diff --git a/.gitignore b/.gitignore
index bfa5383..5812d06 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,5 +4,6 @@
 composer.lock
 phpDocumentor.phar
 
+build/
 public/
 vendor/
\ No newline at end of file
diff --git a/docs/changes/0.1.2.md b/docs/changes/0.1.2.md
new file mode 100644
index 0000000..6009c4e
--- /dev/null
+++ b/docs/changes/0.1.2.md
@@ -0,0 +1,14 @@
+# 0.1.2
+
+## Enhancements
+
+- WMF\Reader\WMF\Magic : Backends sorted by priority in [#6](https://github.com/PHPOffice/WMF/pull/6) by [@Progi1984](https://github/Progi1984)
+
+## Bug fixes
+
+- N/A
+
+## Miscellaneous
+
+- N/A
+ 
\ No newline at end of file
diff --git a/docs/usage/wmf.md b/docs/usage/wmf.md
index 69d80d1..73687da 100644
--- a/docs/usage/wmf.md
+++ b/docs/usage/wmf.md
@@ -7,6 +7,9 @@ You can load `.wmf` files.
 You can one of two current backends : `gd` or `imagick`.
 If you don't know which one used, you can use the magic one.
 
+By default, the order of the backends is Imagick, followed by GD.
+Each backend is tested on different criteria: extension loaded, format support.
+
 ```php
 <?php
 
@@ -22,7 +25,41 @@ $reader = new Magic();
 $reader->load('sample.wmf');
 ```
 
-For next sample, I will use the magic one.
+For next samples, I will use the magic one.
+
+### `getBackends`
+
+This specific method for `Magic::class` returns backends sorted by priority.
+
+```php
+<?php
+
+use PhpOffice\WMF\Reader\WMF\Magic;
+
+$reader = new Magic();
+
+var_dump($reader->getBackends());
+```
+
+### `setBackends`
+
+This specific method for `Magic::class` defines backends sorted by priority.
+
+```php
+<?php
+
+use PhpOffice\WMF\Reader\WMF\GD;
+use PhpOffice\WMF\Reader\WMF\Imagick;
+use PhpOffice\WMF\Reader\WMF\Magic;
+
+$reader = new Magic();
+$reader->setBackends([
+  GD::class,
+  Imagick::class,
+]);
+
+var_dump($reader->getBackends());
+```
 
 ## Methods
 
@@ -39,15 +76,14 @@ The `Imagick` backend returns a `Imagick` object.
 use PhpOffice\WMF\Reader\WMF\Magic;
 
 $reader = new Magic();
+$reader->load('sample.wmf');
 
-$wmf = $reader->load('sample.wmf');
-
-var_dump($wmf->getResource());
+var_dump($reader->getResource());
 ```
 
 ### `getMediaType`
 
-The method returns the media type for a WMF file
+The method returns the media type for a WMF file.
 
 ```php
 <?php
@@ -63,7 +99,7 @@ echo 'The media type for a WMF file is ' . $$mediaType;
 
 ### `isWMF`
 
-The method allows to know if the file is supported by the library.
+The method returns if the file is supported by the library.
 
 ```php
 <?php
@@ -71,15 +107,17 @@ The method allows to know if the file is supported by the library.
 use PhpOffice\WMF\Reader\WMF\Magic;
 
 $reader = new Magic();
+$reader->load('sample.wmf');
 
-$isWMF = $reader->isWMF('sample.wmf');
+$isWMF = $reader->isWMF();
 
 echo 'The file sample.wmf ' . ($isWMF ? 'is a WMF file' : 'is not a WMF file');
 ```
 
 ### `load`
 
-The method load a WMF file in the object
+The method loads a WMF file in the object.
+The method returns `true` if the file has been correctly loaded, or `false` if it has not. 
 
 ```php
 <?php
@@ -87,8 +125,21 @@ The method load a WMF file in the object
 use PhpOffice\WMF\Reader\WMF\Magic;
 
 $reader = new Magic();
+$reader->load('sample.wmf');
+```
 
-$wmf = $reader->load('sample.wmf');
+### `loadFromString`
+
+The method loads a WMF file in the object from a string.
+The method returns `true` if the file has been correctly loaded, or `false` if it has not. 
+
+```php
+<?php
+
+use PhpOffice\WMF\Reader\WMF\Magic;
+
+$reader = new Magic();
+$reader->loadFromString(file_get_contents('sample.wmf'));
 ```
 
