なんかもうめっちゃ変えた

packages/backend/src/core/VideoProcessingService.ts

@@ -0,0 +1,44 @@
+import { Inject, Injectable } from '@nestjs/common';
+import FFmpeg from 'fluent-ffmpeg';
+import { DI } from '@/di-symbols.js';
+import { Config } from '@/config.js';
+import { ImageProcessingService } from '@/core/ImageProcessingService.js';
+import type { IImage } from '@/core/ImageProcessingService.js';
+import { createTempDir } from '@/misc/create-temp.js';
+
+@Injectable()
+export class VideoProcessingService {
+	constructor(
+		@Inject(DI.config)
+		private config: Config,
+
+		private imageProcessingService: ImageProcessingService,
+	) {
+	}
+
+	public async generateVideoThumbnail(source: string): Promise<IImage> {
+		const [dir, cleanup] = await createTempDir();
+	
+		try {
+			await new Promise((res, rej) => {
+				FFmpeg({
+					source,
+				})
+					.on('end', res)
+					.on('error', rej)
+					.screenshot({
+						folder: dir,
+						filename: 'out.png',	// must have .png extension
+						count: 1,
+						timestamps: ['5%'],
+					});
+			});
+	
+			// JPEGに変換 (Webpでもいいが、MastodonはWebpをサポートせず表示できなくなる)
+			return await this.imageProcessingService.convertToJpeg(`${dir}/out.png`, 498, 280);
+		} finally {
+			cleanup();
+		}
+	}
+}
+