refactor(server): video transcode processor (#2163)

* refactor(server): video transcode processor

* refactor: rename shouldRotate to isVideoVertical, remove unnecessary await

* refactor: rename getOptions to getFfmpegOptions to be clearer in that context

* fix: optimal preset converting vertical videos already smaller than target resolution

---------

Co-authored-by: Zack Pollard <zackpollard@ymail.com>

server/libs/infra/src/repositories/media.repository.ts

@@ -1,7 +1,10 @@
-import { IMediaRepository, ResizeOptions } from '@app/domain';
+import { IMediaRepository, ResizeOptions, VideoInfo } from '@app/domain';
 import { exiftool } from 'exiftool-vendored';
-import ffmpeg from 'fluent-ffmpeg';
+import ffmpeg, { FfprobeData } from 'fluent-ffmpeg';
 import sharp from 'sharp';
+import { promisify } from 'util';
+
+const probe = promisify<string, FfprobeData>(ffmpeg.ffprobe);
 
 export class MediaRepository implements IMediaRepository {
   extractThumbnailFromExif(input: string, output: string): Promise<void> {
@@ -42,4 +45,31 @@ export class MediaRepository implements IMediaRepository {
         .run();
     });
   }
+
+  async probe(input: string): Promise<VideoInfo> {
+    const results = await probe(input);
+
+    return {
+      streams: results.streams.map((stream) => ({
+        height: stream.height || 0,
+        width: stream.width || 0,
+        codecName: stream.codec_name,
+        codecType: stream.codec_type,
+        frameCount: Number.parseInt(stream.nb_frames ?? '0'),
+        rotation: Number.parseInt(`${stream.rotation ?? 0}`),
+      })),
+    };
+  }
+
+  transcode(input: string, output: string, options: string[]): Promise<void> {
+    return new Promise((resolve, reject) => {
+      ffmpeg(input)
+        //
+        .outputOptions(options)
+        .output(output)
+        .on('error', reject)
+        .on('end', resolve)
+        .run();
+    });
+  }
 }