 ### `save`
@@ -101,7 +152,6 @@ The method transforms the loaded WMF file in an another image.
 use PhpOffice\WMF\Reader\WMF\Magic;
 
 $reader = new Magic();
-
-$wmf = $reader->load('sample.wmf');
-$wmf->save('sample.png', 'png');
+$reader->load('sample.wmf');
+$reader->save('sample.png', 'png');
 ```
diff --git a/mkdocs.yml b/mkdocs.yml
index 6cec629..d9b8d8c 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -43,7 +43,8 @@ nav:
     - WMF: 'usage/wmf.md'
   - Credits: 'credits.md'
   - Releases:
-      - '0.1.1 (WIP)': 'changes/0.1.1.md'
+      - '0.1.2 (WIP)': 'changes/0.1.2.md'
+      - '0.1.1': 'changes/0.1.1.md'
       - '0.1.0': 'changes/0.1.0.md'
   - Developers:
     - 'Coveralls': 'https://coveralls.io/github/PHPOffice/WMF'
diff --git a/src/WMF/Reader/WMF/GD.php b/src/WMF/Reader/WMF/GD.php
index 197eda0..18ccf88 100644
--- a/src/WMF/Reader/WMF/GD.php
+++ b/src/WMF/Reader/WMF/GD.php
@@ -65,9 +65,9 @@ public function __destruct()
         }
     }
 
-    public function isWMF(string $filename): bool
+    public function isWMF(): bool
     {
-        list(, $key) = unpack('L', substr(file_get_contents($filename), 0, 4));
+        list(, $key) = unpack('L', substr($this->content, 0, 4));
 
         return $key == (int) 0x9AC6CDD7;
     }
@@ -91,6 +91,10 @@ public function loadFromString(string $content): bool
      */
     private function loadContent(): bool
     {
+        if (!$this->isWMF()) {
+            return false;
+        }
+
         $this->pos = 0;
         $this->gdiObjects = [];
         $k = 72 / 25.4;
diff --git a/src/WMF/Reader/WMF/Imagick.php b/src/WMF/Reader/WMF/Imagick.php
index 0fdc113..8aa7e12 100644
--- a/src/WMF/Reader/WMF/Imagick.php
+++ b/src/WMF/Reader/WMF/Imagick.php
@@ -42,12 +42,9 @@ private function loadContent(string $content, bool $isBlob): bool
         }
     }
 
-    public function isWMF(string $filename): bool
+    public function isWMF(): bool
     {
-        $im = new ImagickBase();
-        $im->readImage($filename);
-
-        return $im->getImageFormat() === 'WMF';
+        return $this->im->getImageFormat() === 'WMF';
     }
 
     public function getResource(): ImagickBase
diff --git a/src/WMF/Reader/WMF/Magic.php b/src/WMF/Reader/WMF/Magic.php
index 6060b0c..3095891 100644
--- a/src/WMF/Reader/WMF/Magic.php
+++ b/src/WMF/Reader/WMF/Magic.php
@@ -11,45 +11,70 @@
 class Magic extends ReaderAbstract
 {
     /**
-     * @var ReaderInterface
+     * @var array<string>
+     */
+    protected $backends = [
+        ImagickReader::class,
+        GD::class,
+    ];
+
+    /**
+     * @var ?ReaderInterface
      */
     protected $reader;
 
-    public function __construct()
+    protected function getBackend(): ?ReaderInterface
     {
-        $reader = null;
-        if (extension_loaded('imagick') && in_array('WMF', ImagickBase::queryformats())) {
-            $reader = new ImagickReader();
+        if ($this->reader) {
+            return $this->reader;
         }
-        if (!$reader && extension_loaded('gd')) {
-            $reader = new GD();
+
+        $reader = null;
+        foreach ($this->backends as $backend) {
+            if ($backend === GD::class) {
+                if (extension_loaded('gd')) {
+                    $reader = new GD();
+
+                    break;
+                }
+            }
+            if ($backend === ImagickReader::class) {
+                if (extension_loaded('imagick') && in_array('WMF', ImagickBase::queryformats())) {
+                    $reader = new ImagickReader();
+                }
+
+                break;
+            }
         }
+
         $this->reader = $reader;
+
+        return $this->reader;
     }
 
     public function load(string $filename): bool
