summaryrefslogtreecommitdiffstats
path: root/application/libraries/Imglib.php
diff options
context:
space:
mode:
authorFlorian Pritz <bluewind@xinu.at>2014-09-29 00:41:35 +0200
committerFlorian Pritz <bluewind@xinu.at>2014-10-03 14:22:34 +0200
commit9b0b9a0e6082b3375ebdadc651c971671c922ebc (patch)
tree952f529eb974af6091a6f401b6aca012ddc4005d /application/libraries/Imglib.php
parent64628978d76c19e946754acc922144aff739b83d (diff)
Move thumbnail code to dedicated class
This also moves the code from mfile->image_dimension() to the only place where it was called. Signed-off-by: Florian Pritz <bluewind@xinu.at>
Diffstat (limited to 'application/libraries/Imglib.php')
-rw-r--r--application/libraries/Imglib.php169
1 files changed, 169 insertions, 0 deletions
diff --git a/application/libraries/Imglib.php b/application/libraries/Imglib.php
new file mode 100644
index 000000000..4d6de21d3
--- /dev/null
+++ b/application/libraries/Imglib.php
@@ -0,0 +1,169 @@
+<?php
+/*
+ * Copyright 2014 Florian "Bluewind" Pritz <bluewind@server-speed.net>
+ *
+ * Licensed under AGPLv3
+ * (see COPYING for full license text)
+ *
+ */
+
+class Imglib {
+ /*
+ * This returns a square thumbnail for the input image
+ * Source: http://salman-w.blogspot.co.at/2009/04/crop-to-fit-image-using-aspphp.html
+ */
+ public function makeThumb($file, $size = 150, $target_type = null)
+ {
+ $source_gdim = imagecreatefromstring(file_get_contents($file));
+ if ($source_gdim === false) {
+ show_error("Unsupported image type");
+ }
+ imagealphablending($source_gdim,false);
+ imagesavealpha($source_gdim,true);
+
+ list($source_width, $source_height, $source_type) = getimagesize($file);
+
+ if ($target_type === null) {
+ $target_type = $source_type;
+ }
+
+ $target_width = $size;
+ $target_height = $size;
+
+ $source_aspect_ratio = $source_width / $source_height;
+ $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));
+ }
+
+ /*
+ * Resize the image into a temporary GD image
+ */
+
+ $temp_gdim = imagecreatetruecolor($temp_width, $temp_height);
+ imagealphablending($temp_gdim,false);
+ imagesavealpha($temp_gdim,true);
+ imagecopyresampled(
+ $temp_gdim,
+ $source_gdim,
+ 0, 0,
+ 0, 0,
+ $temp_width, $temp_height,
+ $source_width, $source_height
+ );
+
+ /*
+ * Copy cropped region from temporary image into the desired GD image
+ */
+
+ $x0 = ($temp_width - $target_width) / 2;
+ $y0 = ($temp_height - $target_height) / 2;
+ $thumb = imagecreatetruecolor($target_width, $target_height);
+ imagealphablending($thumb,false);
+ imagesavealpha($thumb,true);
+ imagecopy(
+ $thumb,
+ $temp_gdim,
+ 0, 0,
+ $x0, $y0,
+ $target_width, $target_height
+ );
+
+ /*
+ * Fix orientation according to exif tag
+ */
+ try {
+ $exif = exif_read_data($file);
+ } catch (ErrorException $e) {
+ }
+
+ if (isset($exif['Orientation'])) {
+ $mirror = false;
+ $deg = 0;
+
+ switch ($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) $thumb = imagerotate($thumb, $deg, 0);
+ if ($mirror) $thumb = $this->_mirrorImage($thumb);
+ }
+
+ ob_start();
+ switch ($target_type) {
+ case IMAGETYPE_GIF:
+ $ret = imagegif($thumb);
+ break;
+ case IMAGETYPE_JPEG:
+ $ret = imagejpeg($thumb);
+ break;
+ case IMAGETYPE_PNG:
+ $ret = imagepng($thumb);
+ break;
+ default:
+ assert(0);
+ }
+ $result = ob_get_clean();
+
+ if (!$ret) {
+ show_error("Failed to create thumbnail");
+ }
+
+ imagedestroy($thumb);
+ imagedestroy($temp_gdim);
+ imagedestroy($source_gdim);
+
+ return $result;
+ }
+
+ private function _mirrorImage($imgsrc)
+ {
+ $width = imagesx($imgsrc);
+ $height = imagesy($imgsrc);
+
+ $src_x = $width -1;
+ $src_y = 0;
+ $src_width = -$width;
+ $src_height = $height;
+
+ $imgdest = imagecreatetruecolor($width, $height);
+ imagealphablending($imgdest,false);
+ imagesavealpha($imgdest,true);
+
+ if (imagecopyresampled($imgdest, $imgsrc, 0, 0, $src_x, $src_y, $width, $height, $src_width, $src_height)) {
+ return $imgdest;
+ }
+
+ return $imgsrc;
+ }
+
+}