[ronald-urbina]

Problem

Chromecast playback stalls silently for HLS streams that have separate audio
renditions using raw ADTS AAC segments (.aac). The LOAD request sent to the
receiver had hlsSegmentFormat: "ts" because format detection only inspected
the video variant playlist then applied that format to the audio field too.

The receiver interprets hlsSegmentFormat as the audio segment format. Telling
it "audio is MPEG-TS" when it receives raw .aac files causes it to hang
indefinitely with no error.

Fixes 224.

Changes

castable-utils.js

• Add parseAudioRenditionUrl() — finds the first #EXT-X-MEDIA TYPE=AUDIO
  URI in the master playlist
• getPlaylistSegmentFormat() now separately detects video and audio formats,
  fetching the audio rendition playlist when present
• Returns { videoFormat, audioFormat } instead of a single string
• Fix parseSegment() to trim the returned line (handles CRLF line endings)

castable-mixin.js

• Set hlsSegmentFormat from audioFormat, hlsVideoSegmentFormat from
  videoFormat
• .aac audio → hlsSegmentFormat = AAC, hlsVideoSegmentFormat = MPEG2_TS
• TS video/audio → hlsSegmentFormat = TS, hlsVideoSegmentFormat = MPEG2_TS
  (also fixes the latent bug where HlsVideoSegmentFormat.TS was undefined)
• FMP4 → both remain FMP4

---

Note

Medium Risk
Changes HLS manifest parsing and Chromecast LoadRequest metadata for segment format selection; mistakes could regress casting playback for some HLS variants despite being scoped to HLS-only logic.

Overview
Fixes Chromecast stalls on HLS streams that use separate AAC audio renditions by detecting audio and video segment formats independently.

getPlaylistSegmentFormat() now returns { videoFormat, audioFormat }, trims parsed segment URLs, and (when present) fetches the #EXT-X-MEDIA TYPE=AUDIO playlist to determine audio segment type. The sender LoadRequest mapping is updated to set hlsSegmentFormat from the audio format (including explicit AAC handling) and hlsVideoSegmentFormat from the video format, using MPEG2_TS for TS video.

^{Reviewed by Cursor Bugbot for commit 947ef46. Bugbot is set up for automated code reviews on this repo. Configure here.}

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