feat(preview): generate previews for JPEG 2000 images

lib/composer/composer/autoload_classmap.php

@@ -2154,6 +2154,7 @@
     'OC\\Preview\\Image' => $baseDir . '/lib/private/Preview/Image.php',
     'OC\\Preview\\Imaginary' => $baseDir . '/lib/private/Preview/Imaginary.php',
     'OC\\Preview\\ImaginaryPDF' => $baseDir . '/lib/private/Preview/ImaginaryPDF.php',
+    'OC\\Preview\\JP2' => $baseDir . '/lib/private/Preview/JP2.php',
     'OC\\Preview\\JPEG' => $baseDir . '/lib/private/Preview/JPEG.php',
     'OC\\Preview\\Krita' => $baseDir . '/lib/private/Preview/Krita.php',
     'OC\\Preview\\MP3' => $baseDir . '/lib/private/Preview/MP3.php',

lib/composer/composer/autoload_static.php

@@ -2195,6 +2195,7 @@ class ComposerStaticInit749170dad3f5e7f9ca158f5a9f04f6a2
         'OC\\Preview\\Image' => __DIR__ . '/../../..' . '/lib/private/Preview/Image.php',
         'OC\\Preview\\Imaginary' => __DIR__ . '/../../..' . '/lib/private/Preview/Imaginary.php',
         'OC\\Preview\\ImaginaryPDF' => __DIR__ . '/../../..' . '/lib/private/Preview/ImaginaryPDF.php',
+        'OC\\Preview\\JP2' => __DIR__ . '/../../..' . '/lib/private/Preview/JP2.php',
         'OC\\Preview\\JPEG' => __DIR__ . '/../../..' . '/lib/private/Preview/JPEG.php',
         'OC\\Preview\\Krita' => __DIR__ . '/../../..' . '/lib/private/Preview/Krita.php',
         'OC\\Preview\\MP3' => __DIR__ . '/../../..' . '/lib/private/Preview/MP3.php',

lib/private/Preview/JP2.php

@@ -0,0 +1,38 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+namespace OC\Preview;
+
+//.jp2
+class JP2 extends Bitmap {
+	#[\Override]
+	public function getMimeType(): string {
+		return '/image\/jp2/';
+	}
+
+	#[\Override]
+	protected function getAllowedMimeTypes(): string {
+		return '/image\/jp2/';
+	}
+
+	#[\Override]
+	protected function getMagicStrings(): array {
+		return [
+			// The JP2 signature box, which opens the file: its length, the
+			// box type, and the four bytes that catch a transfer having
+			// mangled the line endings
+			"\x00\x00\x00\x0CjP  \x0D\x0A\x87\x0A",
+		];
+	}
+
+	#[\Override]
+	protected function getImagickFormatHint(): string {
+		return 'jp2';
+	}
+}

lib/private/PreviewManager.php

@@ -25,6 +25,7 @@
 use OC\Preview\IMagickSupport;
 use OC\Preview\Imaginary;
 use OC\Preview\ImaginaryPDF;
+use OC\Preview\JP2;
 use OC\Preview\JPEG;
 use OC\Preview\Krita;
 use OC\Preview\MarkDown;
@@ -332,6 +333,7 @@ protected function registerCoreProviders(): void {
 			$imagickProviders = [
 				'SVG' => ['mimetype' => '/image\/svg\+xml/', 'class' => SVG::class],
 				'TIFF' => ['mimetype' => '/image\/tiff/', 'class' => TIFF::class],
+				'JP2' => ['mimetype' => '/image\/jp2/', 'class' => JP2::class],
 				'PDF' => ['mimetype' => '/application\/pdf/', 'class' => PDF::class],
 				'AI' => ['mimetype' => '/application\/illustrator/', 'class' => Illustrator::class],
 				'PSD' => ['mimetype' => '/application\/x-photoshop/', 'class' => Photoshop::class],

tests/data/REUSE.toml

@@ -34,7 +34,7 @@ SPDX-FileCopyrightText = "2012 ownCloud, Inc."
 SPDX-License-Identifier = "AGPL-3.0-only"
 
