diff --git a/tests/Utils/Image.alpha1.phpt b/tests/Utils/Image.alpha1.phpt
index 410526b88..f078d2533 100644
--- a/tests/Utils/Image.alpha1.phpt
+++ b/tests/Utils/Image.alpha1.phpt
@@ -25,10 +25,9 @@ $image2->place(Image::fromBlank(50, 50, Image::rgb(80, 174, 0)), 75, 25);
 
 Assert::same($image2->toString(Image::PNG, 0), $image->toString(Image::PNG, 0));
 
-ob_start();
-
 $image = Image::fromBlank(200, 100, Image::rgb(255, 128, 0, 60));
 $image->crop(0, 0, '60%', '60%');
-$image->send(Image::PNG, 0);
 
-Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha1.png'), ob_get_clean());
+ob_start();
+imagegd2($image->getImageResource());
+Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha1.gd2'), ob_get_clean());
diff --git a/tests/Utils/Image.alpha2.phpt b/tests/Utils/Image.alpha2.phpt
index 93ed353f5..a0fdacd8a 100644
--- a/tests/Utils/Image.alpha2.phpt
+++ b/tests/Utils/Image.alpha2.phpt
@@ -14,36 +14,44 @@ use Tester\Assert;
 require __DIR__ . '/../bootstrap.php';
 
 
+function toGd2($image)
+{
+	ob_start();
+	imagegd2($image->getImageResource());
+	return ob_get_clean();
+}
+
+
 $image = Image::fromFile(__DIR__ . '/fixtures.images/alpha1.png');
 $image->place(Image::fromFile(__DIR__ . '/fixtures.images/alpha2.png'), 0, 0, 100);
-Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.100.png'), $image->toString(Image::PNG, 0));
+Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.100.gd2'), toGd2($image));
 
 
 $image = Image::fromFile(__DIR__ . '/fixtures.images/alpha1.png');
 $image->place(Image::fromFile(__DIR__ . '/fixtures.images/alpha2.png'), 0, 0, 99);
-Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.99.png'), $image->toString(Image::PNG, 0));
+Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.99.gd2'), toGd2($image));
 
 
 $image = Image::fromFile(__DIR__ . '/fixtures.images/alpha1.png');
 $image->place(Image::fromFile(__DIR__ . '/fixtures.images/alpha2.png'), 0, 0, 50);
-Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.50.png'), $image->toString(Image::PNG, 0));
+Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.50.gd2'), toGd2($image));
 
 
 $image = Image::fromFile(__DIR__ . '/fixtures.images/alpha1.png');
 $image->place(Image::fromFile(__DIR__ . '/fixtures.images/alpha2.png'), 0, 0, 1);
-Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.1.png'), $image->toString(Image::PNG, 0));
+Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.1.gd2'), toGd2($image));
 
 
 $image = Image::fromFile(__DIR__ . '/fixtures.images/alpha1.png');
 $image->place(Image::fromFile(__DIR__ . '/fixtures.images/alpha2.png'), 0, 0, 0);
-Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.0.png'), $image->toString(Image::PNG, 0));
+Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.0.gd2'), toGd2($image));
 
 
 $image = Image::fromFile(__DIR__ . '/fixtures.images/alpha1.png');
 $image->place(Image::fromFile(__DIR__ . '/fixtures.images/alpha3.gif'), 0, 0, 100);
-Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.100b.png'), $image->toString(Image::PNG, 0));
+Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.100b.gd2'), toGd2($image));
 
 
 $image = Image::fromFile(__DIR__ . '/fixtures.images/alpha1.png');
 $image->place(Image::fromFile(__DIR__ . '/fixtures.images/alpha3.gif'), 0, 0, 50);
-Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.50b.png'), $image->toString(Image::PNG, 0));
+Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha2.50b.gd2'), toGd2($image));
diff --git a/tests/Utils/Image.drawing.phpt b/tests/Utils/Image.drawing.phpt
index fc4df619e..c236e44d6 100644
--- a/tests/Utils/Image.drawing.phpt
+++ b/tests/Utils/Image.drawing.phpt
@@ -14,6 +14,14 @@ use Tester\Assert;
 require __DIR__ . '/../bootstrap.php';
 
 
+function toGd2($image)
+{
+	ob_start();
+	imagegd2($image->getImageResource());
+	return ob_get_clean();
+}
+
+
 $size = 300;
 $image = Image::fromBlank($size, $size);
 
@@ -28,11 +36,11 @@ $image->filledEllipse(187, 125, $radius, $radius, Image::rgb(0, 0, 255, 75));
 
 $image->copyResampled($image, 200, 200, 0, 0, 80, 80, $size, $size);
 
