		default:
+			return -1;
+			break;
+		}
+	}
+
+	/**
+	 * Create a new object and load the contents of file.
+	 * @param file file to read
+	 */
+	public function __construct($file)
+	{
+		$this->read($file);
+	}
+
+	public function read($file)
+	{
+		$img = imagecreatefromstring(file_get_contents($file));
+		if ($img === false) {
+			throw new \exceptions\ApiException("libraries/Image/unsupported-image-type", "Unsupported image type");
+		}
+		$this->set_img_object($img);
+		$this->fix_alpha();
+
+		$this->source_type = getimagesize($file)[2];
+		$this->exif = \libraries\Exif::get_exif($file);
+	}
+
+	public function get($target_type = null)
+	{
+		if ($target_type === null) {
+			$target_type = $this->source_type;
+		}
+
+		ob_start();
+		switch ($target_type) {
+			case IMAGETYPE_GIF:
+				$ret = imagegif($this->img);
+				break;
+			case IMAGETYPE_JPEG:
+				$ret = imagejpeg($this->img);
+				break;
+			case IMAGETYPE_PNG:
+				$ret = imagepng($this->img);
+				break;
+			default:
+				assert(0);
+		}
+		$result = ob_get_clean();
+
+		if (!$ret || $result === false) {
+			throw new \exceptions\ApiException("libraries/Image/thumbnail-creation-failed", "Failed to create thumbnail");
+		}
+
+		return $result;
+	}
+
+	public function resize($width, $height)
+	{
+		$temp_gdim = imagecreatetruecolor($width, $height);
+		$this->fix_alpha();
+		imagecopyresampled(
+			$temp_gdim,
+			$this->img,
+			0, 0,
+			0, 0,
+			$width, $height,
+			imagesx($this->img), imagesy($this->img)
+		);
+
+		$this->set_img_object($temp_gdim);
+	}
+
+	public function crop($x, $y, $width, $height)
+	{
+		$thumb = imagecreatetruecolor($width, $height);
+		$this->fix_alpha();
+		imagecopy(
+			$thumb,
+			$this->img,
+			0, 0,
+			$x, $y,
+			$width, $height
+		);
+
+		$this->set_img_object($thumb);
+	}
+
+	// Source: http://salman-w.blogspot.co.at/2009/04/crop-to-fit-image-using-aspphp.html
+	public function makeThumb($target_width, $target_height)
+	{
+		$source_aspect_ratio = imagesx($this->img) / imagesy($this->img);
+		$desired_aspect_ratio = $target_width / $target_height;
+
+		if ($source_aspect_ratio > $desired_aspect_ratio) {
+			// Triggered when source image is wider
+			$temp_height = $target_height;
+			$temp_width = round(($target_height * $source_aspect_ratio));
+		} else {
+			// Triggered otherwise (i.e. source image is similar or taller)
+			$temp_width = $target_width;
+			$temp_height = round(($target_width / $source_aspect_ratio));
+		}
+
+		$this->resize($temp_width, $temp_height);
+
+		$x0 = ($temp_width - $target_width) / 2;
+		$y0 = ($temp_height - $target_height) / 2;
+		$this->crop($x0, $y0, $target_width, $target_height);
+
+		$this->apply_exif_orientation();
+	}
+
+	static public function get_exif_orientation($file)
+	{
+		$exif = \libraries\Exif::get_exif($file);
+		if (isset($exif["Orientation"])) {
+			return $exif["Orientation"];
+		}
+		return 0;
+	}
+
+	public function apply_exif_orientation()
+	{
+		if (isset($this->exif['Orientation'])) {
+			$mirror = false;
+			$deg    = 0;
+
+			switch ($this->exif['Orientation']) {
+			case 2:
+				$mirror = true;
+				break;
+			case 3:
+				$deg = 180;
+				break;
+			case 4:
+				$deg = 180;
+				$mirror = true;
+				break;
+			case 5:
+				$deg = 270;
+				$mirror = true;
+				break;
+			case 6:
+				$deg = 270;
+				break;
+			case 7:
+				$deg = 90;
+				$mirror = true;
+				break;
+			case 8:
+				$deg = 90;
+				break;
+			}
+
+			if ($deg) {
+				$this->set_img_object(imagerotate($this->img, $deg, 0));
+			}
+
+			if ($mirror) {
+				$this->mirror();
+			}
+		}
+	}
+
+	public function mirror()
+	{
+		$width = imagesx($this->img);
+		$height = imagesy($this->img);
+
+		$src_x = $width -1;
+		$src_y = 0;
+		$src_width = -$width;
+		$src_height = $height;
+
+		$imgdest = imagecreatetruecolor($width, $height);
+		imagealphablending($imgdest,false);
+		imagesavealpha($imgdest,true);
+
+		imagecopyresampled($imgdest, $this->img, 0, 0, $src_x, $src_y, $width, $height, $src_width, $src_height);
+		$this->set_img_object($imgdest);
+	}
+
+	private function set_img_object($new)
+	{
+		assert($new !== false);
+
+		$old = $this->img;
+		$this->img = $new;
+
+		if ($old != null) {
+			imagedestroy($old);
+		}
+	}
+
+	private function fix_alpha()
+	{
+		imagealphablending($this->img,false);
+		imagesavealpha($this->img,true);
+	}
+
+}