LibMagickMediaHandler.php: add support for animated webp thumbnails

inc/Service/Media/LibMagickMediaHandler.php

@@ -8,7 +8,7 @@ use Vichan\Functions\{Fs, Metadata};
 class LibMagickMediaHandler implements MediaHandler {
 	use MediaHandlerTrait;
 
-	// getImageAlphaChannel requires Imagick >= 2.3.0 and ImageMagick >= 6.4.0
+	// getImageAlphaChannel and writeImages requires Imagick >= 2.3.0 and ImageMagick >= 6.4.0
 	private const MIN_IMAGICK_VERSION = '2.3.0';
 	private const MIN_IMAGEMAGICK_VERSION = '6.4.0';
 
@@ -17,10 +17,11 @@ class LibMagickMediaHandler implements MediaHandler {
 
 
 	private bool $strip_metadata;
-	private bool $frames_for_gif_thumbs;
+	private bool $frames_for_animated_thumbs;
 	private int $image_max_width;
 	private int $image_max_height;
 	private string $static_thumb_mime;
+	private ?string $animated_thumb_mime;
 
 
 	private static function degreesFromOrientation(int $orientation): int {
@@ -65,6 +66,13 @@ class LibMagickMediaHandler implements MediaHandler {
 		}
 	}
 
+	/**
+	 * If the mime type supports animations.
+	 */
+	private static function mimeSupportAnimation(string $mime) {
+		return $mime === 'image/gif' || $mime === 'image/webp';
+	}
+
 	/**
 	 * @return bool Returns if width and height were swapped.
 	 */
@@ -83,6 +91,40 @@ class LibMagickMediaHandler implements MediaHandler {
 		}
 	}
 
+	private function generateThumbImplSingleFrame(
+		\Imagick $imagick,
+		string $preferred_out_file_basepath,
+		int $width,
+		int $height,
+		int $max_width,
+		int $max_height
+	) {
+		if ($width > $max_width || $height > $max_height) {
+			$thumb_width = $max_width;
+			$thumb_height = $max_height;
+
+			// Unreliable behavior on some versions if the target width/height are under the limit?
+			$imagick->thumbnailImage($max_width, $max_height, true);
+		} else {
+			$thumb_width = $width;
+			$thumb_height = $height;
+		}
+
+		$out_ext = Metadata\mime_to_ext($this->static_thumb_mime);
+		$out_path = "$preferred_out_file_basepath.$out_ext";
+
+		$imagick->stripImage();
+		$imagick->setImageCompressionQuality(70);
+		$imagick->writeImage("$out_ext:$out_path");
+
+		return new ThumbGenerationResult(
+			$out_path,
+			$this->static_thumb_mime,
+			$thumb_width,
+			$thumb_height
+		);
+	}
+
 	private function generateThumbImpl(
 		\Imagick $imagick,
 		string $source_file_mime,
@@ -92,13 +134,12 @@ class LibMagickMediaHandler implements MediaHandler {
 		int $max_width,
 		int $max_height
 	) {
-		// Special handling for gifs with multiple frames.
+		$source_is_animated = self::mimeSupportAnimation($source_file_mime) && $imagick->getNumberImages() > 1;
-		if (
+
-			$source_file_mime === 'image/gif'
+		// Special handling for animated images with multiple frames.
-			&& $this->frames_for_gif_thumbs !== self::THUMB_KEEP_FRAMES_NO
+		if ($this->frames_for_animated_thumbs !== self::THUMB_KEEP_FRAMES_NO && $source_is_animated) {
-			&& $imagick->getNumberImages() > 1
+			$animated_thumb_ext = Metadata\mime_to_ext($this->animated_thumb_mime);
-		) {
+			$out_path = "$preferred_out_file_basepath.$animated_thumb_ext";
-			$out_path = $preferred_out_file_basepath . '.gif';
 
 			if ($width > $max_width || $height > $max_height) {
 				$thumb_width = $max_width;
@@ -109,14 +150,15 @@ class LibMagickMediaHandler implements MediaHandler {
 			}
 
 			// By now $this->frames_for_gif_thumbs !== 0.
-			$step = \floor($imagick->getNumberImages() / $this->frames_for_gif_thumbs);
+			$step = \floor($imagick->getNumberImages() / $this->frames_for_animated_thumbs);
 
-			if ($this->frames_for_gif_thumbs !== self::THUMB_KEEP_FRAMES_ALL && $step > 1) {
+			if ($this->frames_for_animated_thumbs !== self::THUMB_KEEP_FRAMES_ALL) {
+				if ($step > 1) {
 					// Reduce the number of frames.
 