     {
-        return $this->reader->load($filename);
+        return $this->getBackend()->load($filename);
     }
 
     public function loadFromString(string $content): bool
     {
-        return $this->reader->loadFromString($content);
+        return $this->getBackend()->loadFromString($content);
     }
 
     public function save(string $filename, string $format): bool
     {
-        return $this->reader->save($filename, $format);
+        return $this->getBackend()->save($filename, $format);
     }
 
     public function getMediaType(): string
     {
-        return $this->reader->getMediaType();
+        return $this->getBackend()->getMediaType();
     }
 
-    public function isWMF(string $filename): bool
+    public function isWMF(): bool
     {
-        return $this->reader->isWMF($filename);
+        return $this->getBackend()->isWMF();
     }
 
     /**
@@ -59,6 +84,29 @@ public function isWMF(string $filename): bool
      */
     public function getResource()
     {
-        return $this->reader->getResource();
+        return $this->getBackend()->getResource();
+    }
+
+    /**
+     * @return array<string>
+     */
+    public function getBackends(): array
+    {
+        return $this->backends;
+    }
+
+    /**
+     * @param array<string> $backends
+     */
+    public function setBackends(array $backends): self
+    {
+        $this->backends = [];
+        foreach ($backends as $backend) {
+            if (is_a($backend, ReaderInterface::class, true)) {
+                $this->backends[] = $backend;
+            }
+        }
+
+        return $this;
     }
 }
diff --git a/src/WMF/Reader/WMF/ReaderInterface.php b/src/WMF/Reader/WMF/ReaderInterface.php
index 84ace5f..d0a1819 100644
--- a/src/WMF/Reader/WMF/ReaderInterface.php
+++ b/src/WMF/Reader/WMF/ReaderInterface.php
@@ -6,5 +6,5 @@
 
 interface ReaderInterface extends ReaderInterfaceBase
 {
-    public function isWMF(string $filename): bool;
+    public function isWMF(): bool;
 }
diff --git a/tests/WMF/Reader/AbstractTestReader.php b/tests/WMF/Reader/AbstractTestReader.php
index 09cf0d6..1575ac6 100644
--- a/tests/WMF/Reader/AbstractTestReader.php
+++ b/tests/WMF/Reader/AbstractTestReader.php
@@ -55,4 +55,43 @@ public static function dataProviderFilesWMFNotImplemented(): array
             ],
         ];
     }
+
+    /**
+     * @return array<array<string>>
+     */
+    public static function dataProviderMediaType(): array
+    {
+        return [
+            [
+                'gif',
+                'image/gif',
+            ],
+            [
+                'jpg',
+                'image/jpeg',
+            ],
+            [
+                'jpeg',
+                'image/jpeg',
+            ],
+            [
+                'png',
+                'image/png',
+            ],
+            [
+                'webp',
+                'image/webp',
+            ],
+            [
+                'wbmp',
+                'image/vnd.wap.wbmp',
+            ],
+        ];
+    }
+
+    public function assertMimeType(string $filename, string $expectedMimeType): void
+    {
+        $gdInfo = getimagesize($filename);
+        $this->assertEquals($expectedMimeType, $gdInfo['mime']);
+    }
 }
diff --git a/tests/WMF/Reader/WMF/GDTest.php b/tests/WMF/Reader/WMF/GDTest.php
index ec44952..b70e83e 100644
--- a/tests/WMF/Reader/WMF/GDTest.php
+++ b/tests/WMF/Reader/WMF/GDTest.php
@@ -61,6 +61,21 @@ public function testOutput(string $file): void
         @unlink($outputFile);
     }
 
+    /**
+     * @dataProvider dataProviderMediaType
+     */
+    public function testSave(string $extension, string $mediatype): void
+    {
+        $outputFile = $this->getResourceDir() . 'output_save.' . $extension;