 [[annotations]]
-path = ["testavatar.png", "testimage.avif", "testimage.gif", "testimage.jpg", "testimage.png"]
+path = ["testavatar.png", "testimage.avif", "testimage.gif", "testimage.jp2", "testimage.jpg", "testimage.png"]
 precedence = "aggregate"
 SPDX-FileCopyrightText = "2013 ownCloud, Inc."
 SPDX-License-Identifier = "AGPL-3.0-only"

tests/lib/Preview/AVIFImagickTest.php

@@ -16,7 +16,7 @@
  */
 #[\PHPUnit\Framework\Attributes\Group('DB')]
 class AVIFImagickTest extends Provider {
-	use AvifPreviewTrait;
+	use PreviewPixelsTrait;
 
 	#[\Override]
 	protected function setUp(): void {

tests/lib/Preview/AVIFTest.php

@@ -17,7 +17,7 @@
  */
 #[\PHPUnit\Framework\Attributes\Group('DB')]
 class AVIFTest extends Provider {
-	use AvifPreviewTrait;
+	use PreviewPixelsTrait;
 
 	#[\Override]
 	protected function setUp(): void {

tests/lib/Preview/JP2Test.php

@@ -0,0 +1,54 @@
+<?php
+
+/**
+ * SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace Test\Preview;
+
+use OC\Preview\JP2;
+
+/**
+ * Class JP2Test
+ *
+ * @package Test\Preview
+ */
+#[\PHPUnit\Framework\Attributes\Group('DB')]
+class JP2Test extends Provider {
+	use PreviewPixelsTrait;
+
+	#[\Override]
+	protected function setUp(): void {
+		if (!extension_loaded('imagick')) {
+			$this->markTestSkipped('ImageMagick is not installed. Skipping tests');
+		}
+		if (!in_array('JP2', \Imagick::queryFormats('JP2'), true)) {
+			$this->markTestSkipped('ImageMagick was built without JPEG 2000. Skipping tests');
+		}
+
+		$fileName = 'testimage.jp2';
+		$sourcePath = \OC::$SERVERROOT . '/tests/data/' . $fileName;
+
+		// Reporting the coder is not the same as being able to use it: the
+		// OpenJPEG delegate may be missing, or policy.xml may have disabled
+		// it, in which case decoding throws and the tests would fail rather
+		// than skip. Decode once for real before committing to them.
+		try {
+			(new \Imagick())->readImage('jp2:' . $sourcePath . '[0]');
+		} catch (\ImagickException $e) {
+			$this->markTestSkipped('ImageMagick cannot decode JPEG 2000 here: ' . $e->getMessage() . '. Skipping tests');
+		}
+
+		parent::setUp();
+
+		$this->imgPath = $this->prepareTestFile($fileName, $sourcePath);
+		$this->width = 1680;
+		$this->height = 1050;
+		$this->provider = new JP2();
+	}
+
+	public function testPreviewCarriesThePicture(): void {
+		$this->assertPreviewShowsThePicture();
+	}
+}

tests/lib/Preview/AvifPreviewTrait.php → tests/lib/Preview/PreviewPixelsTrait.php

@@ -18,7 +18,7 @@
  * came back, which a blank canvas of the right shape would satisfy just as
  * well as a decoded photo. These read the pixels.
  */
-trait AvifPreviewTrait {
+trait PreviewPixelsTrait {
 	/** How far the average may drift, over encoding and scaling */
 	private int $tolerance = 12;
 
@@ -66,9 +66,9 @@ protected function assertPreviewShowsThePicture(): void {
 		$this->assertLessThanOrEqual(256, $preview->width());
 		$this->assertLessThanOrEqual(256, $preview->height());
 
-		// The fixture is a re-encode of testimage.jpg, so the two hold the
-		// same picture: a strong magenta whose average survives both the
-		// encoding and the scaling. A blank or black canvas misses by ~250.
+		// Every fixture using this is a re-encode of testimage.jpg, so they
+		// hold the same picture: a strong magenta whose average survives
+		// the encoding and the scaling. A blank canvas misses by ~250.
 		$expected = $this->meanColour(file_get_contents(\OC::$SERVERROOT . '/tests/data/testimage.jpg'));
 		$actual = $this->meanColour($preview->data());