 					$other = new \Imagick();
 					try {
-					$other->setFormat('gif');
+						$other->setFormat($animated_thumb_ext);
 
 						for ($i = 0, $j = 0; $i < $imagick->getNumberImages(); $i += $step, $j++) {
 							$imagick->setIteratorIndex($i);
@@ -132,49 +174,47 @@ class LibMagickMediaHandler implements MediaHandler {
 						$other->optimizeImageLayers();
 
 						$other->setImageCompressionQuality(70);
-					$other->writeImage("gif:$out_path");
+						$other->writeImages("$animated_thumb_ext:$out_path", true);
 					} finally {
 						$other->clear();
 					}
+				} else {
+					// Only a single frame would be left, save it as a single image.
+					$imagick->setIteratorIndex(0);
+
+					return $this->generateThumbImplSingleFrame(
+						$imagick,
+						$preferred_out_file_basepath,
+						$width,
+						$height,
+						$max_width,
+						$max_height
+					);
+				}
 			} else {
 				// Just try to optimize it a little.
 				$imagick->stripImage();
 				$imagick->optimizeImageLayers();
 
+				$imagick->setFormat($animated_thumb_ext);
 				$imagick->setImageCompressionQuality(70);
-				$imagick->writeImage("gif:$out_path");
+				$imagick->writeImages("$animated_thumb_ext:$out_path", true);
 			}
 
 			return new ThumbGenerationResult(
 				$out_path,
-				'image/gif',
+				$this->animated_thumb_mime,
 				$thumb_width,
 				$thumb_height
 			);
 		} else {
-			if ($width > $max_width || $height > $max_height) {
+			return $this->generateThumbImplSingleFrame(
-				$thumb_width = $max_width;
+				$imagick,
-				$thumb_height = $max_height;
+				$preferred_out_file_basepath,
-
+				$width,
-				// Unreliable behavior on some versions if the target width/height are under the limit?
+				$height,
-				$imagick->thumbnailImage($max_width, $max_height, true);
+				$max_width,
-			} else {
+				$max_height
-				$thumb_width = $width;
-				$thumb_height = $height;
-			}
-
-			$out_ext = Metadata\mime_to_ext($this->static_thumb_mime);
-			$out_path = $preferred_out_file_basepath . '.' . $out_ext;
-
-			$imagick->stripImage();
-			$imagick->setImageCompressionQuality(70);
-			$imagick->writeImage("$out_ext:$out_path");
-
-			return new ThumbGenerationResult(
-				$out_path,
-				$this->static_thumb_mime,
-				$thumb_width,
-				$thumb_height
 			);
 		}
 	}
@@ -184,22 +224,46 @@ class LibMagickMediaHandler implements MediaHandler {
 	 * @return bool
 	 */
 	public static function checkImagickVersion(): bool {
+		static $version_ok = null;
+
+		if ($version_ok === null) {
+			$version_ok = false;
 			$imagick_ver = \phpversion('imagick');
 			if ($imagick_ver !== false && \version_compare($imagick_ver, self::MIN_IMAGICK_VERSION, '>=')) {
 				$str = \Imagick::getVersion()['versionString'];
 				if (\preg_match('/ImageMagick ([0-9]+\.[0-9]+\.[0-9]+)/', $str, $matches)) {
-				return \version_compare($matches[1], self::MIN_IMAGEMAGICK_VERSION, '>=');
+					$version_ok = \version_compare($matches[1], self::MIN_IMAGEMAGICK_VERSION, '>=');
 				}
 			}
-		return false;
 		}
 
-	public function __construct(bool $strip_metadata, int $frames_for_gif_thumbs, int $max_width, int $max_height, string $static_thumb_mime) {
+		return $version_ok;
+	}
+
+	public function __construct(
+		bool $strip_metadata,
+		int $frames_for_animated_thumbs,
+		int $max_width,
+		int $max_height,
+		string $static_thumb_mime,
+		?string $animated_thumb_mime
+	) {
+		if (!self::checkImagickVersion()) {
+			throw new MediaException('Imagick extension or ImageMagick are not available or too old', MediaException::ERR_BAD_HANDLER);
+		}
+		if ($frames_for_animated_thumbs !== self::THUMB_KEEP_FRAMES_NO && $animated_thumb_mime === null) {
+			throw new MediaException('Missing mime type for animated thumbnails', MediaException::ERR_BAD_MEDIA_TYPE);
+		}
+		if ($animated_thumb_mime !== null && !self::mimeSupportAnimation($animated_thumb_mime)) {
+			throw new MediaException("$animated_thumb_mime does not support animations", MediaException::ERR_BAD_MEDIA_TYPE);
+		}
+
 		$this->strip_metadata = $strip_metadata;
-		$this->frames_for_gif_thumbs = $frames_for_gif_thumbs;
+		$this->frames_for_animated_thumbs = $frames_for_animated_thumbs;
 		$this->image_max_width = $max_width;
 		$this->image_max_height = $max_height;
 		$this->static_thumb_mime = $static_thumb_mime;
+		$this->animated_thumb_mime = $animated_thumb_mime;
 	}
 
 	public function supportsMime(string $mime): bool {
@@ -324,7 +388,7 @@ class LibMagickMediaHandler implements MediaHandler {
 			}
 
 			$out_ext = Metadata\mime_to_ext($media_file_mime);
-			$out_path = $media_preferred_out_file_basepath . '.' . $out_ext;
+			$out_path = "$media_preferred_out_file_basepath.$out_ext";
 			$imagick->writeImage("$out_ext:$out_path");
 
 			$thumb = self::generateThumbImpl(