+
+        $reader = new GD();
+        $reader->load($this->getResourceDir() . 'burger.wmf');
+        $reader->save($outputFile, $extension);
+        $this->assertMimeType($outputFile, $mediatype);
+
+        @unlink($outputFile);
+    }
+
     public function testSaveWithException(): void
     {
         $file = 'vegetable.wmf';
@@ -90,7 +105,14 @@ public function testSaveWithoutException(): void
     public function testIsWMF(string $file): void
     {
         $reader = new GD();
-        $this->assertTrue($reader->isWMF($this->getResourceDir() . $file));
+        $reader->load($this->getResourceDir() . $file);
+        $this->assertTrue($reader->isWMF());
+    }
+
+    public function testMediaType(): void
+    {
+        $reader = new GD();
+        $this->assertEquals('image/wmf', $reader->getMediaType());
     }
 
     /**
diff --git a/tests/WMF/Reader/WMF/ImagickTest.php b/tests/WMF/Reader/WMF/ImagickTest.php
index 1bbdd40..96a9845 100644
--- a/tests/WMF/Reader/WMF/ImagickTest.php
+++ b/tests/WMF/Reader/WMF/ImagickTest.php
@@ -56,6 +56,21 @@ public function testOutput(string $file): void
         @unlink($outputFile);
     }
 
+    /**
+     * @dataProvider dataProviderMediaType
+     */
+    public function testSave(string $extension, string $mediatype): void
+    {
+        $outputFile = $this->getResourceDir() . 'output_save.' . $extension;
+
+        $reader = new ImagickReader();
+        $reader->load($this->getResourceDir() . 'burger.wmf');
+        $reader->save($outputFile, $extension);
+        $this->assertMimeType($outputFile, $mediatype);
+
+        @unlink($outputFile);
+    }
+
     public function testSaveWithException(): void
     {
         $file = 'vegetable.wmf';
@@ -85,7 +100,14 @@ public function testSaveWithoutException(): void
     public function testIsWMF(string $file): void
     {
         $reader = new ImagickReader();
-        $this->assertTrue($reader->isWMF($this->getResourceDir() . $file));
+        $reader->load($this->getResourceDir() . $file);
+        $this->assertTrue($reader->isWMF());
+    }
+
+    public function testMediaType(): void
+    {
+        $reader = new ImagickReader();
+        $this->assertEquals('image/wmf', $reader->getMediaType());
     }
 
     /**
diff --git a/tests/WMF/Reader/WMF/MagicGDTest.php b/tests/WMF/Reader/WMF/MagicGDTest.php
new file mode 100644
index 0000000..a613616
--- /dev/null
+++ b/tests/WMF/Reader/WMF/MagicGDTest.php
@@ -0,0 +1,107 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\PhpOffice\WMF\Reader\WMF;
+
+use GdImage;
+use PhpOffice\WMF\Reader\WMF\GD;
+use PhpOffice\WMF\Reader\WMF\Imagick;
+use PhpOffice\WMF\Reader\WMF\Magic;
+use PhpOffice\WMF\Reader\WMF\ReaderInterface;
+use Tests\PhpOffice\WMF\Reader\AbstractTestReader;
+
+class MagicGDTest extends AbstractTestReader
+{
+    private function getReader(): ReaderInterface
+    {
+        $reader = new Magic();
+        $reader->setBackends([
+            GD::class,
+            Imagick::class,
+        ]);
+
+        return $reader;
+    }
+
+    /**
+     * @dataProvider dataProviderFilesWMF
+     */
+    public function testLoad(string $file): void
+    {
+        $reader = $this->getReader();
+        $this->assertTrue($reader->load($this->getResourceDir() . $file));
+    }
+
+    /**
+     * @dataProvider dataProviderFilesWMF
+     */
+    public function testLoadFromString(string $file): void
+    {
+        $reader = $this->getReader();
+        $this->assertTrue($reader->loadFromString(file_get_contents($this->getResourceDir() . $file)));
+    }
+
+    /**
+     * @dataProvider dataProviderFilesWMF
+     */
+    public function testGetResource(string $file): void
+    {
