function SmartcropTestCase::difference in Smart Crop 7

Same name and namespace in other branches

1. 6 tests/smartcrop.test \SmartcropTestCase::difference()

Calculate the difference of 2 images.

Parameters

$image1 A GD image resource.:

$image2 A GD image resource.:

Return value

A GD image resource, with the subtracted image.

2 calls to SmartcropTestCase::difference()

SmartcropTestCase::assertImageEqual in tests/smartcrop.test

Assert that two images are the same, with some difference allowed to account for e.g. compression artifacts.

SmartcropTestCase::assertImageNotEqual in tests/smartcrop.test

Assert that two images are not the same, with some difference allowed to account for e.g. compression artifacts.

File

tests/smartcrop.test, line 231

Tests for the smartcrop module.

Class

SmartcropTestCase

@file Tests for the smartcrop module.

Code

function difference($image1, $image2) {
  $this
    ->assertEqual(imagesx($image1), imagesx($image2), t('Images have the same width.'));
  $this
    ->assertEqual(imagesy($image1), imagesy($image2), t('Images have the same height.'));
  $difference = imagecreatetruecolor(imagesx($image1), imagesy($image1));
  for ($i = 0; $i < imagesx($image1); $i++) {
    for ($j = 0; $j < imagesy($image1); $j++) {
      $rgb1 = imagecolorat($image1, $i, $j);
      $r1 = $rgb1 >> 16 & 0xff;
      $g1 = $rgb1 >> 8 & 0xff;
      $b1 = $rgb1 & 0xff;
      $rgb2 = imagecolorat($image2, $i, $j);
      $r2 = $rgb2 >> 16 & 0xff;
      $g2 = $rgb2 >> 8 & 0xff;
      $b2 = $rgb2 & 0xff;
      imagesetpixel($difference, $i, $j, imagecolorallocate($difference, abs($r2 - $r1), abs($g2 - $g1), abs($b2 - $b1)));
    }
  }
  return $difference;
}