-Assert::same(file_get_contents(__DIR__ . '/expected/Image.drawing.1.png'), $image->toString(Image::PNG, 0));
+Assert::same(file_get_contents(__DIR__ . '/expected/Image.drawing.1.gd2'), toGd2($image));
 
 
 // palette-based image
 $image = Image::fromFile(__DIR__ . '/fixtures.images/logo.gif');
 $image->filledEllipse(100, 50, 50, 50, Image::rgb(255, 255, 0, 75));
 $image->filledEllipse(100, 150, 50, 50, Image::rgb(255, 255, 0, 75));
-Assert::same(file_get_contents(__DIR__ . '/expected/Image.drawing.2.png'), $image->toString(Image::PNG, 0));
+Assert::same(file_get_contents(__DIR__ . '/expected/Image.drawing.2.gd2'), toGd2($image));
diff --git a/tests/Utils/Image.place.phpt b/tests/Utils/Image.place.phpt
index 4fec1a48a..0e849158d 100644
--- a/tests/Utils/Image.place.phpt
+++ b/tests/Utils/Image.place.phpt
@@ -20,7 +20,5 @@ $image = Image::fromBlank(100, 100, Image::rgb(0, 0, 0));
 $image->place($rectangle, '37.5%', '50%');
 
 ob_start();
-
-$image->send(Image::PNG, 0);
-
-Assert::same(file_get_contents(__DIR__ . '/expected/Image.place.png'), ob_get_clean());
+imagegd2($image->getImageResource());
+Assert::same(file_get_contents(__DIR__ . '/expected/Image.place.gd2'), ob_get_clean());
diff --git a/tests/Utils/Image.resize.phpt b/tests/Utils/Image.resize.phpt
index 6d11d4402..38f77c160 100644
--- a/tests/Utils/Image.resize.phpt
+++ b/tests/Utils/Image.resize.phpt
@@ -17,6 +17,14 @@ require __DIR__ . '/../bootstrap.php';
 $main = Image::fromFile(__DIR__ . '/fixtures.images/logo.gif');
 
 
+function toGd2($image)
+{
+	ob_start();
+	imagegd2($image->getImageResource());
+	return ob_get_clean();
+}
+
+
 test(function () use ($main) { // cropping...
 	$image = clone $main;
 	Assert::same(176, $image->width);
@@ -135,19 +143,19 @@ test(function () use ($main) { // rotate
 test(function () use ($main) { // alpha resize
 	$image = Image::fromFile(__DIR__ . '/fixtures.images/alpha1.png');
 	$image->resize(20, 20);
-	Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha.resize1.png'), $image->toString(Image::PNG, 0));
+	Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha.resize1.gd2'), toGd2($image));
 });
 
 
 test(function () use ($main) { // alpha flip
 	$image = Image::fromFile(__DIR__ . '/fixtures.images/alpha1.png');
 	$image->resize(-10, -10);
-	Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha.flip1.png'), $image->toString(Image::PNG, 0));
+	Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha.flip1.gd2'), toGd2($image));
 });
 
 
 test(function () use ($main) { // palette alpha resize
 	$image = Image::fromFile(__DIR__ . '/fixtures.images/alpha3.gif');
 	$image->resize(20, 20);
-	Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha.resize2.png'), $image->toString(Image::PNG, 0));
+	Assert::same(file_get_contents(__DIR__ . '/expected/Image.alpha.resize2.gd2'), toGd2($image));
 });
diff --git a/tests/Utils/expected/Image.alpha.flip1.gd2 b/tests/Utils/expected/Image.alpha.flip1.gd2
new file mode 100644
index 000000000..662774279
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diff --git a/tests/Utils/expected/Image.alpha.flip1.png b/tests/Utils/expected/Image.alpha.flip1.png
deleted file mode 100644
index 824489cbf..000000000
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diff --git a/tests/Utils/expected/Image.alpha.resize1.gd2 b/tests/Utils/expected/Image.alpha.resize1.gd2
new file mode 100644
index 000000000..13857719f
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diff --git a/tests/Utils/expected/Image.alpha.resize1.png b/tests/Utils/expected/Image.alpha.resize1.png
deleted file mode 100644
index 0528eb0c9..000000000
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diff --git a/tests/Utils/expected/Image.alpha.resize2.gd2 b/tests/Utils/expected/Image.alpha.resize2.gd2
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diff --git a/tests/Utils/expected/Image.alpha1.gd2 b/tests/Utils/expected/Image.alpha1.gd2
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diff --git a/tests/Utils/expected/Image.alpha2.0.gd2 b/tests/Utils/expected/Image.alpha2.0.gd2
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diff --git a/tests/Utils/expected/Image.alpha2.1.gd2 b/tests/Utils/expected/Image.alpha2.1.gd2
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