+        $reader = $this->getReader();
+        $reader->load($this->getResourceDir() . $file);
+        if (\PHP_VERSION_ID < 80000) {
+            $this->assertIsResource($reader->getResource());
+        } else {
+            /* @phpstan-ignore-next-line */
+            $this->assertInstanceOf(GdImage::class, $reader->getResource());
+        }
+    }
+
+    /**
+     * @dataProvider dataProviderFilesWMF
+     */
+    public function testOutput(string $file): void
+    {
+        $outputFile = $this->getResourceDir() . 'output_' . pathinfo($file, PATHINFO_FILENAME) . '.png';
+        $similarFile = $this->getResourceDir() . pathinfo($file, PATHINFO_FILENAME) . '.png';
+
+        $reader = $this->getReader();
+        $reader->load($this->getResourceDir() . $file);
+        $reader->save($outputFile, 'png');
+
+        $this->assertImageCompare($outputFile, $similarFile, 0.02);
+
+        @unlink($outputFile);
+    }
+
+    /**
+     * @dataProvider dataProviderMediaType
+     */
+    public function testSave(string $extension, string $mediatype): void
+    {
+        $outputFile = $this->getResourceDir() . 'output_save.' . $extension;
+
+        $reader = $this->getReader();
+        $reader->load($this->getResourceDir() . 'burger.wmf');
+        $reader->save($outputFile, $extension);
+        $this->assertMimeType($outputFile, $mediatype);
+
+        @unlink($outputFile);
+    }
+
+    /**
+     * @dataProvider dataProviderFilesWMF
+     */
+    public function testIsWMF(string $file): void
+    {
+        $reader = $this->getReader();
+        $reader->load($this->getResourceDir() . $file);
+        $this->assertTrue($reader->isWMF());
+    }
+
+    public function testMediaType(): void
+    {
+        $reader = $this->getReader();
+        $this->assertEquals('image/wmf', $reader->getMediaType());
+    }
+}
diff --git a/tests/WMF/Reader/WMF/MagicImagickTest.php b/tests/WMF/Reader/WMF/MagicImagickTest.php
new file mode 100644
index 0000000..7fa57f5
--- /dev/null
+++ b/tests/WMF/Reader/WMF/MagicImagickTest.php
@@ -0,0 +1,101 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\PhpOffice\WMF\Reader\WMF;
+
+use PhpOffice\WMF\Reader\WMF\GD;
+use PhpOffice\WMF\Reader\WMF\Imagick;
+use PhpOffice\WMF\Reader\WMF\Magic;
+use PhpOffice\WMF\Reader\WMF\ReaderInterface;
+use Tests\PhpOffice\WMF\Reader\AbstractTestReader;
+
+class MagicImagickTest extends AbstractTestReader
+{
+    private function getReader(): ReaderInterface
+    {
+        $reader = new Magic();
+        $reader->setBackends([
+            Imagick::class,
+            GD::class,
+        ]);
+
+        return $reader;
+    }
+
+    /**
+     * @dataProvider dataProviderFilesWMF
+     */
+    public function testLoad(string $file): void
+    {
+        $reader = $this->getReader();
+        $this->assertTrue($reader->load($this->getResourceDir() . $file));
+    }
+
+    /**
+     * @dataProvider dataProviderFilesWMF
+     */
+    public function testLoadFromString(string $file): void
+    {
+        $reader = $this->getReader();
+        $this->assertTrue($reader->loadFromString(file_get_contents($this->getResourceDir() . $file)));
+    }
+
+    /**
+     * @dataProvider dataProviderFilesWMF
+     */
+    public function testGetResource(string $file): void
+    {
+        $reader = $this->getReader();
+        $reader->load($this->getResourceDir() . $file);
+        $this->assertIsObject($reader->getResource());
+    }
+
+    /**
+     * @dataProvider dataProviderFilesWMF
+     */
+    public function testOutput(string $file): void
+    {
+        $outputFile = $this->getResourceDir() . 'output_' . pathinfo($file, PATHINFO_FILENAME) . '.png';
+        $similarFile = $this->getResourceDir() . pathinfo($file, PATHINFO_FILENAME) . '.png';
