From 0aa728b1aa24326b82afa2ffd178ade14dbefa82 Mon Sep 17 00:00:00 2001
From: "Abdullah M. Nazif" <abdullahnajif5@gmail.com>
Date: Sat, 24 Oct 2026 04:11:25 +0000
Subject: [PATCH] fix(studio-server): decode authored audio attributes for
 loudness (#5289)

---
 .../src/helpers/loudness.test.ts              | 34 +++++++++++++++++++
 .../studio-server/src/helpers/loudness.ts     | 10 +++++-
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/packages/studio-server/src/helpers/loudness.test.ts b/packages/studio-server/src/helpers/loudness.test.ts
index 898d9093d2..638abb66c6 100644
--- a/packages/studio-server/src/helpers/loudness.test.ts
+++ b/packages/studio-server/src/helpers/loudness.test.ts
@@ -95,6 +95,40 @@ describe("audioTags with video", () => {
   });
 });
 
+describe("audioTags with HTML character references", () => {
+  it.each([
+    { src: "Q&amp;A.wav", expected: "Q&A.wav" },
+    { src: "Q&#38;A.wav", expected: "Q&A.wav" },
+    { src: "Q&#x26;A.wav", expected: "Q&A.wav" },
+    { src: "an&#39;s &quot;reply&quot;.wav", expected: 'an\'s "reply".wav' },
+    { src: "Q&amp;amp;A.wav", expected: "Q&amp;A.wav" },
+  ])("decodes $src once for local file lookup", ({ src, expected }) => {
+    const html = `<audio id="vo" src="${src}"></audio>`;
+    expect(audioTags(html)[0]?.src).toBe(expected);
+  });
+
+  it("patches an entity-encoded id while preserving every other authored byte", () => {
+    const html = `<audio id="voice&#45;over" src="Q&amp;A.wav" data-volume="&#49;"></audio>`;
+    expect(audioTags(html)[0]).toEqual(expect.objectContaining({ id: "voice-over", volume: 1 }));
+    expect(updateAudioVolume(html, "voice-over", 0.5)).toBe(
+      `<audio id="voice&#45;over" src="Q&amp;A.wav" data-volume="0.5"></audio>`,
+    );
+  });
+
+  it("decodes video audibility and timing attributes before interpreting them", () => {
+    const html = `<video id="vo" src="Q&amp;A.mp4" data-has-audio="tr&#117;e" data-media-start="&#50;" data-duration="&#51;" data-playback-rate="&#49;"></video>`;
+    expect(audioTags(html)[0]).toEqual(
+      expect.objectContaining({
+        id: "vo",
+        src: "Q&A.mp4",
+        mediaStart: 2,
+        duration: 3,
+        playbackRate: 1,
+      }),
+    );
+  });
+});
+
 describe("loudnessMeasureArgs with a playback rate", () => {
   it("measures the source span a sped-up clip actually plays", () => {
     const args = loudnessMeasureArgs("clip.mp4", { mediaStart: 0, duration: 4, playbackRate: 2 });
diff --git a/packages/studio-server/src/helpers/loudness.ts b/packages/studio-server/src/helpers/loudness.ts
index 7f13d8ff06..f104894205 100644
--- a/packages/studio-server/src/helpers/loudness.ts
+++ b/packages/studio-server/src/helpers/loudness.ts
@@ -3,6 +3,7 @@ import { isAbsolute, relative, resolve } from "node:path";
 import { promisify } from "node:util";
 import { isAudibleVideoElement } from "@hyperframes/core/audible-video";
 import { formatAudioGain, MAX_AUDIO_GAIN_DB } from "@hyperframes/core/audio-gain";
+import { decodeAuthoredAttribute } from "@hyperframes/parsers";
 import { findFfBinary } from "@hyperframes/parsers/ff-binaries";
 import { readMediaOffsetSeconds } from "@hyperframes/parsers/media-duration";
 import { requestedProjectPath } from "./requestSubPath.js";
@@ -101,7 +102,14 @@ function attributeFromMatch(
   const whole = match[0];
   const localValueStart = attributeValueStart(whole);
   const valueStart = absoluteOffset + match.index + localValueStart;
-  return [name, { value, valueStart, valueEnd: valueStart + value.length }];
+  return [
+    name,
+    {
+      value: decodeAuthoredAttribute(value),
+      valueStart,
+      valueEnd: valueStart + value.length,
+    },
+  ];
 }
 
 function matchedAttributeValue(match: RegExpMatchArray): string | undefined {