fix(subtitles): retain uncertain audio during dialogue generation

- Preserve audio rejected by VAD so dialogue under music is retained. - Keep short passages intact and stitch overlapping cues despite punctuation differences.
2026-09-17 05:16:19 -07:00 · 2026-09-14 19:16:34 -07:00
parent d6cbacf8be
commit 02792232c2
15 changed files with 242 additions and 19 deletions
@@ -0,0 +1,73 @@
+import assert from 'node:assert/strict';
+import { mkdtemp, rm, writeFile } from 'node:fs/promises';
+import { tmpdir } from 'node:os';
+import path from 'node:path';
+import test from 'node:test';
+import { findAudiblePassages, mergeSpeechPassages } from './subtitle-generation-coverage';
+
+async function analyze(lines: string[], progress = 'out_time_us=20000000\n') {
+  const directory = await mkdtemp(path.join(tmpdir(), 'subtitle-coverage-test-'));
+  try {
+    const ffmpegPath = path.join(directory, 'ffmpeg');
+    await writeFile(
+      ffmpegPath,
+      `#!${process.execPath}
+process.stderr.write(${JSON.stringify(lines.join('\n') + '\n')});
+process.stdout.write(${JSON.stringify(progress)});
+`,
+      { mode: 0o755 },
+    );
+    return await findAudiblePassages({ ffmpegPath, wavPath: 'audio.wav' });
+  } finally {
+    await rm(directory, { recursive: true, force: true });
+  }
+}
+
+test('audible coverage retains the full timeline when there is no confident silence', async () => {
+  assert.deepEqual(await analyze([]), [{ startSeconds: 0, endSeconds: 20 }]);
+});
+
+test('audible coverage omits silence while padding nearby audio without exceeding the timeline', async () => {
+  assert.deepEqual(
+    await analyze([
+      '[silencedetect] silence_start: 0',
+      '[silencedetect] silence_end: 2 | silence_duration: 2',
+      '[silencedetect] silence_start: 8',
+      '[silencedetect] silence_end: 12 | silence_duration: 4',
+      '[silencedetect] silence_start: 18',
+    ]),
+    [
+      { startSeconds: 1.65, endSeconds: 8.35 },
+      { startSeconds: 11.65, endSeconds: 18.35 },
+    ],
+  );
+  assert.deepEqual(await analyze(['[silencedetect] silence_end: 10.5 | silence_duration: 0.5']), [
+    { startSeconds: 0, endSeconds: 20 },
+  ]);
+});
+
+test('entirely silent audio has no audible passages', async () => {
+  assert.deepEqual(await analyze(['[silencedetect] silence_start: 0']), []);
+  assert.deepEqual(await analyze(['[silencedetect] silence_end: 20 | silence_duration: 20']), []);
+});
+
+test('missing analysis duration fails instead of silently dropping audio', async () => {
+  await assert.rejects(analyze([], ''), /valid duration/);
+});
+
+test('merging coverage preserves quiet VAD speech and does not mutate detector results', () => {
+  const speech = [{ startSeconds: 10, endSeconds: 11 }];
+  assert.deepEqual(
+    mergeSpeechPassages([
+      ...speech,
+      { startSeconds: 0, endSeconds: 5 },
+      { startSeconds: 4, endSeconds: 8 },
+      { startSeconds: 11, endSeconds: 12 },
+    ]),
+    [
+      { startSeconds: 0, endSeconds: 8 },
+      { startSeconds: 10, endSeconds: 12 },
+    ],
+  );
+  assert.deepEqual(speech, [{ startSeconds: 10, endSeconds: 11 }]);
+});