+
+        $reader = $this->getReader();
+        $reader->load($this->getResourceDir() . $file);
+        $reader->save($outputFile, 'png');
+
+        $this->assertImageCompare($outputFile, $similarFile, 0.02);
+
+        @unlink($outputFile);
+    }
+
+    /**
+     * @dataProvider dataProviderMediaType
+     */
+    public function testSave(string $extension, string $mediatype): void
+    {
+        $outputFile = $this->getResourceDir() . 'output_save.' . $extension;
+
+        $reader = $this->getReader();
+        $reader->load($this->getResourceDir() . 'burger.wmf');
+        $reader->save($outputFile, $extension);
+        $this->assertMimeType($outputFile, $mediatype);
+
+        @unlink($outputFile);
+    }
+
+    /**
+     * @dataProvider dataProviderFilesWMF
+     */
+    public function testIsWMF(string $file): void
+    {
+        $reader = $this->getReader();
+        $reader->load($this->getResourceDir() . $file);
+        $this->assertTrue($reader->isWMF());
+    }
+
+    public function testMediaType(): void
+    {
+        $reader = $this->getReader();
+        $this->assertEquals('image/wmf', $reader->getMediaType());
+    }
+}
diff --git a/tests/WMF/Reader/WMF/MagicTest.php b/tests/WMF/Reader/WMF/MagicTest.php
index 1c6bdb4..14cd7af 100644
--- a/tests/WMF/Reader/WMF/MagicTest.php
+++ b/tests/WMF/Reader/WMF/MagicTest.php
@@ -4,62 +4,32 @@
 
 namespace Tests\PhpOffice\WMF\Reader\WMF;
 
+use PhpOffice\WMF\Reader\WMF\GD;
+use PhpOffice\WMF\Reader\WMF\Imagick;
 use PhpOffice\WMF\Reader\WMF\Magic;
 use Tests\PhpOffice\WMF\Reader\AbstractTestReader;
 
 class MagicTest extends AbstractTestReader
 {
-    /**
-     * @dataProvider dataProviderFilesWMF
-     */
-    public function testLoad(string $file): void
+    public function testGetBackends(): void
     {
         $reader = new Magic();
-        $this->assertTrue($reader->load($this->getResourceDir() . $file));
+        $this->assertEquals([
+            Imagick::class,
+            GD::class,
+        ], $reader->getBackends());
     }
 
-    /**
-     * @dataProvider dataProviderFilesWMF
-     */
-    public function testLoadFromString(string $file): void
+    public function testSetBackends(): void
     {
         $reader = new Magic();
-        $this->assertTrue($reader->loadFromString(file_get_contents($this->getResourceDir() . $file)));
-    }
-
-    /**
-     * @dataProvider dataProviderFilesWMF
-     */
-    public function testGetResource(string $file): void
-    {
-        $reader = new Magic();
-        $reader->load($this->getResourceDir() . $file);
-        $this->assertIsObject($reader->getResource());
-    }
-
-    /**
-     * @dataProvider dataProviderFilesWMF
-     */
-    public function testOutput(string $file): void
-    {
-        $outputFile = $this->getResourceDir() . 'output_' . pathinfo($file, PATHINFO_FILENAME) . '.png';
-        $similarFile = $this->getResourceDir() . pathinfo($file, PATHINFO_FILENAME) . '.png';
-
-        $reader = new Magic();
-        $reader->load($this->getResourceDir() . $file);
-        $reader->save($outputFile, 'png');
-
-        $this->assertImageCompare($outputFile, $similarFile, 0.02);
-
-        @unlink($outputFile);
-    }
-
-    /**
-     * @dataProvider dataProviderFilesWMF
-     */
-    public function testIsWMF(string $file): void
-    {
-        $reader = new Magic();
-        $this->assertTrue($reader->isWMF($this->getResourceDir() . $file));
+        $this->assertInstanceOf(Magic::class, $reader->setBackends([
+            GD::class,
+            Imagick::class,
+        ]));
+        $this->assertEquals([
+            GD::class,
+            Imagick::class,
+        ], $reader->getBackends());
     }
 }