Changeset 7868

Timestamp:

Nov 24, 2010, 1:45:16 PM (14 years ago)

Author:

plg

Message:

feature 2040 added: automatic rotation of the photo based on EXIF Orientation.

The code could have been shorter but this one 1) checks the resize dimension
with the rotation in mind 2) rotates the photo once resized to reduce memory
used.

File:

• trunk/admin/include/functions_upload.inc.php (modified) (6 diffs)

trunk/admin/include/functions_upload.inc.php

@@ -184 +184 @@
 function need_resize($image_filepath, $max_width, $max_height)
 {
+  // TODO : the resize check should take the orientation into account. If a
+  // rotation must be applied to the resized photo, then we should test
+  // invert width and height.
   list($width, $height) = getimagesize($image_filepath);
   
@@ -192 +195 @@
 
   return false;
+}
+
+function get_resize_dimensions($width, $height, $max_width, $max_height, $rotation=null)
+{
+  $rotate_for_dimensions = false;
+  if (isset($rotation) and in_array(abs($rotation), array(90, 270)))
+  {
+    $rotate_for_dimensions = true;
+  }
+
+  if ($rotate_for_dimensions)
+  {
+    list($width, $height) = array($height, $width);
+  }
+  
+  $ratio_width  = $width / $max_width;
+  $ratio_height = $height / $max_height;
+  
+  // maximal size exceeded ?
+  if ($ratio_width > 1 or $ratio_height > 1)
+  {
+    if ($ratio_width < $ratio_height)
+    { 
+      $destination_width = ceil($width / $ratio_height);
+      $destination_height = $max_height;
+    }
+    else
+    { 
+      $destination_width = $max_width; 
+      $destination_height = ceil($height / $ratio_width);
+    }
+  }
+
+  if ($rotate_for_dimensions)
+  {
+    list($destination_width, $destination_height) = array($destination_height, $destination_width);
+  }
+  
+  return array(
+    'width' => $destination_width,
+    'height'=> $destination_height,
+    );
 }
 
@@ -222 +267 @@
   {
     die('unsupported file extension');
+  }
+
+  $rotation = null;
+  if (function_exists('imagerotate'))
+  {
+    $exif = exif_read_data($source_filepath);
+    if (isset($exif['Orientation']) and preg_match('/^\s*(\d)/', $exif['Orientation'], $matches))
+    {
+      $orientation = $matches[1];
+      if (in_array($orientation, array(3, 4)))
+      {
+        $rotation = 180;
+      }
+      elseif (in_array($orientation, array(5, 6)))
+      {
+        $rotation = 270;
+      }
+      elseif (in_array($orientation, array(7, 8)))
+      {
+        $rotation = 90;
+      }
+    }
   }
   
@@ -228 +295 @@
   $source_height = imagesy($source_image);
   
-  $ratio_width  = $source_width / $max_width;
-  $ratio_height = $source_height / $max_height;
-  
-  // maximal size exceeded ?
-  if ($ratio_width > 1 or $ratio_height > 1)
-  {
-    if ($ratio_width < $ratio_height)
-    { 
-      $destination_width = ceil($source_width / $ratio_height);
-      $destination_height = $max_height; 
-    }
-    else
-    { 
-      $destination_width = $max_width; 
-      $destination_height = ceil($source_height / $ratio_width);
-    }
-  }
-  else
+  $resize_dimensions = get_resize_dimensions($source_width, $source_height, $max_width, $max_height, $rotation);
+
+  // testing on height is useless in theory: if width is unchanged, there
+  // should be no resize, because width/height ratio is not modified.
+  if ($resize_dimensions['width'] == $source_width and $resize_dimensions['height'] == $source_height)
   {
     // the image doesn't need any resize! We just copy it to the destination
@@ -252 +306 @@
   }
   
-  $destination_image = imagecreatetruecolor($destination_width, $destination_height);
+  $destination_image = imagecreatetruecolor($resize_dimensions['width'], $resize_dimensions['height']);
   
   imagecopyresampled(
@@ -261 +315 @@
     0,
     0,
-    $destination_width,
-    $destination_height,
+    $resize_dimensions['width'],
+    $resize_dimensions['height'],
     $source_width,
     $source_height
     );
+
+  // rotation occurs only on resized photo to avoid useless memory use
+  if (isset($rotation))
+  {
+    $destination_image = imagerotate($destination_image, $rotation, 0);
+  }
   
   $extension = strtolower(get_extension($destination_filepath));