Add ffprobe module

packages/transcode/analyze.test.ts

@@ -1,11 +1,11 @@
 import { assertEquals } from '@std/assert';
 
-import { ffmpegDim } from './analyze.ts';
+import { getVideoDimensions } from './analyze.ts';
 
-Deno.test('ffmpegDim', async () => {
-  await using file = await Deno.open(new URL('./buckbunny.mp4', import.meta.url));
+Deno.test('getVideoDimensions', async () => {
+  const uri = new URL('./buckbunny.mp4', import.meta.url);
 
-  const result = await ffmpegDim(file.readable);
+  const dimensions = await getVideoDimensions(uri.href);
 
-  assertEquals(result, { width: 1280, height: 720 });
+  assertEquals(dimensions, { width: 1920, height: 1080 });
 });

packages/transcode/analyze.ts

@@ -1,17 +1,13 @@
-import { ffmpeg } from './ffmpeg.ts';
+import { ffprobe } from './ffprobe.ts';
 
-export async function ffmpegDim(
-  input: ReadableStream<Uint8Array>,
-): Promise<{ width: number; height: number } | undefined> {
-  const result = ffmpeg(input, {
-    'vf': 'showinfo', // Output as JSON
-    'f': 'null', // Tell FFmpeg not to produce an output file
+export async function getVideoDimensions(path: string): Promise<{ width: number; height: number } | null> {
+  const stream = ffprobe(path, {
+    'v': 'error',
+    'select_streams': 'v:0',
+    'show_entries': 'stream=width,height',
+    'of': 'json',
   });
 
-  const text = await new Response(result).json();
-  console.log(text);
-  const output = JSON.parse(text);
-
-  const [stream] = output.streams ?? [];
-  return stream;
+  const { streams: [result] } = await new Response(stream).json();
+  return result ?? null;
 }

packages/transcode/ffprobe.test.ts

@@ -0,0 +1,18 @@
+import { assertEquals } from '@std/assert';
+
+import { ffprobe } from './ffprobe.ts';
+
+Deno.test('ffprobe', async () => {
+  const uri = new URL('./buckbunny.mp4', import.meta.url);
+
+  const stream = ffprobe(uri, {
+    'v': 'error',
+    'select_streams': 'v:0',
+    'show_entries': 'stream=width,height',
+    'of': 'json',
+  });
+
+  const { streams: [dimensions] } = await new Response(stream).json();
+
+  assertEquals(dimensions, { width: 1920, height: 1080 });
+});

packages/transcode/ffprobe.ts

@@ -0,0 +1,24 @@
+export interface FFprobeFlags {
+  'v'?: string;
+  'select_streams'?: string;
+  'show_entries'?: string;
+  'of'?: string;
+  [key: string]: string | undefined;
+}
+
+export function ffprobe(path: URL | string, flags: FFprobeFlags): ReadableStream<Uint8Array> {
+  const args = [];
+
+  for (const [key, value] of Object.entries(flags)) {
+    if (typeof value === 'string') {
+      args.push(`-${key}`, value);
+    }
+  }
+
+  args.push(path instanceof URL ? path.href : path);
+
+  const command = new Deno.Command('ffprobe', { args, stdout: 'piped' });
+  const child = command.spawn();
+
+  return child.stdout;
+}